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New submissions for Thu, 23 Nov 17
 [1] arXiv:1711.07983 [pdf, other]

Title: The close circumstellar environment of Betelgeuse  V. Rotation velocity and molecular envelope properties from ALMAAuthors: Pierre Kervella, Leen Decin, Anita M. S. Richards, Graham M. Harper, Iain McDonald, Eamon O'Gorman, Miguel Montargès, Ward Homan, Keiichi OhnakaComments: 18 pages, 19 figures, accepted for publication in A&ASubjects: Solar and Stellar Astrophysics (astroph.SR)
We observed Betelgeuse using ALMA's extended configuration in band 7 (f~340 GHz, {\lambda}~0.88 mm), resulting in a very high angular resolution of 18 mas. Using a solid body rotation model of the 28SiO(v=2,J=87) line emission, we show that the supergiant is rotating with a projected equatorial velocity of v_eq sin i = 5.47 +/ 0.25 km/s at the equivalent continuum angular radius R_star = 29.50 +/ 0.14 mas. This corresponds to an angular rotation velocity of {\omega} sin i = (5.6 +/ 1.3) x 10^(9) rad/s. The position angle of its north pole is PA = 48.0 +/ 3.5{\deg}. The rotation period of Betelgeuse is estimated to P/sin i = 36 +/ 8 years. The combination of our velocity measurement with previous observations in the ultraviolet shows that the chromosphere is corotating with the star up to a radius of ~10 au (45 mas or 1.5x the ALMA continuum radius). The coincidence of the position angle of the polar axis of Betelgeuse with that of the major ALMA continuum hot spot, a molecular plume, and a partial dust shell (from previous observations) suggests that focused mass loss is currently taking place in the polar region of the star. We propose that this hot spot corresponds to the location of a particularly strong "rogue" convection cell, which emits a focused molecular plume that subsequently condenses into dust at a few stellar radii. Rogue convection cells therefore appear to be an important factor shaping the anisotropic mass loss of red supergiants.
 [2] arXiv:1711.07984 [pdf, other]

Title: Peering beyond the horizon with standard sirens and redshift driftAuthors: Raul Jimenez (1,2), Alvise Raccanelli (1), Licia Verde (1,2), Sabino Matarrese (3,4,5,6) ((1) ICC Barcelona, (2) ICREA, (3) Università di Padova, (4) INFN Padova, (5) INAF Padova, (6) GSSI)Comments: 10 pages, 1 figure, 2 tablesSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
An interesting test on the nature of the Universe is to measure the global spatial curvature of the metric in a model independent way, at a level of $\Omega_k<10^{4}$, or, if possible, at the cosmic variance level of the amplitude of the CMB fluctuations $\Omega_k\approx10^{5}$. A limit of $\Omega_k<10^{4}$ would yield stringent tests on several models of inflation. Further, improving the constraint by an order of magnitude would help in reducing "model confusion" in standard parameter estimation. Moreover, if the curvature is measured to be at the value of the amplitude of the CMB fluctuations, it would offer a powerful test on the inflationary paradigm and would indicate that our Universe must be significantly larger than the current horizon. On the contrary, in the context of standard inflation, measuring a value above CMB fluctuations will lead us to conclude that the Universe is not much larger than the current observed horizon; this can also be interpreted as the presence of large fluctuations outside the horizon. However, it has proven difficult, so far, to find observables that can achieve such level of accuracy, and, most of all, be modelindependent. Here we propose a method that can in principle achieve that; this is done by making minimal assumptions and using distance probes that are cosmologyindependent: gravitational waves, redshift drift and cosmic chronometers. We discuss what kind of observations are needed in principle to achieve the desired accuracy.
 [3] arXiv:1711.07985 [pdf, ps, other]

Title: Declining rotation curves at $z=2$: A natural phenomenon in $Λ$CDM cosmologyAuthors: Adelheid F. Teklu, RheaSilvia Remus, Klaus Dolag, Alexander Arth, Andreas Burkert, Aura Obreja, Felix SchulzeComments: 6 pages, 4 figures, submitted to ApJ Letters, www.magneticum.orgSubjects: Astrophysics of Galaxies (astroph.GA)
Selecting disk galaxies from the cosmological, hydrodynamical simulation Magneticum Pathfinder we show that almost half of our poster child disk galaxies at $z=2$ show significantly declining rotation curves and low dark matter fractions, very similar to recently reported observations. These galaxies do not show any anomalous behavior, reside in standard dark matter halos and typically grow significantly in mass until $z=0$, where they span all morphological classes, including disk galaxies matching present day rotation curves and observed dark matter fractions. Our findings demonstrate that declining rotation curves and low dark matter fractions in rotation dominated galaxies at $z=2$ appear naturally within the $\Lambda$CDM paradigm and reflect the complex baryonic physics, which plays a role at the peak epoch of starformation. In addition, we find that dispersion dominated galaxies at $z=2$, which host a significant gas disk, exhibit similar shaped rotation curves as the disk galaxy population, rendering it difficult to differentiate between these two populations with currently available observation techniques.
 [4] arXiv:1711.07986 [pdf, ps, other]

Title: Revisiting the bulgehalo conspiracy II: Towards explaining its puzzling dependence on redshiftAuthors: Francesco Shankar (1), Alessandro Sonnenfeld (2), Philip Grylls (1), Lorenzo Zanisi (1), Carlo Nipoti (3), KyuHyun Chae (4), Mariangela Bernardi (5), Carlo Enrico Petrillo (6), Marc HuertasCompany (7), Gary A. Mamon (8), Stewart Buchan (1) ((1) University of Southampton, (2) Kavli IPMU, University of Tokyo, (3) Bologna University, (4) Sejong University, (5) University of Pennsylvania, (6) University of Groningen, (7) LERMA, Observatoire de Paris, (8) Institut d'Astrophysique de Paris)Comments: 14 pages, 8 figures. MNRAS, accepted. Main result of the paper in Figure 2Subjects: Astrophysics of Galaxies (astroph.GA); Cosmology and Nongalactic Astrophysics (astroph.CO)
We carry out a systematic investigation of the total mass density profile of massive (Mstar~3e11 Msun) earlytype galaxies and its dependence on redshift, specifically in the range 0<z<1. We start from a large sample of SDSS earlytype galaxies with stellar masses and effective radii measured assuming two different profiles, de Vaucouleurs and S\'{e}rsic. We assign dark matter haloes to galaxies via abundance matching relations with standard LCDM profiles and concentrations. We then compute the total, massweighted density slope at the effective radius gamma', and study its redshift dependence at fixed stellar mass. We find that a necessary condition to induce an increasingly flatter gamma' at higher redshifts, as suggested by current strong lensing data, is to allow the intrinsic stellar profile of massive galaxies to be S\'{e}rsic and the input S\'{e}rsic index n to vary with redshift approximately as n(z)~(1+z)^(1). This conclusion holds irrespective of the input MstarMhalo relation, the assumed stellar initial mass function, or even the chosen level of adiabatic contraction in the model. Secondary contributors to the observed redshift evolution of gamma' may come from an increased contribution at higher redshifts of adiabatic contraction and/or bottomlight stellar initial mass functions. The strong lensing selection effects we have simulated seem not to contribute to this effect. A steadily increasing S\'{e}rsic index with cosmic time is supported by independent observations, though it is not yet clear whether cosmological hierarchical models (e.g., mergers) are capable of reproducing such a fast and sharp evolution.
 [5] arXiv:1711.07987 [pdf, ps, other]

Title: Dynamical equivalence, the origin of the Galactic field stellar and binary population, and the initial radiusmass relation of embedded clustersComments: 6 pages, 2 figures; accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astroph.GA)
In order to allow a better understanding of the origin of Galactic field populations, dynamical equivalence of stellardynamical systems has been postulated by Kroupa and Belloni et al. to allow mapping of solutions of the initial conditions of embedded clusters such that they yield, after a period of dynamical processing, the Galactic field population. Dynamically equivalent systems are defined to initially and finally have the same distribution functions of periods, mass ratios and eccentricities of binary stars. Here we search for dynamically equivalent clusters using the {\sc mocca} code. The simulations confirm that dynamically equivalent solutions indeed exist. The result is that the solution space is next to identical to the radiusmass relation of Marks \& Kroupa, $\left( r_h/{\rm pc} \right)= 0.1^{+0.07}_{0.04}\, \left( M_{\rm ecl}/{\rm M}_\odot \right)^{0.13\pm0.04}$. This relation is in good agreement with the observed density of molecular cloud clumps. According to the solutions, the timescale to reach dynamical equivalence is about 0.5~Myr which is, interestingly, consistent with the lifetime of ultracompact HII regions and the timescale needed for gas expulsion to be active in observed very young clusters as based on their dynamical modelling.
 [6] arXiv:1711.07995 [pdf, other]

Title: CO excitation in the Seyfert galaxy NGC 34: stars, shock or AGN driven?Authors: M. Mingozzi, L. Vallini, F. Pozzi, C. Vignali, A. Mignano, C. Gruppioni, M. Talia, A. Cimatti, G. Cresci, M. MassardiComments: Accepted for publication in MNRAS. 10 pages, 6 figuresSubjects: Astrophysics of Galaxies (astroph.GA)
We present a detailed analysis of the Xray and molecular gas emission in the nearby galaxy NGC 34, to constrain the properties of molecular gas, and assess whether, and to what extent, the radiation produced by the accretion onto the central black hole affects the CO line emission. We analyse the CO Spectral Line Energy Distribution (SLED) as resulting mainly from Herschel and ALMA data, along with Xray data from NuSTAR and XMMNewton. The Xray data analysis suggests the presence of a heavily obscured AGN with an intrinsic luminosity of L$_{\rm{1100\,keV}} \simeq 4.0\times10^{42}$ erg s$^{1}$. ALMA high resolution data ($\theta \simeq 0.2''$) allows us to scan the nuclear region down to a spatial scale of $\approx 100$ pc for the CO(65) transition. We model the observed SLED using PhotoDissociation Region (PDR), XrayDominated Region (XDR), and shock models, finding that a combination of a PDR and an XDR provides the best fit to the observations. The PDR component, characterized by gas density ${\rm log}(n/{\rm cm^{3}})=2.5$ and temperature $T=30$ K, reproduces the lowJ CO line luminosities. The XDR is instead characterised by a denser and warmer gas (${\rm log}(n/{\rm cm^{3}})=4.5$, $T =65$ K), and is necessary to fit the highJ transitions. The addition of a third component to account for the presence of shocks has been also tested but does not improve the fit of the CO SLED. We conclude that the AGN contribution is significant in heating the molecular gas in NGC 34.
 [7] arXiv:1711.08036 [pdf, other]

Title: A Universal Transition in Atmospheric Diffusion for Hot Subdwarfs Near 18,000 KAuthors: T.M. Brown, J.M. Taylor, S. Cassisi, A.V. Sweigart, A. Bellini, L.R. Bedin, M. Salaris, A. Renzini, E. DalessandroComments: Accepted for publication in The Astrophysical Journal. 9 pages, 1 table, 10 figures. Figure 2 is shown at low resolution due to file size limitsSubjects: Solar and Stellar Astrophysics (astroph.SR)
In the colormagnitude diagrams (CMDs) of globular clusters, when the locus of stars on the horizontal branch (HB) extends to hot temperatures, discontinuities are observed at colors corresponding to ~12,000 K and ~18,000 K. The former is the "Grundahl jump" that is associated with the onset of radiative levitation in the atmospheres of hot subdwarfs. The latter is the "Momany jump" that has remained unexplained. Using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, we have obtained ultraviolet and blue spectroscopy of six hot subdwarfs straddling the Momany jump in the massive globular cluster omega Cen. By comparison to model atmospheres and synthetic spectra, we find that the feature is due primarily to a decrease in atmospheric Fe for stars hotter than the feature, amplified by the temperature dependence of the Fe absorption at these effective temperatures.
 [8] arXiv:1711.08044 [pdf, other]

Title: Photonuclear Reactions in Lightning Discovered from Detection of Positrons and NeutronsAuthors: Teruaki Enoto (1), Yuuki Wada (2 and 3), Yoshihiro Furuta (2), Kazuhiro Nakazawa (2), Takayuki Yuasa (4), Kazufumi Okuda (2), Kazuo Makishima (3), Mitsuteru Sato (5), Yousuke Sato (6), Toshio Nakano (3), Daigo Umemoto (3), Harufumi Tsuchiya (7) ((1) Kyoto University, (2) The University of Tokyo, (3) RIKEN, (4) Singapore, (5) Hokkaido University, (6) Nagoya University, (7) JAEA)Comments: This manuscript was submitted to Nature Letter on July 30, 2017, and the original version that has not undergo the peer review process. See the accepted version at Nature website, published on the issue of November 23, 2017 with the revised title "photonuclear reaction triggered by lightning discharge"Journalref: Nature Letter, the issue of November 23, 2017Subjects: High Energy Astrophysical Phenomena (astroph.HE); Atmospheric and Oceanic Physics (physics.aoph)
Lightning and thundercloud are the most dramatic natural particle accelerators on the Earth. Relativistic electrons accelerated by electric fields therein emit bremsstrahlung gamma rays, which have been detected at ground observations, by airborne detectors, and as terrestrial gammaray flashes (TGFs) from space. The energy of the gamma rays is sufficiently high to potentially invoke atmospheric photonuclear reactions 14N(gamma, n)13N, which would produce neutrons and eventually positrons via betaplus decay of generated unstable radioactive isotopes, especially 13N. However, no clear observational evidence for the reaction has been reported to date. Here we report the first detection of neutron and positron signals from lightning with a ground observation. During a thunderstorm on 6 February 2017 in Japan, a TGFlike intense flash (within 1 ms) was detected at our monitoring sites 0.51.7 km away from the lightning. The subsequent initial burst quickly subsided with an exponential decay constant of 4060 ms, followed by a prolonged line emission at about 0.511 megaelectronvolt (MeV), lasting for a minute. The observed decay timescale and spectral cutoff at about 10 MeV of the initial emission are well explained with deexcitation gamma rays from the nuclei excited by neutron capture. The centre energy of the prolonged line emission corresponds to the electronpositron annihilation, and hence is the conclusive indication of positrons produced after the lightning. Our detection of neutrons and positrons is unequivocal evidence that natural lightning triggers photonuclear reactions. No other natural event on the Earth is known to trigger photonuclear reactions. This discovery places lightning as only the second known natural channel on the Earth after the atmospheric cosmicray interaction, in which isotopes, such as 13C, 14C, and 15N, are produced.
 [9] arXiv:1711.08046 [pdf, ps, other]

Title: Tracing the Assembly History of NGC 1395 through its Globular Cluster SystemAuthors: C. G. Escudero, F. R. Faifer, A. V. Smith Castelli, J. C. Forte, L. A. Sesto, N. M. González, M. C. ScaliaComments: 19 pages, 22 figuresSubjects: Astrophysics of Galaxies (astroph.GA)
We used deep GeminiSouth/GMOS g'r'i'z' images to study the globular cluster (GC) system of the massive elliptical galaxy NGC 1395, located in the Eridanus supergroup. The photometric analysis of the GC candidates reveals a clear colour bimodality distribution, indicating the presence of "blue" and "red" GC subpopulations. While a negative radial colour gradient is detected in the projected spatial distribution of the red GCs, the blue GCs display a shallow colour gradient. The blue GCs also display a remarkable shallow and extended surface density profile, suggesting a significant accretion of lowmass satellites in the outer halo of the galaxy. In addition, the slope of the projected spatial distribution of the blue GCs in the outer regions of the galaxy, is similar to that of the Xray halo emission. Integrating up to 165 kpc the profile of the projected spatial distribution of the GCs, we estimated a total GC population and specific frequency of 6000$\pm$1100 and $S_N$=7.4$\pm$1.4, respectively. Regarding NGC 1395 itself, the analysis of the deep Gemini/GMOS images shows a low surface brightness umbrellalike structure indicating, at least, one recent merger event. Through relations recently published in the literature, we obtained global parameters, such as $M_\mathrm{stellar}=9.32\times10^{11}$ M$\odot$ and $M_h=6.46\times10^{13}$ M$\odot$. Using public spectroscopic data, we derive stellar population parameters of the central region of the galaxy by the full spectral fitting technique. We have found that, this region, seems to be dominated for an old stellar population, in contrast to findings of young stellar populations from the literature.
 [10] arXiv:1711.08053 [pdf, other]

Title: Exolightning radio emission: the case study of HATP11bComments: Accepted to the Conference Proceedings of the 8th International Workshop on Planetary, Solar and Heliospheric Radio Emissions (PRE 8), held in Seggauberg near Leibnitz/Graz, Austria, October 2527, 2016. 12 pages, 2 figuresSubjects: Earth and Planetary Astrophysics (astroph.EP); Solar and Stellar Astrophysics (astroph.SR); Atmospheric and Oceanic Physics (physics.aoph); Geophysics (physics.geoph)
Lightning induced radio emission has been observed on solar system planets. Lecavelier des Etangs et al. [2013] carried out radio transit observations of the exoplanet HATP11b, and suggested a tentative detection of a radio signal. Here, we explore the possibility of the radio emission having been produced by lightning activity on the exoplanet, following and expanding the work of Hodos\'an et al. [2016a]. After a summary of our previous work [Hodos\'an et al. 2016a], we extend it with a parameter study. The lightning activity of the hypothetical storm is largely dependent on the radio spectral rolloff, $n$, and the flash duration, $\tau_\mathrm{fl}$. The bestcase scenario would require a flash density of the same order of magnitude as can be found during volcanic eruptions on Earth. On average, $3.8 \times 10^6$ times larger flash densities than the Earthstorms with the largest lightning activity is needed to produce the observed signal from HATP11b. Combined with the results of Hodos\'an et al. [2016a] regarding the chemical effects of planetwide thunderstorms, we conclude that future radio and infrared observations may lead to lightning detection on planets outside the solar system.
 [11] arXiv:1711.08110 [pdf, other]

Title: The SUrvey for Pulsars and Extragalactic Radio Bursts II: New FRB discoveries and their followupAuthors: S. Bhandari, E. F. Keane, E. D. Barr, A. Jameson, E. Petroff, S. Johnston, M. Bailes, N. D. R. Bhat, M. Burgay, S. BurkeSpolaor, M. Caleb, R. P. Eatough, C. Flynn, J. A. Green, F. Jankowski, M. Kramer, V.Venkatraman Krishnan, V. Morello, A. Possenti, B.Stappers, C. Tiburzi, W. van Straten, I. Andreoni, T. Butterley, P. Chandra, J. Cooke, A.Corongiu, D.M. Coward, V. S. Dhillon, R. Dodson, L. K. Hardy, E.J. Howell, P. Jaroenjittichai, A. Klotz, S. P. Littlefair, T. R. Marsh, M. Mickaliger, T. Muxlow, D. Perrodin, T. Pritchard, U. Sawangwit, T. Terai, N. Tominaga, P. Torne, T. Totani, A. Trois, D.Turpin, Y. Niino, R. W. Wilson, The ANTARES CollaborationComments: 21 pages, 8 figures and accepted for publication in MNRASSubjects: High Energy Astrophysical Phenomena (astroph.HE)
We report the discovery of four Fast Radio Bursts (FRBs) in the ongoing SUrvey for Pulsars and Extragalactic Radio Bursts (SUPERB) at the Parkes Radio Telescope: FRBs 150610, 151206, 151230 and 160102. Our realtime discoveries have enabled us to conduct extensive, rapid multimessenger followup at 12 major facilities sensitive to radio, optical, Xray, gammaray photons and neutrinos on time scales ranging from an hour to a few months postburst. No counterparts to the FRBs were found and we provide upper limits on afterglow luminosities. None of the FRBs were seen to repeat. Formal fits to all FRBs show hints of scattering while their intrinsic widths are unresolved in time. FRB 151206 is at low Galactic latitude, FRB 151230 shows a sharp spectral cutoff, and FRB 160102 has the highest dispersion measure (DM = $2596.1\pm0.3$ pc cm$^{3}$) detected to date. Three of the FRBs have high dispersion measures (DM >$1500$ pc cm$^{3}$), favouring a scenario where the DM is dominated by contributions from the Intergalactic Medium. The slope of the Parkes FRB source counts distribution with fluences $>2$ Jyms is $\alpha=2.2^{+0.6}_{1.2}$ and still consistent with a Euclidean distribution ($\alpha=3/2$). We also find that the allsky rate is $1.7^{+1.5}_{0.9}\times10^3$FRBs/($4\pi$ sr)/day above $\sim2$ Jyms and there is currently no strong evidence for a latitudedependent FRB skyrate.
 [12] arXiv:1711.08122 [pdf, other]

Title: Discovery of 21 New Changinglook AGNs in Northern SkyAuthors: Qian Yang, XueBing Wu, Xiaohui Fan, Linhua Jiang, Ian McGreer, Jinyi Shangguan, Su Yao, Bingquan Wang, Ravi Joshi, Richard Green, Feige Wang, Xiaotong Feng, Yuming Fu, Jinyi Yang, Yuanqi LiuComments: submitted to ApJSubjects: Astrophysics of Galaxies (astroph.GA); Cosmology and Nongalactic Astrophysics (astroph.CO)
The rare case of changinglook (CL) AGNs, with the appearance or disappearance of broad Balmer emission lines within a few years, challenges our understanding of the AGN unified model. We present a sample of 21 new CL AGNs at $0.08<z<0.58$. The new sample doubles the number of such objects known to date. These new CL AGNs were discovered by several ways, from repeat spectra in the SDSS, repeat spectra in the Large Sky Area MultiObject Fiber Spectroscopic Telescope (LAMOST) and SDSS, and from photometric variability and new spectroscopic observations. The estimated upper limits of transition timescale of the CL AGNs in this sample span from 0.9 to 13 years in restframe. The continuum flux in the optical and midinfrared becomes brighter when the CL AGNs turn on, or vice versa. Variations of more than 0.2 mag in the midinfrared $W1$ band, from the Widefield Infrared Survey Explorer (WISE), were detected in 15 CL AGNs during the transition. The optical and midinfrared variability is not consistent with the scenario of variable obscuration in 10 CL AGNs at higher than $3\sigma$ confidence level. We confirm a bluerwhenbrighter trend in the optical. However, the midinfrared colors $W1W2$ become redder when the objects become brighter in the $W1$ band, possibly due to a stronger hot dust contribution in the $W2$ band when the AGN activity becomes stronger. The physical mechanism of type transition is important for understanding the evolution of AGNs.
 [13] arXiv:1711.08131 [pdf, ps, other]

Title: Resolving the Internal Structure of CircumGalactic Medium using Gravitationally Lensed QuasarsAuthors: Suzuka Koyamada, Toru Misawa, Naohisa Inada, Masamune Oguri, Nobunari Kashikawa, Katsuya OkoshiComments: 13 pages, 8 figures, 3 tables, accepted for publication in ApJSubjects: Astrophysics of Galaxies (astroph.GA)
We study the internal structure of the CircumGalactic Medium (CGM), using 29 spectra of 13 gravitationally lensed quasars with image separation angles of a few arcseconds, which correspond to 100 pc to 10 kpc in physical distances. After separating metal absorption lines detected in the spectra into highions with ionization parameter (IP) $>$ 40 eV and lowions with IP $<$ 20 eV, we find that i) the fraction of absorption lines that are detected in only one of the lensed images is larger for lowions ($\sim$16%) than highions ($\sim$2%), ii) the fractional difference of equivalent widths ($EW$s) between the lensed images is almost same (${\rm d}EW$ $\sim$ 0.2) for both groups although the lowions have a slightly larger variation, and iii) weak lowion absorbers tend to have larger ${\rm d}EW$ compared to weak highion absorbers. We construct simple models to reproduce these observed properties and investigate the distribution of physical quantities such as size and location of absorbers, using some free parameters. Our best models for absorbers with highions and lowions suggest that i) an overall size of the CGM is at least $\sim$ 500 kpc, ii) a size of spherical clumpy cloud is $\sim$ 1 kpc or smaller, and iii) only highion absorbers can have diffusely distributed homogeneous component throughout the CGM. We infer that a high ionization absorber distributes almost homogeneously with a smallscale internal fluctuation, while a low ionization absorber consists of a large number of smallscale clouds in the diffusely distributed higher ionized region. This is the first result to investigate the internal smallscale structure of the CGM, based on the large number of gravitationally lensed quasar spectra.
 [14] arXiv:1711.08140 [pdf, ps, other]

Title: The MASIV Survey IV: relationship between intraday scintillation and intrinsic variability of radio AGNsAuthors: J. Y. Koay, J.P. Macquart, D. L. Jauncey, T. Pursimo, M. Giroletti, H. E. Bignall, J. E. J. Lovell, B. J. Rickett, L. KedzioraChudczer, R. Ojha, C. ReynoldsComments: 18 pages, 13 figures, 5 tables, resubmitted to MNRAS after minor revisionSubjects: Astrophysics of Galaxies (astroph.GA); High Energy Astrophysical Phenomena (astroph.HE)
We investigate the relationship between 5 GHz interstellar scintillation (ISS) and 15 GHz intrinsic variability of compact, radioselected AGNs drawn from the Microarcsecond ScintillationInduced Variability (MASIV) Survey and the Owens Valley Radio Observatory (OVRO) blazar monitoring program. We discover that the strongest scintillators at 5 GHz (modulation index, $m_5 \geq 0.02$) all exhibit strong 15 GHz intrinsic variability ($m_{15} \geq 0.1$). This relationship can be attributed mainly to the mutual dependence of intrinsic variability and ISS amplitudes on radio core compactness at $\sim 100\, \mu$as scales, and to a lesser extent, on their mutual dependences on source flux density, arcsecscale core dominance and redshift. However, not all sources displaying strong intrinsic variations show high amplitude scintillation, since ISS is also strongly dependent on Galactic lineofsight scattering properties. This observed relationship between intrinsic variability and ISS highlights the importance of optimizing the observing frequency, cadence, timespan and sky coverage of future radio variability surveys, such that these two effects can be better distinguished to study the underlying physics. For the full MASIV sample, we find that Fermidetected gammaray loud sources exhibit significantly higher 5 GHz ISS amplitudes than gammaray quiet sources. This relationship is weaker than the known correlation between gammaray loudness and the 15 GHz variability amplitudes, most likely due to jet opacity effects.
 [15] arXiv:1711.08143 [pdf]

Title: Iwahashi Zenbei's Sunspot Drawings in 1793 in JapanComments: 2017/11/16 accepted for publication in Solar PhysicsSubjects: Solar and Stellar Astrophysics (astroph.SR); History and Philosophy of Physics (physics.histph)
Three Japanese sunspot drawings associated with Iwahashi Zenbei (17561811) are shown here from contemporary manuscripts and woodprint documents with the relevant texts. We revealed the observational date of one of the drawings to be 26 August 1793, and the overall observations lasted for over a year. Moreover, we identified the observational site for the dated drawing at Fushimi in Japan. We then compared his observations with group sunspot number and raw group count from Sunspot Index and Longterm Solar Observations (SILSO) to reveal its data context, and concluded that these drawings filled the gaps in understanding due to the fragmental sunspots observations around 1793. These drawings are important as a clue to evaluate astronomical knowledge of contemporary Japan in the late 19 th century and are valuable as a nonEuropean observation, considering that most sunspot observations up to mid19 th century are from Europe.
 [16] arXiv:1711.08156 [pdf, ps, other]

Title: Examination of artifact in vector magnetic field SDO/HMI measurementsComments: 12 pages, 8 figuresSubjects: Solar and Stellar Astrophysics (astroph.SR)
In this paper, we came to conclusion that there is a significant systematic error in the SDO/HMI vector magnetic data, which reveals itself in a significant deviation of the lines of the knot magnetic fields from the radial direction. The value of this deviation demonstrates a clear dependence on the distance to the disk center. This paper suggests a method for correction of the vector magnetograms that eliminates the detected systematic error.
 [17] arXiv:1711.08161 [pdf, ps, other]

Title: Planetdriven spiral arms in protoplanetary disks: I. Formation mechanismComments: 16 pages, 14 figures, submitted to the ApJSubjects: Earth and Planetary Astrophysics (astroph.EP)
Protoplanetary disk simulations show that a single planet can excite more than one spiral arm, possibly explaining recent observations of multiple spiral arms in some systems. In this paper, we explain the mechanism by which a planet excites multiple spiral arms in a protoplanetary disk. Contrary to previous speculations, the formation of both primary and additional arms can be understood as a linear process when the planet mass is sufficiently small. A planet resonantly interacts with epicyclic oscillations in the disk, launching spiral wave modes around the Lindblad resonances. When a set of wave modes is in phase, they can constructively interfere with each other and create a spiral arm. More than one spiral arm can form because such constructive interference can occur for different sets of wave modes, with the exact number and launching position of spiral arms dependent on the planet mass as well as the disk temperature profile. Nonlinear effects become increasingly important as the planet mass increases, resulting in spiral arms with stronger shocks and thus larger pitch angles. This is found in common for both primary and additional arms. When a planet has a sufficiently large mass ($\gtrsim$ 3 thermal masses for $(h/r)_p=0.1$), only two spiral arms form interior to its orbit. The wave modes that would form a tertiary arm for smaller mass planets merge with the primary arm. Improvements in our understanding of the formation of spiral arms can provide crucial insights into the origin of observed spiral arms in protoplanetary disks.
 [18] arXiv:1711.08165 [pdf, ps, other]

Title: Discovery of molecular and atomic clouds associated with the gammaray supernova remnant Kesteven 79Authors: M. Kuriki, H. Sano, N. Kuno, M. Seta, Y. Yamane, T. Inaba, T. Nagaya, S. Yoshiike, K. Okawa, D. Tsutsumi, Y. Hattori, M. Khono, S. Fujita, A. Nishimura, A. Ohama, M. Matsuo, Y. Tsuda, K. Torii, T. Minamidani, T. Umemoto, G. Rowell, A. Bamba, K. Tachihara, Y. FukuiComments: 12 pages, 6 figures, 2 tables, submitted to The Astrophysical Journal (ApJ)Subjects: Astrophysics of Galaxies (astroph.GA); High Energy Astrophysical Phenomena (astroph.HE)
We carried out $^{12}$CO($J$ = 10) observations of the Galactic gammaray supernova remnant (SNR) Kesteven 79 using the Nobeyama Radio Observatory 45 m radio telescope, which has an angular resolution of $\sim20$ arcsec. We identified molecular and atomic gas interacting with Kesteven 79 whose radial velocity is $\sim80$ km s$^{1}$. The interacting molecular and atomic gases show good spatial correspondence with the Xray and radio shells, which have an expanding velocity structure with $\Delta V\sim4$ km s$^{1}$. The molecular gas associated with the radio and Xray peaks also exhibits a highintensity ratio of CO 32/10 $>$ 0.8, suggesting a kinematic temperature of $\sim100$ K, owing to heating by the supernova shock. We determined the kinematic distance to the SNR to be $\sim5.5$ kpc and the radius of the SNR to be $\sim8$ pc. The average interstellar proton density inside of the SNR is $\sim360$ cm$^{3}$, of which atomic protons comprise only $\sim10$ $\%$. Assuming a hadronic origin for the gammaray emission, the total cosmicray proton energy above 1 GeV is estimated to be $\sim5 \times 10^{48}$ erg.
 [19] arXiv:1711.08166 [pdf, ps, other]

Title: Planetdriven spiral arms in protoplanetary disks: II. ImplicationsComments: 14 pages, 10 figures, Figure 2 size reduced to meet the requirement, submitted to the ApJSubjects: Earth and Planetary Astrophysics (astroph.EP)
In Paper I (Bae & Zhu 2017), we explained how a planet excites multiple spiral arms in a protoplanetary disk. To examine whether various characteristics of observed spiral arms can be used to constrain the masses of unseen planets and their positions within their disks, we carry out twodimensional simulations varying planet mass and disk gas temperature. A larger number of spiral arms form with a smaller planet mass and a lower disk temperature. For a range of disk temperature characterized by the disk aspect ratio $0.04 \leq (h/r)_p \leq 0.15$, three or fewer spiral arms are excited interior to a planet's orbit when $M_p/M_* \gtrsim 3\times10^{4}$ and two spiral arms when $M_p/M_* \gtrsim 3\times10^{3}$. Exterior to a planet's orbit, multiple spiral arms can form only in cold disks with $(h/r)_p \lesssim 0.06$. Constraining the planet mass with the pitch angle of spiral arms requires accurate disk temperature measurements that might be challenging even with ALMA. However, the property that the pitch angle of planetdriven spiral arms decreases away from the planet can be a powerful diagnostic to determine whether the planet is located interior or exterior to the observed spirals. The armtoarm separations increase as a function of planet mass, consistent with previous studies; however, we find that the exact slope depends on disk temperature as well as the radial location where the armtoarm separations are measured. We apply these diagnostics to the spiral arms seen in MWC 758 and Elias 227. Finally, we discuss the possibility that Jupiter's core creates multiple pressure bumps in the solar nebula through spiral shocks, and show how it can help explain meteoritic properties.
 [20] arXiv:1711.08176 [pdf, ps, other]

Title: Causal propagation of signal in strangeon matterComments: Submitted to MNRASSubjects: High Energy Astrophysical Phenomena (astroph.HE)
The state equation of strangeon matter is very stiff due to the nonrelativistic nature of and the repulsing interaction between the particles, and pulsar masses as high as $\sim 3M_\odot$ would be expected. However, an adiabatic sound speed, $c_s=\sqrt{\partial P/\partial \rho}$, is usually superluminal for strangeon matter, and dynamic response of strangeon star (e.g., binary merger) could not be tractable in calculation. We examine signal propagation in strangeon matter, and calculate the propagation speed, $c_{\rm signal}$, in reality. It is found that as the causality condition is satisfied, i.e., $c_{\rm signal}<c$, and the signal speed as a function of stellar radius is presented.
 [21] arXiv:1711.08178 [pdf, ps, other]

Title: Peculiar Motions of Galaxy Clusters in the Regions of Superclusters of galaxiesComments: 16 pages, 6 figures, 3 tables, published in the Astrophysical Bulletin, 2017Subjects: Cosmology and Nongalactic Astrophysics (astroph.CO); Astrophysics of Galaxies (astroph.GA)
We present results of the study of peculiar motions of 57 clusters and groups of galaxies in the regions of the Corona Borealis (CrB), Bootes (Boo), Z5029/A1424, A1190, A1750/A1809 superclusters of galaxies and 20 galaxy clusters located beyond massive structures ($0.05<z<0.10$). Using the SDSS (Data Release 8) data, a sample of earlytype galaxies was compiled in the systems under study, their fundamental planes were built, and relative distances and peculiar velocities were determined. Within the galaxy superclusters, significant peculiar motions along the line of sight are observed with rms deviations of $652\pm50$~km s$^{1}$in CrB, $757\pm70$~km s$^{1}$in Boo. For the most massive A2065 cluster in the CrB supercluster, no peculiar velocity was found. Peculiar motions of other galaxy clusters can be caused by their gravitational interaction both with A\,2065 and with the A2142 supercluster. It has been found that there are two superclusters projected onto each other in the region of the Bootes supercluster with a radial velocity difference of about 4000~km s$^{1}$. In the Z5029/A1424 supercluster near the rich Z5029 cluster, the most considerable peculiar motions with a rms deviation of $1366\pm170$~km s$^{1}$ are observed. The rms deviation of peculiar velocities of 20 clusters that do not belong to largescale structures is equal to $0\pm20$~km s$^{1}$. The whole sample of the clusters under study has the mean peculiar velocity equal to $83\pm130$~km s$^{1}$ relative to the cosmic microwave background.
 [22] arXiv:1711.08183 [pdf, ps, other]

Title: 12C/13C isotopic ratios in redgiant stars of the open cluster NGC 6791Authors: László Szigeti, Szabolcs Mészáros, Verne V. Smith, Katia Cunha, Nadège Lagarde, Corinne Charbonnel, Matthew Shetrone, Marc Pinsonneault, Carlos Allende Prieto, J. G. FernándezTrincado, József Kovács, Sandro VillanovaComments: Accepted for publication in MNRAS, 9 pages, 4 figures, 2 tablesSubjects: Solar and Stellar Astrophysics (astroph.SR)
Carbon isotope ratios, along with carbon and nitrogen abundances, are derived in a sample of 11 redgiant members of one of the most metalrich clusters in the Milky Way, NGC 6791. The selected redgiants have a mean metallicity and standard deviation of [Fe/H]=+0.39+0.06 (Cunha et al. 2015). We used high resolution Hband spectra obtained by the SDSSIV Apache Point Observatory Galactic Evolution Experiment (APOGEE). The advantage of using highresolution spectra in the Hband is that lines of CO are well represented and their line profiles are sensitive to the variation of 12C/13C. Values of the 12C/13C ratio were obtained from a spectrum synthesis analysis. The derived 12C/13C ratios varied between 6.3 and 10.6 in NGC 6791, in agreement with the final isotopic ratios from thermohalineinduced mixing models. The ratios derived here are combined with those obtained for more metal poor redgiants from the literature to examine the correlation between 12C/13C, mass, metallicity and evolutionary status.
 [23] arXiv:1711.08206 [pdf, ps, other]

Title: The formation rate of short gammaray bursts and gravitational wavesComments: 29 pages, 8 figures, 2 tables, accepted for publication in ApJSubjects: High Energy Astrophysical Phenomena (astroph.HE); Cosmology and Nongalactic Astrophysics (astroph.CO)
In this paper, we study the luminosity function and formation rate of short gammaray bursts (sGRBs). Firstly, we derive the $E_pL_p$ correlation using 16 sGRBs with redshift measurements and determine the pseudo redshifts of 284 Fermi sGRBs. Then, we use the LyndenBell c$^$ method to study the luminosity function and formation rate of sGRBs without any assumptions. A strong evolution of luminosity $L(z)\propto (1+z)^{4.47}$ is found. After removing this evolution, the luminosity function is $ \Psi (L) \propto L_0 ^ { 0.29 \pm 0.01} $ for dim sGRBs and $ \psi (L) \propto L_0 ^ { 1.07 \pm 0.01} $ for bright sGRBs, with the break point $8.26 \times 10^{50} $ erg s$^{1}$. We also find that the formation rate decreases rapidly at $z<1.0$, which is different with previous works. The local formation rate of sGRBs is 7.53 events Gpc$^{3}$ yr$^{1}$. Considering the beaming effect, the local formation rate of sGRBs including offaxis sGRBs is $ 203.31^{+1152.09}_{135.54} $ events Gpc$^{3}$ yr$^{1}$. We also estimate that the event rate of sGRBs detected by the advanced LIGO and Virgo is $0.85^{+4.82}_{0.56} $ events yr$^{1}$ for NSNS binary.
 [24] arXiv:1711.08233 [pdf, other]

Title: A universal relation for the propeller mechanisms in magnetic rotating stars at different scalesAuthors: Sergio Campana (1), Luigi Stella (2), Sandro Mereghetti (3), Domitilla de Martino (4) ((1) INAFBrera, (2) INAFMonteporzio, (3) INAFIASF Milano, (4) INAFNapoli)Comments: 11 pages, 3 figures. Accepted for publication in A&ASubjects: High Energy Astrophysical Phenomena (astroph.HE)
Accretion of matter onto a magnetic, rotating object can be strongly affected by the interaction with its magnetic field. This occurs in a variety of astrophysical settings involving young stellar objects, white dwarfs, and neutron stars. As matter is endowed with angular momentum, its inflow toward the star is often mediated by an accretion disc. The pressure of matter and that originating from the stellar magnetic field balance at the magnetospheric radius: at smaller distances the motion of matter is dominated by the magnetic field, and funnelling towards the magnetic poles ensues. However, if the star, and thus its magnetosphere, is fast spinning, most of the inflowing matter will be halted at the magnetospheric radius by centrifugal forces, resulting in a characteristic reduction of the accretion luminosity. The onset of this mechanism, called the propeller, has been widely adopted to interpret a distinctive knee in the decaying phase of the light curve of several transiently accreting Xray pulsar systems. By comparing the observed luminosity at the knee for different classes of objects with the value predicted by accretion theory on the basis of the independently measured magnetic field, spinperiod, mass, and radius of the star, we disclose here a general relation for the onset of the propeller which spans about eight orders of magnitude in spin period and ten in magnetic moment. The parameterdependence and normalisation constant that we determine are in agreement with basic accretion theory.
 [25] arXiv:1711.08236 [pdf, other]

Title: Enceladus's crust as a nonuniform thin shell: I Tidal deformationsAuthors: Mikael BeutheComments: 71 pages, 12 figures, 5 tablesJournalref: Icarus 302 (2018) 145174Subjects: Earth and Planetary Astrophysics (astroph.EP); Geophysics (physics.geoph); Space Physics (physics.spaceph)
The geologic activity at Enceladus's south pole remains unexplained, though tidal deformations are probably the ultimate cause. Recent gravity and libration data indicate that Enceladus's icy crust floats on a global ocean, is rather thin, and has a strongly nonuniform thickness. Tidal effects are enhanced by crustal thinning at the south pole, so that realistic models of tidal tectonics and dissipation should take into account the lateral variations of shell structure. I construct here the theory of nonuniform viscoelastic thin shells, allowing for depthdependent rheology and large lateral variations of shell thickness and rheology. Coupling to tides yields two 2D linear partial differential equations of the 4th order on the sphere which take into account selfgravity, density stratification below the shell, and core viscoelasticity. If the shell is laterally uniform, the solution agrees with analytical formulas for tidal Love numbers; errors on displacements and stresses are less than 5% and 15%, respectively, if the thickness is less than 10% of the radius. If the shell is nonuniform, the tidal thin shell equations are solved as a system of coupled linear equations in a spherical harmonic basis. Compared to finite element models, thin shell predictions are similar for the deformations due to Enceladus's pressurized ocean, but differ for the tides of Ganymede. If Enceladus's shell is conductive with isostatic thickness variations, surface stresses are approximately inversely proportional to the local shell thickness. The radial tide is only moderately enhanced at the south pole. The combination of crustal thinning and convection below the poles can amplify south polar stresses by a factor of 10, but it cannot explain the apparent time lag between the maximum plume brightness and the opening of tiger stripes. In a second paper, I will study tidal dissipation in a nonuniform crust.
 [26] arXiv:1711.08254 [pdf, ps, other]

Title: Revised Models of Interstellar Nitrogen Isotopic FractionationComments: Accepted for publication in MNRAS, 3 figuresSubjects: Astrophysics of Galaxies (astroph.GA)
Nitrogenbearing molecules in cold molecular clouds exhibit a range of isotopic fractionation ratios and these molecules may be the precursors of $^{15}$N enrichments found in comets and meteorites. Chemical model calculations indicate that atommolecular ion and ionmolecule reactions could account for most of the fractionation patterns observed. However, recent quantumchemical computations demonstrate that several of the key processes are unlikely to occur in dense clouds. Related model calculations of dense cloud chemistry show that the revised $^{15}$N enrichments fail to match observed values. We have investigated the effects of these reaction rate modifications on the chemical model of Wirstr\"{o}m et al. (2012) for which there are significant physical and chemical differences with respect to other models. We have included $^{15}$N fractionation of CN in neutralneutral reactions and also updated rate coefficients for key reactions in the nitrogen chemistry. We find that the revised fractionation rates have the effect of suppressing $^{15}$N enrichment in ammonia at all times, while the depletion is even more pronounced, reaching $^{14}$N/$^{15}$N ratios of >2000. Taking the updated nitrogen chemistry into account, no significant enrichment occurs in HCN or HNC, contrary to observational evidence in dark clouds and comets, although the $^{14}$N/$^{15}$N ratio can still be below 100 in CN itself. However, such low CN abundances are predicted that the updated model falls short of explaining the bulk $^{15}$N enhancements observed in primitive materials. It is clear that alternative fractionating reactions are necessary to reproduce observations, so further laboratory and theoretical studies are urgently needed.
 [27] arXiv:1711.08266 [pdf, other]

Title: HighEnergy Neutrino Astronomy: where do we stand, where do we go?Authors: Christian SpieringComments: Talk given at the occasion of the 50th anniversary of the Baksan LaboratorySubjects: High Energy Astrophysical Phenomena (astroph.HE)
With the identification of a diffuse flux of astrophysical ("cosmic") neutrinos in the TeVPeV energy range, IceCube has opened a new window to the Universe. However, the corresponding cosmic landscape is still uncharted: so far, the observed flux does not show any clear association with known source classes. In the present talk, I sketch the way from BaikalNT200 to IceCube and summarize IceCube's recent astrophysics results. Finally, I describe the present projects to build even larger detectors: GVD in Lake Baikal, KM3NeT in the Mediterranean Sea and IceCubeGen2 at the South Pole. These detectors will allow studying the highenergy neutrino sky in much more detail than the present arrays permit.
 [28] arXiv:1711.08286 [pdf, other]

Title: CMB constraints on running nonGaussianityComments: 19 pages, 8 figuresSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO)
We develop a complete set of tools for CMB forecasting, simulation and estimation of primordial running bispectra, arising from a variety of curvaton and singlefield (DBI) models of Inflation. We validate our pipeline using mock CMB running nonGaussianity realizations and test it on real data by obtaining experimental constraints on the $f_{\rm NL}$ running spectral index, $n_{\rm NG}$, using WMAP 9year data. Our final bounds (68\% C.L.) read $0.3< n_{\rm NG}<1.7$, $0.3< n_{\rm NG}<1.3$, $0.9<n_{\rm NG}<1.0$ for the singlefield curvaton, twofield curvaton and DBI scenarios, respectively. We show forecasts and discuss potential improvements on these bounds, using Planck and future CMB surveys.
 [29] arXiv:1711.08323 [pdf, other]

Title: Extragalactic diffuse gammarays from dark matter annihilation: revised prediction and full modelling uncertaintiesComments: 21 pages + appendix, 10 figuresSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); High Energy Astrophysical Phenomena (astroph.HE)
Recent highenergy data from FermiLAT on the diffuse gammabackground (DGRB) have been used to set among the best constraints on annihilating TeV cold dark matter (DM) candidates. In order to assess the robustness of these limits, we revisit and update the calculation of the isotropic extragalactic gammaray intensity from DM annihilation. The emission from halos with masses $\geq10^{10}\,M_{\odot}$ provides a robust lower bound on the predicted intensity. The intensity including smaller halos whose properties are extrapolated from their higher mass counterparts is typically 5 times higher, and boost from subhalos yields an additional factor ~1.5. We also rank the uncertainties from all ingredients and provide a detailed error budget in table 1. Overall, our fiducial intensity is a factor 5 lower than the one derived by the FermiLAT collaboration for their latest analysis. This indicates that the limits set on extragalactic DM annihilations could be relaxed by the same factor. We also calculate the expected intensity for selfinteracting dark matter (SIDM) in massive halos and find the emission reduced by a factor 3 compared to the collisionless counterpart. The next release of the CLUMPY code will provide all the tools necessary to reproduce and ease future improvements of this prediction.
 [30] arXiv:1711.08327 [pdf, other]

Title: Tomography of cool giant and supergiant star atmospheres. I. Validation of the methodComments: 12 pages, 17 figuresSubjects: Solar and Stellar Astrophysics (astroph.SR)
Cool giant and supergiant star atmospheres are characterized by complex velocity fields originating from convection and pulsation processes which are not fully understood yet. The velocity fields impact the formation of spectral lines, which thus contain information on the dynamics of stellar atmospheres. The tomographic method allows to recover the distribution of the component of the velocity field projected on the line of sight at different optical depths in the stellar atmosphere. The computation of the contribution function to the line depression aims at correctly identifying the depth of formation of spectral lines in order to construct numerical masks probing spectral lines forming at different optical depths. The tomographic method is applied to 1D model atmospheres and to a realistic 3D radiative hydrodynamics simulation performed with CO5BOLD in order to compare their spectral line formation depths and velocity fields. In 1D model atmospheres, each spectral line forms in a restricted range of optical depths. On the other hand, in 3D simulations, the line formation depths are spread in the atmosphere mainly because of temperature and density inhomogeneities. Comparison of CCF profiles obtained from 3D synthetic spectra with velocities from the 3D simulation shows that the tomographic method correctly recovers the distribution of the velocity component projected on the line of sight in the atmosphere.
 [31] arXiv:1711.08347 [pdf, ps, other]

Title: Deriving HighPrecision Radial VelocitiesAuthors: Pedro FigueiraComments: Lecture presented at the IVth Azores International Advanced School in Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in July 2016Subjects: Earth and Planetary Astrophysics (astroph.EP)
This chapter describes briefly the key aspects behind the derivation of precise radial velocities. I start by defining radial velocity precision in the context of astrophysics in general and exoplanet searches in particular. Next I discuss the different basic elements that constitute a spectrograph, and how these elements and overall technical choices impact on the derived radial velocity precision. Then I go on to discuss the different wavelength calibration and radial velocity calculation techniques, and how these are intimately related to the spectrograph's properties. I conclude by presenting some interesting examples of planets detected through radial velocity, and some of the newgeneration instruments that will push the precision limit further.
 [32] arXiv:1711.08371 [pdf, other]

Title: Searching for Xray Pulsations from Neutron Stars Using NICERComments: 4 pages, to appear in Proceedings of IAU Symposium 337: Pulsar Astrophysics  The Next 50 YearsSubjects: High Energy Astrophysical Phenomena (astroph.HE)
The Neutron Star Interior Composition Explorer (NICER) presents an exciting new capability for exploring the modulation properties of Xray emitting neutron stars, including large area, low background, extremely precise absolute event time stamps, superb lowenergy response and flexible scheduling. The Pulsation Searches and Multiwavelength Coordination working group has designed a 2.5 Ms observing program to search for emission and characterize the modulation properties of about 30 known or suspected neutron star sources across a number of source categories. A key early goal will be to search for pulsations from millisecond pulsars that might exhibit thermal pulsations from the surface suitable for pulse profile modeling to constrain the neutron star equation of state. In addition, we will search for pulsations from transitional millisecond pulsars, isolated neutron stars, lowmass Xray binaries (LMXBs), accretionpowered millisecond pulsars, central compact objects and other sources. We present our science plan and initial results from the first months of the NICER mission, including the discovery of pulsations from the millisecond pulsar J12311411.
 [33] arXiv:1711.08383 [pdf, ps, other]

Title: SuperFlaring Active Region 12673 Has One of the Fastest Magnetic Flux Emergence Ever ObservedComments: Accepted to the Research Notes of the AASSubjects: Solar and Stellar Astrophysics (astroph.SR)
The flux emergence rate of AR 12673 is greater than any values reported in the literature of which we are aware.
 [34] arXiv:1711.08386 [pdf, ps, other]

Title: Reduced Order Modelling in searches for continuous gravitational waves  I. barycentering time delaysComments: 11 pages, 8 figuresSubjects: High Energy Astrophysical Phenomena (astroph.HE); General Relativity and Quantum Cosmology (grqc)
The frequencies and phases of emission from extrasolar sources, as measured by Earthbound observers, are modulated due to the Doppler motions of the observer with respect to the source, and through relativistic effects. These modulations depend critically on the skylocation of the source. Precise knowledge of the modulations is required if wanting to coherently track the phase of a source over long observation times, for example in pulsar timing, or searches for continuous gravitational wave sources. The modulations can be modelled as a skylocation and time dependent time delay that converts arrival times at the observer to the inertial frame of the source. In many cases this inertial frame can be the solar system barycentre (SSB). We study the use of Reduced Order Modelling for speeding up the calculation of the time delay between an observer and the SSB for any skylocation and for coherent observations spanning one year. We find that the time delay model can be decomposed into just four basis vectors, which can be used to reconstruct the time delay for any skylocation to subnanosecond accuracy. When compared to the standard routines for time delay calculation used in gravitational wave searches, the use of the reduced basis can lead to a speedup factor of 30 times. We have also studied the components of equivalent time delays for sources in binary systems. For these, assuming eccentricities less than 0.25, we can reconstruct the delays to within 100s of nanoseconds, with best case speedups of a factor of 10, or factors of two when having to interpolate the basis to different orbital periods or time stamps. In longduration phasecoherent searches for sources with large skyposition uncertainties, or binary parameter uncertainties, these speedups could allow enhancements in their scopes without large additional computational burdens.
 [35] arXiv:1711.08394 [pdf, other]

Title: Rotationally modulated photometric variations in B supergiants?Authors: Alexandre DavidUraz (1 and 2), Gregg Wade (3), Anthony Moffat (4), Stan Owocki (1), Véronique Petit (1), the BRITE team ((1) University of Delaware, (2) Florida Institute of Technology, (3) Royal Military College of Canada, (4) Université de Montréal)Comments: 6 pages, 3 figures, to be published in the proceedings of the 3rd BRITE Science Conference held in SaintMicheldesSaints (QC, Canada), 2017 August 710  Proceedings of the Polish Astronomical SocietySubjects: Solar and Stellar Astrophysics (astroph.SR)
In this contribution, we present BRITE observations of the earlyB supergiants $\epsilon$ Ori and $\kappa$ Ori. We perform a preliminary analysis of the data acquired over the first two Orion observing runs. We evaluate whether they are compatible with corotating bright spots and discuss the challenges of such an approach.
 [36] arXiv:1711.08433 [pdf, other]

Title: Modelling the atmospheric composition of warm exoplanetsComments: Submitted to Experimental Astronomy, ARIEL Special IssueSubjects: Earth and Planetary Astrophysics (astroph.EP)
Since the discovery of the first extrasolar planet more than twenty years ago, we have discovered more than three thousand planets orbiting stars other than the Sun. Current observational instruments (on board the Hubble Space Telescope, Spitzer, and on groundbased facilities) allowed the scientific community to obtain important information on the physical and chemical properties of these planets. However, for a more indepth characterisation of these worlds, more powerful telescopes are needed. Thanks to the high sensitivity of their instruments, the next generation of space observatories (e.g. James Webb Space Telescope, ARIEL) will provide observations of unprecedented quality, allowing us to extract far more information than what was previously possible. Such high quality observations will provide constraints on theoretical models of exoplanet atmospheres and lead to a greater understanding of the physics and chemistry. Important modelling efforts have been carried out during the past few years, showing that numerous parameters and processes (such as the element abundances, temperature, mixing, etc.) are likely to effect the atmospheric composition of exoplanets and subsequently the observable spectra. In this manuscript, we review the different parameters that can influence the molecular composition of exoplanet atmospheres. We also consider future developments that are necessary to improve atmospheric models, driven by the need to interpret the available observations and show how ARIEL is going to improve our view and characterisation of exoplanet atmospheres.
 [37] arXiv:1711.08434 [pdf, other]

Title: Neutrino Mass Priors for Cosmology from Random MatricesComments: 16+2 pages, two column, 7 figures, 2 tablesSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); High Energy Physics  Phenomenology (hepph)
Cosmological measurements of structure are placing increasingly strong constraints on the sum of the neutrino masses, $\Sigma m_\nu$, through Bayesian inference. Because these constraints depend on the choice for the prior probability $\pi(\Sigma m_\nu)$, we argue that this prior should be motivated by fundamental physical principles rather than the ad hoc choices that are common in the literature. The first step in this direction is to specify the prior directly at the level of the neutrino mass matrix $M_\nu$, since this is the parameter appearing in the Lagrangian of the particle physics theory. Thus by specifying a probability distribution over $M_\nu$, and by including the known squared mass splittings, we predict a theoretical probability distribution over $\Sigma m_\nu$ that we interpret as a Bayesian prior probability $\pi(\Sigma m_\nu)$. We find that $\pi(\Sigma m_\nu)$ peaks close to the smallest $\Sigma m_\nu$ allowed by the measured mass splittings, roughly $0.06 \, {\rm eV}$ ($0.1 \, {\rm eV}$) for normal (inverted) ordering, due to the phenomenon of eigenvalue repulsion in random matrices. We consider three models for neutrino mass generation: Dirac, Majorana, and Majorana via the seesaw mechanism; differences in the predicted priors $\pi(\Sigma m_\nu)$ allow for the possibility of having indications about the physical origin of neutrino masses once sufficient experimental sensitivity is achieved. We present fitting functions for $\pi(\Sigma m_\nu)$, which provide a simple means for applying these priors to cosmological constraints on the neutrino masses or marginalizing over their impact on other cosmological parameters.
 [38] arXiv:1711.08438 [pdf, other]

Title: Simulating the galaxy cluster "El Gordo": gas motion, kinetic SunyaevZel'dovich signal, and Xray line featuresAuthors: Congyao Zhang (1, 2), Qingjuan Yu (2), Youjun Lu (3, 4) ((1) MPA, (2) KIAA, (3) NAOC, (4) UCAS)Comments: 10 pages, 6 figures, submitted to ApJSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); Astrophysics of Galaxies (astroph.GA)
The massive galaxy cluster "El Gordo" (ACTCL J01024915) is a rare merging system with a high collision speed suggested by multiwavelength observations and the theoretical modeling. Zhang et al. (2015) propose two types of mergers, a nearly headon merger and an offaxis merger with a large impact parameter, to reproduce most of the observational features of the cluster, by using numerical simulations. The different merger configurations of the two models result in different gas motion in the simulated clusters. In this paper, we predict the kinetic SunyaevZel'dovich (kSZ) effect, the relativistic correction of the thermal SunyaevZel'dovich (tSZ) effect, and the Xray spectrum of this cluster, based on the two proposed models. We find that (1) the amplitudes of the kSZ effect resulting from the two models are both on the order of $\Delta T/T\sim10^{5}$; but their morphologies are different, which trace the different lineofsight velocity distributions of the systems; (2) the relativistic correction of the tSZ effect around $240 {\rm\,GHz}$ can be possibly used to constrain the temperature of the hot electrons heated by the shocks; and (3) the shift between the Xray spectral lines emitted from different regions of the cluster can be significantly different in the two models. The shift and the line broadening can be up to $\sim 25{\rm\,eV}$ and $50{\rm\,eV}$, respectively. We expect that future observations of the kSZ effect and the Xray spectral lines (e.g., by ALMA, XARM) will provide a strong constraint on the gas motion and the merger configuration of ACTCL J01024915.
 [39] arXiv:1711.08441 [pdf, other]

Title: Reconstruction of a directiondependent primordial power spectrum from Planck CMB dataComments: 32 pages, 22 figures, 6 tablesSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
We consider the possibility that the primordial curvature perturbation is directiondependent. To first order this is parameterised by a quadrupolar modulation of the power spectrum and results in statistical anisotropy of the cosmic microwave background, which can be quantified using the bipolar spherical harmonic representation. We compute these for the Planck Release 2 SMICA map and use them to infer the quadrupole modulation of the primordial power spectrum which, going beyond previous work, we allow to be scaledependent. Uncertainties are estimated from Planck FFP9 simulations. Consistent with the Planck collaboration's findings, we find no evidence for a constant quadrupole modulation, nor one scaling with wave number as a power law. However our nonparametric reconstruction suggests several spectral features. When a constant quadrupole modulation is fitted to data limited to the wave number range $0.005 \leq k/\mathrm{Mpc}^{1} \leq 0.008$, we find that its preferred direction is aligned with the cosmic hemispherical asymmetry. To determine the statistical significance we construct two different test statistics and test them on our reconstructions from data, against reconstructions of realisations of noise only. With a test statistic sensitive only to the amplitude of the modulation, the reconstructions are unusual at $2.5\sigma$ significance in the full wave number range, but at $2.2\sigma$ when limited to the intermediate wave number range $0.008 \leq k/\mathrm{Mpc}^{1} \leq 0.074$. With the second test statistic, sensitive also to direction, the reconstructions are unusual with $4.6\sigma$ significance, dropping to $2.7 \sigma$ for the intermediate wave number range. Our approach is easily generalised to include other data sets such as polarisation, largescale structure and forthcoming 21cm line observations which will enable these anomalies to be investigated further.
Crosslists for Thu, 23 Nov 17
 [40] arXiv:1711.06628 (crosslist from grqc) [pdf, ps, other]

Title: Probing extra dimensions with gravitational and electromagnetic signals from compact mergersComments: 4 pagesSubjects: General Relativity and Quantum Cosmology (grqc); Cosmology and Nongalactic Astrophysics (astroph.CO)
The search for extra dimensions is a challenging endeavor to probe physics beyond the Standard Model. The joint detection of gravity waves (GW) and electromagnetic (EM) signals from the merging of a binary system of compact objects like a neutron star (NS) can help constrain the geometry of extra dimensions. In particular, if our observable Universe is a 3+1 hypersurface or brane embedded in a higher 4+1 Antide Sitter (AdS$_5$) spacetime, in which gravity is the only field that propagates through the infinite bulk space while any other field is confined on the brane, then GW and EM signals between two points on the brane would in general travel different paths. This would result in a time lag between the detection of GW and EM signals emitted simultaneously from the same source, with the apparent measurement of a "superluminous" GW speed. Assuming the standard $\Lambda$Cold Dark Matter ($\Lambda$CDM) scenario, we set a bound on the AdS$_5$ radius of curvature $\ell \lesssim 140\,$kpc, using the time lag $\delta t < 1.7\,$s between the measurement of the event GW170817 by the LIGO/VIRGO collaborations and the GRB170817A signal detected by the Fermi Gammaray Burst Monitor collaboration, both associated with a binary NSNS infall.
 [41] arXiv:1711.07700 (crosslist from hepth) [pdf, other]

Title: Transitions between topologically nontrivial configurationsComments: 5 pages, 2 figures; Proceedings of the 3rd International Conference on Particle Physics and Astrophysics, Moscow, 25 October 2017Subjects: High Energy Physics  Theory (hepth); Cosmology and Nongalactic Astrophysics (astroph.CO)
We study formation and evolution of solitons within a model with two real scalar fields with the potential having a saddle point. The set of these configurations can be split into disjoint equivalence classes. We give a simple expression for the winding number of an arbitrary closed loop in the field space and discuss the evolution scenarios that change the winding number. These nontrivial field configurations lead to formation of the domain walls in the threedimensional physical space.
 [42] arXiv:1711.07815 (crosslist from quantph) [pdf, other]

Title: Quantum chaos of dark matter in the Solar SystemAuthors: D.L.ShepelyanskyComments: 5 pages, 2 figuresSubjects: Quantum Physics (quantph); Earth and Planetary Astrophysics (astroph.EP); Disordered Systems and Neural Networks (condmat.disnn); Chaotic Dynamics (nlin.CD)
We perform timedependent analysis of quantum dynamics of dark matter particles in the Solar System. It is shown that this problem has similarities with a microwave ionization of Rydberg atoms studied previously experimentally and analytically. On this basis it is shown that the quantum effects for chaotic dark matter dynamics become significant for dark matter mass ratio to electron mass being smaller than $2 \times 10^{15}$. Below this border multiphoton diffusion over Rydberg states of dark matter atom becomes exponentially localized in analogy with the Anderson localization in disordered solids. The life time of dark matter in the Solar System is determined in dependence on mass ratio in the localized phase and a few photon ionization regime. Various implications of these quantum results are discussed for the capture of dark matter from Galaxy and its steadystate density distribution.
 [43] arXiv:1711.07895 (crosslist from hepph) [pdf, ps, other]

Title: Chiral Tensor Particles in the Early Universe  Present StatusComments: 7 pages, 2 figures, research article, Preprint of an article published in MPLA's, Volume No.32, Issue No. 34, 2017Subjects: High Energy Physics  Phenomenology (hepph); Cosmology and Nongalactic Astrophysics (astroph.CO)
In this work an update of the cosmological role and place of the chiral tensor particles in the Universe history is provided. We discuss an extended model with chiral tensor particles. The influence of these particles on the early Universe evolution is studied. Namely, the increase of the Universe expansion rate caused by the additional particles in this extended model is calculated, their characteristic interactions with the particles of the hot Universe plasma are studied and the corresponding times of their creation, scattering, annihilation and decay are estimated for accepted values of their masses and couplings, based on the recent experimental constraints. The period of abundant presence of these particles in the Universe evolution is determined.
 [44] arXiv:1711.08015 (crosslist from physics.spaceph) [pdf]

Title: The Cosmic Ray Boron/Carbon Ratio Measured at Voyager and at AMS2 from 10 MeV/nuc up to ~1 TeV/nuc and a Comparison With Propagation CalculationsComments: 15 pages, 2 tables, 3 figuresSubjects: Space Physics (physics.spaceph); High Energy Astrophysical Phenomena (astroph.HE)
We have used new measurements of the B/C ratio in galactic cosmic rays at both low and high energies by the Voyager and AMS2 spacecraft, respectively, along with propagation calculations using a truncated LBM to examine the implications of these new measurements over an extended energy range from a few MeV/nuc to 1 TeV/nuc. We find that the predictions from both the truncated LBM and the Diffusive Reacceleration model for GALPROP both agree with the Voyager and AMS2 measurements of the B/C ratio to within +/ 10 percent throughout the entire energy range from 50 MeV/nuc to 1 TeV/nuc. The two propagation approaches also agree with each other to within +/10 percent or less throughout this energy range. In effect a diffusion model, without significant additional acceleration, provides a match within +/10 percent to the combined data from Voyager 1 and AMS2 on the B/C ratio from 50 MeV/nuc to 1 TeV/nuc. The B/C ratio below 50 MeV/nuc measured at V1 exceeds the predictions of both propagation models by as much as 3 sigma in the data measurement errors.
 [45] arXiv:1711.08026 (crosslist from grqc) [pdf, ps, other]

Title: Cosmic acceleration in asymptotically Ricci flat UniverseComments: 12 pages, 18 figures in 9 panelsSubjects: General Relativity and Quantum Cosmology (grqc); Cosmology and Nongalactic Astrophysics (astroph.CO)
We analyze the evolution of a FriedmannRobertsonWalker spacetime within the framework of $f(R)$ metric gravity using an exponential model. We show that $f(R)$ gravity may lead to a vanishing effective cosmological constant in the far future (i.e. $R\rightarrow 0$) and yet produce a transient accelerated expansion at present time with a potentially viable cosmological history. This is in contrast with several $f(R)$ models which, while viable, produce in general a nonvanishing effective cosmological constant asymptotically in time ($R\rightarrow 4\Lambda_{\rm eff}$). We also show that relativistic {stars in asymptotically flat spacetimes can be supported within this framework without encountering any singularity, notably in the Ricci scalar $R$.
 [46] arXiv:1711.08119 (crosslist from hepex) [pdf, other]

Title: Measurement of the multiTeV neutrino cross section with IceCube using Earth absorptionAuthors: IceCube Collaboration: M. G. Aartsen, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, I. Al Samarai, D. Altmann, K. Andeen, T. Anderson, I. Ansseau, G. Anton, C. Argüelles, J. Auffenberg, S. Axani, H. Bagherpour, X. Bai, J. P. Barron, S. W. Barwick, V. Baum, R. Bay, J. J. Beatty, J. Becker Tjus, K.H. Becker, S. BenZvi, D. Berley, E. Bernardini, D. Z. Besson, G. Binder, D. Bindig, E. Blaufuss, S. Blot, C. Bohm, M. Börner, F. Bos, D. Bose, S. Böser, O. Botner, J. Bourbeau, F. Bradascio, J. Braun, L. Brayeur, M. Brenzke, H.P. Bretz, S. Bron, J. BrosteanKaiser, A. Burgman, T. Carver, J. Casey, M. Casier, E. Cheung, D. Chirkin, A. Christov, K. Clark, L. Classen, S. Coenders, G. H. Collin, J. M. Conrad, D. F. Cowen, R. Cross, M. Day, J. P. A. M. de André, C. De Clercq, et al. (254 additional authors not shown)Comments: Preprint version of Nature paper 10.1038/nature24459Subjects: High Energy Physics  Experiment (hepex); High Energy Astrophysical Phenomena (astroph.HE); Nuclear Experiment (nuclex)
Neutrinos interact only very weakly, so they are extremely penetrating. However, the theoretical neutrinonucleon interaction cross section rises with energy such that, at energies above 40 TeV, neutrinos are expected to be absorbed as they pass through the Earth. Experimentally, the cross section has been measured only at the relatively low energies (below 400 GeV) available at neutrino beams from accelerators \cite{Agashe:2014kda, Formaggio:2013kya}. Here we report the first measurement of neutrino absorption in the Earth, using a sample of 10,784 energetic upwardgoing neutrinoinduced muons observed with the IceCube Neutrino Observatory. The flux of highenergy neutrinos transiting long paths through the Earth is attenuated compared to a reference sample that follows shorter trajectories through the Earth. Using a fit to the twodimensional distribution of muon energy and zenith angle, we determine the cross section for neutrino energies between 6.3 TeV and 980 TeV, more than an order of magnitude higher in energy than previous measurements. The measured cross section is $1.30^{+0.21}_{0.19}$ (stat.) $^{+0.39}_{0.43}$ (syst.) times the prediction of the Standard Model \cite{CooperSarkar:2011pa}, consistent with the expectation for charged and neutral current interactions. We do not observe a dramatic increase in the cross section, expected in some speculative models, including those invoking new compact dimensions \cite{AlvarezMuniz:2002ga} or the production of leptoquarks \cite{Romero:2009vu}.
 [47] arXiv:1711.08125 (crosslist from hepth) [pdf, ps, other]

Title: Ghostfree theory with thirdorder time derivativesComments: 5 pagesSubjects: High Energy Physics  Theory (hepth); Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
As the first step to extend our understanding of higherderivative theories, within the framework of analytic mechanics of interacting particles, we construct a ghostfree theory involving thirdorder time derivative in Lagrangian. We clarify that there is a crucial difference in construction from uptosecondorderderivative theories. While eliminating linear momentum terms in the Hamiltonian is necessary and sufficient to kill the ghosts associated with the higher derivatives for the Lagrangian with up to secondorder derivatives, this is necessary but not sufficient for the Lagrangian with higher than secondorder derivatives. We demonstrate that even after eliminating the linear momentum terms ghosts are still lurking and they need to be removed appropriately to make Lagrangian free from the ghosts. We clarify a set of ghostfree conditions under which we show that the Hamiltonian is bounded, and that equations of motion are reducible into a secondorder system.
 [48] arXiv:1711.08270 (crosslist from hepph) [pdf, other]

Title: Natural cliff inflationComments: 5 pages, 2 figuresSubjects: High Energy Physics  Phenomenology (hepph); Cosmology and Nongalactic Astrophysics (astroph.CO); High Energy Physics  Theory (hepth)
We propose a novel scenario of inflation, in which the inflaton is identified as the lightest mode of an angular field in a compactified fifth dimension. The periodic effective potential exhibits exponentially flat plateaus, so that a subPlanckian field excursion without hilltop initial conditions is naturally realized. We can obtain consistent predictions with observations on the spectral index and the tensortoscalar ratio.
 [49] arXiv:1711.08298 (crosslist from grqc) [pdf, other]

Title: Black hole superradiance and polarizationdependent bending of lightComments: Bulk of 29 pages + 11 figuresSubjects: General Relativity and Quantum Cosmology (grqc); High Energy Astrophysical Phenomena (astroph.HE); High Energy Physics  Phenomenology (hepph)
An inhomogeneous pseudoscalar field configuration behaves like an optically active medium. Consequently, if a light ray passes through an axion cloud surrounding a Kerr black hole, it may experience a polarizationdependent bending. We explore the size and relevance of such effect considering both the QCD axion and a generic axionlike particle.
 [50] arXiv:1711.08317 (crosslist from hepph) [pdf, ps, other]

Title: Light meson gas in the QCD vacuum and oscillating UniverseComments: 30 pages, 17 figuresSubjects: High Energy Physics  Phenomenology (hepph); High Energy Astrophysical Phenomena (astroph.HE)
We have developed a phenomenological effective quantumfield theoretical model describing the "hadron gas" of the lightest pseudoscalar mesons, scalar {\sigma}meson and {\sigma}vacuum, i.e. the expectation value of the {\sigma}field, at finite temperatures. The corresponding thermodynamic approach was formulated in terms of the generating functional derived from the effective Lagrangian providing the basic thermodynamic information about the "meson plasma + QCD condensate" system. This formalism enables us to study the QCD transition from the hadron phase with direct implications for cosmological evolution. Using the hypothesis about a positivelydefinite QCD vacuum contribution stochastically produced in early universe, we show that the universe could undergo a series of oscillations during the QCD epoch before resuming unbounded expansion.
 [51] arXiv:1711.08370 (crosslist from hepth) [pdf, other]

Title: Fluctuations through a Vibrating BounceComments: 17 pages, 5 figuresSubjects: High Energy Physics  Theory (hepth); Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
We study the evolution of cosmological perturbations in a nonsingular bouncing cosmology with a bounce phase which has superimposed oscillations of the scale factor. We identify length scales for which the final spectrum of fluctuations obtains imprints of the nontrivial bounce dynamics. These imprints in the spectrum are manifested in the form of damped oscillation features at scales smaller than a characteristic value and an increased reddening of the spectrum at all the scales as the number of small bounces increases.
 [52] arXiv:1711.08372 (crosslist from grqc) [pdf, ps, other]

Title: Black branes and black strings in the astrophysical and cosmological contextComments: 7 pages, no figures and tablesSubjects: General Relativity and Quantum Cosmology (grqc); Cosmology and Nongalactic Astrophysics (astroph.CO); High Energy Physics  Theory (hepth)
We consider KaluzaKlein models where internal spaces are compact flat or curved Einstein spaces. This background is perturbed by a compact gravitating body with the dustlike equation of state (EoS) in the external/our space and an arbitrary EoS parameter $\Omega$ in the internal space. Without imposing any restrictions on the form of the perturbed metric and the distribution of the perturbed energy densities, we perform the general analysis of the Einstein and conservation equations in the weakfield limit. All conclusions follow from this analysis. For example, we demonstrate that the perturbed model is static and perturbed metric preserves the blockdiagonal form. In a particular case $\Omega=1/2$, the found solution corresponds to the weakfield limit of the black strings/branes. The black strings/branes are compact gravitating objects which have the topology (fourdimensional Schwarzschild spacetime)$\times$ ($d$dimensional internal space) with $d\geq 1$. We present the arguments in favour of these objects. First, they satisfy the gravitational tests for the parameterized postNewtonian parameter $\gamma$ at the same level of accuracy as General Relativity. Second, they are preferable from the thermodynamical point of view. Third, averaging over the Universe, they do not destroy the stabilization of the internal space. These are the astrophysical and cosmological aspects of the black strings/branes.
Replacements for Thu, 23 Nov 17
 [53] arXiv:1607.02094 (replaced) [pdf, other]

Title: Magnetooptic effects of the Cosmic Microwave BackgroundAuthors: Damian EjlliComments: Additional references added. More details have been added in the introduction and discussion sections. Slightly reduced version with respect to previous one. Unchanged final resultsSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc); High Energy Physics  Phenomenology (hepph); Quantum Physics (quantph)
 [54] arXiv:1607.05123 (replaced) [pdf, ps, other]

Title: Imprint of thawing scalar fields on large scale galaxy overdensityComments: Revised version with new results, comments welcomeSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
 [55] arXiv:1612.05588 (replaced) [pdf, other]

Title: Collective excitations of a quantized vortex in $^3P_2$ superfluids in neutron starsComments: 12 pages, 6 figuresJournalref: Phys. Rev. C 96, 055807, 2017Subjects: Nuclear Theory (nuclth); High Energy Astrophysical Phenomena (astroph.HE)
 [56] arXiv:1701.05205 (replaced) [pdf, other]

Title: Characterizing Exoplanet HabitabilityAuthors: Tyler D. RobinsonComments: acceptedSubjects: Earth and Planetary Astrophysics (astroph.EP)
 [57] arXiv:1701.07319 (replaced) [pdf, other]

Title: Cold dark energy constraints from the abundance of galaxy clustersAuthors: Caroline Heneka, David Rapetti, Matteo Cataneo, Adam B. Mantz, Steven W. Allen, Anja von der LindenComments: 14 pages, 6 figures, 3 tables. Accepted for publiction in MNRASJournalref: MNRAS 473 (2018) 3882Subjects: Cosmology and Nongalactic Astrophysics (astroph.CO)
 [58] arXiv:1704.02988 (replaced) [pdf, ps, other]

Title: Formation of Globular Cluster Candidates in Merging Protogalaxies at High Redshift: A View from the FIRE Cosmological SimulationsAuthors: Jihoon Kim (1, 2, 3, 4), Xiangcheng Ma (3), Michael Y. Grudić (3), Philip F. Hopkins (3), Christopher C. Hayward (5,6), Andrew Wetzel (3,7,8,9), ClaudeAndré FaucherGiguère (10), Dušan Kereš (11), Shea GarrisonKimmel (3,4), Norman Murray (12,13) ((1) Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, (2) Stanford University, (3) California Institute of Technology, (4) Einstein Fellow, (5) Center for Computational Astrophysics, Flatiron Institute, (6) HarvardSmithsonian Center for Astrophysics, (7) Carnegie Observatories, (8) University of California, Davis, (9) CaltechCarnegie Fellow, (10) Northwestern University, (11) Center for Astrophysics and Space Sciences, University of California, San Diego, (12) Canadian Institute for Theoretical Astrophysics, University of Toronto, (13) Canada Research Chair in Astrophysics)Comments: 14 pages, 14 figures, Accepted for publication in the Monthly Notices of the Royal Astronomical Society, Highresolution version of this article also available at this http URLSubjects: Astrophysics of Galaxies (astroph.GA); Cosmology and Nongalactic Astrophysics (astroph.CO)
 [59] arXiv:1705.03897 (replaced) [pdf, other]

Title: Surprises from Complete Vector Portal Theories: New Insights into the Dark Sector and its Interplay with Higgs PhysicsComments: 5 pages, 3 figures; v2: minor corrections, references added, journal versionJournalref: Phys.Rev. D96 (2017) no.9, 095006Subjects: High Energy Physics  Phenomenology (hepph); Cosmology and Nongalactic Astrophysics (astroph.CO); High Energy Physics  Experiment (hepex); High Energy Physics  Theory (hepth)
 [60] arXiv:1706.00825 (replaced) [pdf, other]

Title: The magnetar model for Type I superluminous supernovae I: Bayesian analysis of the full multicolour light curve sample with MOSFiTAuthors: Matt Nicholl (1), James Guillochon (1), Edo Berger (1) ((1) HarvardSmithsonian Center for Astrophysics)Comments: Accepted in ApJSubjects: High Energy Astrophysical Phenomena (astroph.HE); Cosmology and Nongalactic Astrophysics (astroph.CO); Solar and Stellar Astrophysics (astroph.SR)
 [61] arXiv:1707.00957 (replaced) [pdf, other]

Title: General bounds in Hybrid Natural InflationAuthors: Gabriel German, Alfredo HerreraAguilar, Juan Carlos Hidalgo, Roberto A. Sussman, Jose TapiaComments: 16 pages, 5 figures. A paragraph has been added after Eq. (57). Version accepted for publication in JCAPSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO)
 [62] arXiv:1707.02302 (replaced) [pdf, other]

Title: The KMOS Redshift One Spectroscopic Survey (KROSS): the origin of disk turbulence in z~0.9 starforming galaxiesAuthors: H. L. Johnson (1), C. M. Harrison (2 and 1), A. M. Swinbank (1 and 3), A. L. Tiley (1 and 4), J. P. Stott (5 and 4), R. G. Bower (1 and 3), Ian Smail (1 and 3), A. J. Bunker (4 and 6), D. Sobral (5 and 7), O. J. Turner (8 and 2), P. Best (8), M. Bureau (4), M. Cirasuolo (2), M. J. Jarvis (4 and 9), G. Magdis (10 and 11), R. M. Sharples (1 and 12), J. BlandHawthorn (13), B. Catinella (14), L. Cortese (14), S. M. Croom (13 and 15), C. Federrath (16), K. Glazebrook (17), S. M. Sweet (17), J. J. Bryant (13 and 18), M. Goodwin (18), I. S. Konstantopoulos (18), J. S. Lawrence (18), A. M. Medling (16), M. S. Owers (19 and 18), S. Richards (20) ((1) Durham CEA, (2) ESO, (3) Durham ICC, (4) Oxford, (5) Lancaster, (6) Kavli Institute Japan, (7) Leiden, (8) SUPA, (9) Western Cape, (10) DARK, (11) IfA Athens, (12) Durham CfAI, (13) SIfA, (14) ICRAR, (15) CAASTRO, (16) ANU, (17) Swinburne, (18) AAO, (19) Macquarie, (20) SOFIA)Comments: Accepted for publication in MNRAS. Data available at this http URLSubjects: Astrophysics of Galaxies (astroph.GA)
 [63] arXiv:1707.06827 (replaced) [pdf, other]

Title: Constraining interacting dark energy with CMB and BAO future surveysComments: 15 pages, 10 figures. Replaced to match published versionJournalref: Phys. Rev. D 96, 103529 (2017)Subjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
 [64] arXiv:1707.09373 (replaced) [pdf, ps, other]

Title: The Stellar Mass, Star Formation Rate and Dark Matter Halo Properties of LAEs at $z\sim2$Authors: Haruka Kusakabe, Kazuhiro Shimasaku, Masami Ouchi, Kimihiko Nakajima, Ryosuke Goto, Takuya Hashimoto, Akira Konno, Yuichi Harikane, John D. Silverman, Peter L. CapakComments: 34 pages, 15 figures, 6 tables. Accepted for publication in PASJSubjects: Astrophysics of Galaxies (astroph.GA)
 [65] arXiv:1708.03626 (replaced) [pdf, ps, other]

Title: Solar coronal lines in the visible and infrared. A rough guideComments: Submitted to ApJ  revisedSubjects: Solar and Stellar Astrophysics (astroph.SR)
 [66] arXiv:1708.04154 (replaced) [pdf, other]

Title: Rotationsupported Neutrinodriven Supernova Explosions in Three Dimensions and the Critical Luminosity ConditionAuthors: A. Summa (1), H.Th. Janka (1), T. Melson (1), A. Marek (2) ((1) MPI Astrophysics, Garching, (2) MPCDF, Garching)Comments: 24 pages, 19 figures; refereed version with additional section on resolution dependence; accepted by ApJSubjects: High Energy Astrophysical Phenomena (astroph.HE); Solar and Stellar Astrophysics (astroph.SR)
 [67] arXiv:1708.07254 (replaced) [pdf, ps, other]

Title: Stochastic Electron Acceleration by the Whistler Instability in a Growing Magnetic FieldComments: 7 pages, 6 figures, accepted in The Astrophysical JournalSubjects: High Energy Astrophysical Phenomena (astroph.HE)
 [68] arXiv:1709.03420 (replaced) [pdf, other]

Title: Clustering dark energy and halo abundancesComments: 18 pages and 9 figures, v2: references added and some points clarified, matches the accepted version in JCAPSubjects: Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
 [69] arXiv:1709.09397 (replaced) [pdf, other]

Title: On the existence of steady gap solutions in rotating black hole magnetospheresComments: typos corrected, 5 figures, to appear in PRDSubjects: High Energy Astrophysical Phenomena (astroph.HE)
 [70] arXiv:1710.01763 (replaced) [pdf, other]

Title: Pop III $\textit{i}$process Nucleosynthesis and the Elemental Abundances of SMSS J03136708 and the Most IronPoor StarsComments: Accepted for publication in MNRAS LettersSubjects: Solar and Stellar Astrophysics (astroph.SR)
 [71] arXiv:1710.02507 (replaced) [pdf, other]

Title: Improved bound on isotropic Lorentz violation in the photon sector from extensive air showersComments: 18 pages, v3: final version to appear in PRDSubjects: High Energy Physics  Phenomenology (hepph); High Energy Astrophysical Phenomena (astroph.HE)
 [72] arXiv:1710.07286 (replaced) [pdf, ps, other]

Title: Probing the Hot Xray Corona around the Massive Spiral Galaxy, NGC 6753, Using Deep XMMNewton observationsAuthors: Akos Bogdan, Herve Bourdin, William R. Forman, Ralph P. Kraft, Mark Vogelsberger, Lars Hernquist, Volker SpringelComments: 12 pages, 10 figures, typos corrected, accepted for publication in ApJSubjects: Astrophysics of Galaxies (astroph.GA); High Energy Astrophysical Phenomena (astroph.HE)
 [73] arXiv:1710.07544 (replaced) [pdf, ps, other]

Title: Binary orbits from combined astrometric and spectroscopic dataAuthors: L.B.LucyComments: 9 pages, 3 figures. Typos corrected. Appendix C.1 added. Generalisation for correlated measurement errorsSubjects: Solar and Stellar Astrophysics (astroph.SR); Instrumentation and Methods for Astrophysics (astroph.IM)
 [74] arXiv:1710.10806 (replaced) [pdf, other]

Title: ALFABURST: A commensal search for Fast Radio Bursts with AreciboAuthors: Griffin Foster, Aris Karastergiou, Golnoosh Golpayegani, Mayuresh Surnis, Duncan R. Lorimer, Jayanth Chennamangalam, Maura McLaughlin, Wes Armour, Jeff Cobb, David H. E. MacMahon, Xin Pei, Kaustubh Rajwade, Andrew P. V. Siemion, Dan Werthimer, Chris J. WilliamsComments: 11 pages, 11 figures, accepted to MNRASSubjects: Instrumentation and Methods for Astrophysics (astroph.IM)
 [75] arXiv:1711.00584 (replaced) [pdf, other]

Title: Optical drift effects in general relativityComments: 38 pages, 9 figures. Added new references, corrected typos, expanded Sec. 3.3, 4.2, corrected equations in Sec. 3.5 and AppendixSubjects: General Relativity and Quantum Cosmology (grqc); Cosmology and Nongalactic Astrophysics (astroph.CO)
 [76] arXiv:1711.01833 (replaced) [pdf, ps, other]

Title: Jet activity in the central BH of the Milky Way in 4th and 14th centuries CEAuthors: Olga I. Piskounova (1), Irina V. Tamarkina (2,3) ((1) Lebedev Physics Institute, Moscow, Russia, (2) WisconsinMadison Uni., USA, (3) Hebrew Uni., Jerusalem)Comments: 10 pages, 10 figuresSubjects: History and Philosophy of Physics (physics.histph); Astrophysics of Galaxies (astroph.GA)
 [77] arXiv:1711.03737 (replaced) [pdf, ps, other]

Title: Soft Theorems For ShiftSymmetric CosmologiesComments: 4 pages; citation added in v2Subjects: High Energy Physics  Theory (hepth); Cosmology and Nongalactic Astrophysics (astroph.CO); General Relativity and Quantum Cosmology (grqc)
 [78] arXiv:1711.04169 (replaced) [pdf, other]

Title: 280 GHz Focal Plane Unit Design and Characterization for the SPIDER2 Suborbital PolarimeterAuthors: A.S. Bergman, P.A.R. Ade, S. Akers, M. Amiri, J.A. Austermann, J.A. Beall, D.T. Becker, S.J. Benton, J.J. Bock, J.R. Bond, S.A. Bryan, H.C. Chiang, C.R. Contaldi, R.S Domagalski, O. Doré, S.M. Duff, A.J. Duivenvoorden, H.K. Eriksen, M. Farhang, J.P. Filippini, L.M. Fissel, A.A. Fraisse, K. Freese, M. Galloway, A.E. Gambrel, N.N. Gandilo, K. Ganga, A. Grigorian, R. Gualtieri, J.E. Gudmundsson, M. Halpern, J. Hartley, M. Hasselfield, G. Hilton, W. Holmes, V.V. Hristov, Z. Huang, J. Hubmayr, K.D. Irwin, W.C. Jones, A. Khan, C.L. Kuo, Z.D. Kermish, S. Li, P.V. Mason, K. Megerian, L. Moncelsi, T.A. Morford, J.M. Nagy, C.B. Netterfield, M. Nolta, B. Osherson, I.L. Padilla, B. Racine, A.S. Rahlin, S. Redmond, C. Reintsema, L.J. Romualdez, J.E. Ruhl, M.C. Runyan, T.M. Ruud, J.A. Shariff, E.C. Shaw, et al. (16 additional authors not shown)Subjects: Instrumentation and Methods for Astrophysics (astroph.IM)
 [79] arXiv:1711.04303 (replaced) [pdf, ps, other]

Title: Spinflavor oscillations of ultrahighenergy cosmic neutrinos in interstellar space: The role of neutrino magnetic momentsComments: 18 pages, 4 figures; fixed misprints in Eq. (7)Journalref: PRD 96 (2017) 103017Subjects: High Energy Physics  Phenomenology (hepph); High Energy Astrophysical Phenomena (astroph.HE); High Energy Physics  Experiment (hepex)
 [80] arXiv:1711.04600 (replaced) [pdf, other]

Title: RAiSE III: 3C radio AGN energetics and compositionComments: 21 pages, 16 figures, 3 tables; accepted in MNRASSubjects: Astrophysics of Galaxies (astroph.GA)
 [81] arXiv:1711.06270 (replaced) [pdf, other]

Title: Joint NuSTAR and Chandra analysis of the obscured quasar in IC 2497  Hanny's Voorwerp systemAuthors: Lia F. Sartori, Kevin Schawinski, Michael J. Koss, Claudio Ricci, Ezequiel Treister, Daniel Stern, George Lansbury, W. Peter Maksym, Mislav Balokovic, Poshak Gandhi, William C. Keel, David R. BallantyneComments: 9 pages, 3 figures. Accepted for publication in MNRASSubjects: Astrophysics of Galaxies (astroph.GA); High Energy Astrophysical Phenomena (astroph.HE)
 [82] arXiv:1711.06734 (replaced) [pdf, other]

Title: MWC349A and B Are Not Gravitationally Bound: New EvidenceComments: 5 pages, 2 figures. ApJ acceptedSubjects: Solar and Stellar Astrophysics (astroph.SR)
 [83] arXiv:1711.07372 (replaced) [pdf, other]

Title: Covariance of the galaxy angular power spectrum with the halo modelAuthors: Fabien LacasaComments: 18+17 pages, 3+4 figures. Added a discussion of dilation and tidal effects in SSC. Version submitted to A&ASubjects: Cosmology and Nongalactic Astrophysics (astroph.CO)
 [84] arXiv:1711.07495 (replaced) [pdf, other]

Title: Detection of HC$_5$N and HC$_7$N Isotopologues in TMC1 with the Green Bank TelescopeAuthors: Andrew M. Burkhardt, Eric Herbst, Sergei V. Kalenskii, Michael C. McCarthy, Anthony J. Remijan, Brett A. McGuireComments: 8 pages, 2 figures, 3 tables, accepted to MNRASSubjects: Astrophysics of Galaxies (astroph.GA)
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