RAS_WEB (Page 2,337)

HD 76920b pinned down: a detailed analysis of the most eccentric planetary system around an evolved star. (arXiv:2102.08902v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Bergmann_C/0/1/0/all/0/1">C. Bergmann</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jones_M/0/1/0/all/0/1">M. I. Jones</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zhao_J/0/1/0/all/0/1">J. Zhao</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Brahm_R/0/1/0/all/0/1">R. Brahm</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Torres_P/0/1/0/all/0/1">P. Torres</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wittenmyer_R/0/1/0/all/0/1">R. A. Wittenmyer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gunn_F/0/1/0/all/0/1">F. Gunn</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pollard_K/0/1/0/all/0/1">K. R. Pollard</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zapata_A/0/1/0/all/0/1">A. Zapata</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vanzi_L/0/1/0/all/0/1">L. Vanzi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_S/0/1/0/all/0/1">S. Wang</a> We present 63 new multi-site radial velocity measurements of the K1III giant HD 76920, which was recently reported to host the most eccentric planet known to orbit an evolved star. We focussed our observational efforts on the time around the predicted periastron passage and achieved near-continuous phase coverage of theRead More →

Extension of the Advanced Spectral Leakage scheme for neutron star merger simulations. (arXiv:2102.08882v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Gizzi_D/0/1/0/all/0/1">Davide Gizzi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lundman_C/0/1/0/all/0/1">Christoffer Lundman</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+OConnor_E/0/1/0/all/0/1">Evan O&#x27;Connor</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rosswog_S/0/1/0/all/0/1">Stephan Rosswog</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Perego_A/0/1/0/all/0/1">Albino Perego</a> We extend a neutrino transport approximation, called Advanced Spectral Leakage (ASL), with the purpose of modeling neutrino-driven winds in neutron star mergers. Based on a number of snapshots we gauge the ASL parameters by comparing against both the two-moment (M1) scheme implemented in the FLASH code and the Monte Carlo neutrino code Sedonu. The ASL scheme contains three parameters, the least robust of which results to be a blocking parameter for electron neutrinos and anti-neutrinos. TheRead More →

The Case for Thermalization as a Contributor to the [CII] Deficit. (arXiv:2102.08865v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Sutter_J/0/1/0/all/0/1">Jessica Sutter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dale_D/0/1/0/all/0/1">Daniel A. Dale</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sandstrom_K/0/1/0/all/0/1">Karin Sandstrom</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Smith_J/0/1/0/all/0/1">J.D.T. Smith</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bolatto_A/0/1/0/all/0/1">Alberto Bolatto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boquien_M/0/1/0/all/0/1">Mederic Boquien</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Calzetti_D/0/1/0/all/0/1">Daniela Calzetti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Croxall_K/0/1/0/all/0/1">Kevin V. Croxall</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Looze_I/0/1/0/all/0/1">Ilse De Looze</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Galametz_M/0/1/0/all/0/1">Maude Galametz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Groves_B/0/1/0/all/0/1">Brent A. Groves</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Helou_G/0/1/0/all/0/1">George Helou</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Herrera_Camus_R/0/1/0/all/0/1">Rodrigo Herrera-Camus</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hunt_L/0/1/0/all/0/1">Leslie K. Hunt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kennicutt_R/0/1/0/all/0/1">Robert C. Kennicutt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pelligrini_E/0/1/0/all/0/1">Eric W. Pelligrini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wilson_C/0/1/0/all/0/1">Christine Wilson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wolfire_M/0/1/0/all/0/1">Mark G. Wolfire</a> The [CII] deficit, which describes the observed decrease in the ratio of [CII] 158 micron emission to continuum infrared emission in galaxies with high star formation surface densities, places aRead More →

Constraining Light Dark Photons from GW190517 and GW190426_152155. (arXiv:2102.08857v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Ghosh_D/0/1/0/all/0/1">Diptimoy Ghosh</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sachdeva_D/0/1/0/all/0/1">Divya Sachdeva</a> Ultralight dark photons predicted in several Standard Model extensions can trigger the superradiant instability around rotating black holes if their Compton wavelength is comparable to the Blackhole radius. Consequently, the angular momentum of the black hole is reduced to a value which depends upon the mass and spin of the black hole as well as the mass of the dark photon. We use the mass and spin measurements of the primary black holes in two recently observed binary black hole systems: GW190517 and GW190426_152155 to constrain dark photon massRead More →

Detectability of continuous gravitational waves from isolated neutron stars in the Milky Way: the population synthesis approach. (arXiv:2102.08854v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Cieslar_M/0/1/0/all/0/1">Marek Cie&#x15b;lar</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Bulik_T/0/1/0/all/0/1">Tomasz Bulik</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Curylo_M/0/1/0/all/0/1">Ma&#x142;gorzata Cury&#x142;o</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Sieniawska_M/0/1/0/all/0/1">Magdalena Sieniawska</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Singh_N/0/1/0/all/0/1">Neha Singh</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Bejger_M/0/1/0/all/0/1">Micha&#x142; Bejger</a> Aims. We estimate the number of pulsars, detectable as continuous gravitational wave sources with the current and future gravitational-wave detectors, assuming a simple phenomenological model of evolving non-axisymmetry of the rotating neutron star. Methods. We employ a numerical model of the Galactic neutron star population, with the properties established by comparison with radio observations of isolated Galactic pulsars. We generate an arbitrarily large synthetic population of neutron starsRead More →

The intermediate neutron capture process. I. Development of the i-process in low-metallicity low-mass AGB stars. (arXiv:2102.08840v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Choplin_A/0/1/0/all/0/1">A. Choplin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Siess_L/0/1/0/all/0/1">L. Siess</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Goriely_S/0/1/0/all/0/1">S. Goriely</a> Gathering observations report a growing number of metal-poor stars showing an abundance pattern midway between the s- and r-processes. These so called r/s-stars raise the need for an intermediate neutron capture process (i-process), which is thought to result from the ingestion of protons in a convective helium-burning region, but whose astrophysical site is still largely debated. We investigate whether an i-process during the asymptotic giant branch (AGB) phase of low-metallicity low-mass stars can develop and whether it can explainRead More →

Geomorphological Analysis Using Unpiloted Aircraft Systems, Structure from Motion, and Deep Learning. (arXiv:1909.12874v5 [cs.RO] UPDATED) <a href="http://arxiv.org/find/cs/1/au:+Chen_Z/0/1/0/all/0/1">Zhiang Chen</a>, <a href="http://arxiv.org/find/cs/1/au:+Scott_T/0/1/0/all/0/1">Tyler R. Scott</a>, <a href="http://arxiv.org/find/cs/1/au:+Bearman_S/0/1/0/all/0/1">Sarah Bearman</a>, <a href="http://arxiv.org/find/cs/1/au:+Anand_H/0/1/0/all/0/1">Harish Anand</a>, <a href="http://arxiv.org/find/cs/1/au:+Keating_D/0/1/0/all/0/1">Devin Keating</a>, <a href="http://arxiv.org/find/cs/1/au:+Scott_C/0/1/0/all/0/1">Chelsea Scott</a>, <a href="http://arxiv.org/find/cs/1/au:+Arrowsmith_J/0/1/0/all/0/1">J Ramon Arrowsmith</a>, <a href="http://arxiv.org/find/cs/1/au:+Das_J/0/1/0/all/0/1">Jnaneshwar Das</a> We present a pipeline for geomorphological analysis that uses structure from motion (SfM) and deep learning on close-range aerial imagery to estimate spatial distributions of rock traits (size, roundness, and orientation) along a tectonic fault scarp. The properties of the rocks on the fault scarp derive from the combination of initial volcanic fracturing and subsequent tectonic and geomorphic fracturing, and our pipeline allows scientistsRead More →

Higher Compact Multiple Occurrence Around Metal-Poor M-Dwarfs and Late K-Dwarfs. (arXiv:2102.08839v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Anderson_S/0/1/0/all/0/1">Sophie G. Anderson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dittmann_J/0/1/0/all/0/1">Jason A. Dittmann</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ballard_S/0/1/0/all/0/1">Sarah Ballard</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bedell_M/0/1/0/all/0/1">Megan Bedell</a> The planet-metallicity correlation serves as a potential link between exoplanet systems as we observe them today and the effects of bulk composition on the planet formation process. Many observers have noted a tendency for Jovian planets to form around stars with higher metallicities; however, there is no consensus on a trend for smaller planets. Here, we investigate the planet-metallicity correlation for rocky planets in single and multi-planet systems around Kepler M-dwarf and late K-dwarf stars. Due to molecular blanketingRead More →

Comparative high-resolution spectroscopy of M dwarfs — exploring non-LTE effects. (arXiv:2102.08836v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Olander_T/0/1/0/all/0/1">T. Olander</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Heiter_U/0/1/0/all/0/1">U. Heiter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kochukhov_O/0/1/0/all/0/1">O. Kochukhov</a> M dwarfs are key targets for high-resolution spectroscopic analyses due to a high incidence of these stars in the solar neighbourhood and their importance as exoplanetary hosts. Several methodological challenges make such analyses difficult, leading to significant discrepancies in the published results. We compare M dwarf parameters derived by recent high-resolution near-infrared studies with each other and with fundamental stellar parameters. We also assess to what extent deviations from local thermodynamic equilibrium (LTE) for Fe and K influence the outcome of these studies. WeRead More →

MOND-like behavior in the Dirac-Milne universe — Flat rotation curves and mass/velocity relations in galaxies and clusters. (arXiv:2102.08834v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Chardin_G/0/1/0/all/0/1">Gabriel Chardin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dubois_Y/0/1/0/all/0/1">Yohan Dubois</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Manfredi_G/0/1/0/all/0/1">Giovanni Manfredi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Miller_B/0/1/0/all/0/1">Bruce Miller</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Stahl_C/0/1/0/all/0/1">Cl&#xe9;ment Stahl</a> We show that in the Dirac-Milne universe (a matter-antimatter symmetric universe where the two components repel each other), rotation curves are generically flat beyond the characteristic distance of about 3 virial radii, and that a Tully-Fisher relation with exponent $approx 3$ is satisfied. Using 3D simulations with a modified version of the RAMSES code, we show that the Dirac-Milne cosmology presents a Faber-Jackson relation with a very small scatter and anRead More →

Radio and optical observations of the possible AE Aqr twin, LAMOST J024048.51+195226.9. (arXiv:2102.08800v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Pretorius_M/0/1/0/all/0/1">M. L. Pretorius</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hewitt_D/0/1/0/all/0/1">D. M. Hewitt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Woudt_P/0/1/0/all/0/1">P. A. Woudt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fender_R/0/1/0/all/0/1">R. P. Fender</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Heywood_I/0/1/0/all/0/1">I. Heywood</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Knigge_C/0/1/0/all/0/1">C. Knigge</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Miller_Jones_J/0/1/0/all/0/1">J. C. A. Miller-Jones</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Buckley_D/0/1/0/all/0/1">D. A. H. Buckley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Worters_H/0/1/0/all/0/1">H. L. Worters</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Potter_S/0/1/0/all/0/1">S. B. Potter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Williams_D/0/1/0/all/0/1">D. R. A. Williams</a> Thorstensen (2020) recently argued that the cataclysmic variable (CV) LAMOST J024048.51+195226.9 may be a twin to the unique magnetic propeller system AE Aqr. If this is the case, two predictions are that it should display a short period white dwarf spin modulation, and that it shouldRead More →

Massive $Delta$-resonance admixed hypernuclear stars with anti-kaon condensations. (arXiv:2102.08787v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Thapa_V/0/1/0/all/0/1">Vivek Baruah Thapa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sinha_M/0/1/0/all/0/1">Monika Sinha</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Li_J/0/1/0/all/0/1">Jia Jie Li</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sedrakian_A/0/1/0/all/0/1">Armen Sedrakian</a> In this work, we study the effect of (anti)kaon condensation on the properties of compact stars that develop hypernuclear cores with and without an admixture of $Delta$-resonances. We work within the covariant density functional theory with the parameters adjusted to $K$-atomic and kaon-nucleon scattering data in the kaonic sector. The density-dependent parameters in the hyperonic sector are adjusted to the data on $Lambda$ and $Xi^-$ hypernuclei data. The $Delta$-resonance couplings are tuned to the data obtained from their scattering off nucleiRead More →

Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): Late infall causing disk misalignment and dynamic structures in SU Aur. (arXiv:2102.08781v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Ginski_C/0/1/0/all/0/1">C. Ginski</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Facchini_S/0/1/0/all/0/1">S. Facchini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huang_J/0/1/0/all/0/1">J. Huang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Benisty_M/0/1/0/all/0/1">M. Benisty</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vaendel_D/0/1/0/all/0/1">D. Vaendel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Stapper_L/0/1/0/all/0/1">L. Stapper</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dominik_C/0/1/0/all/0/1">C. Dominik</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bae_J/0/1/0/all/0/1">J. Bae</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Menard_F/0/1/0/all/0/1">F. Menard</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Muro_Arena_G/0/1/0/all/0/1">G. Muro-Arena</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hogerheijde_M/0/1/0/all/0/1">M. Hogerheijde</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+McClure_M/0/1/0/all/0/1">M. McClure</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Holstein_R/0/1/0/all/0/1">R. G. van Holstein</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Birnstiel_T/0/1/0/all/0/1">T. Birnstiel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boehler_Y/0/1/0/all/0/1">Y. Boehler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bohn_A/0/1/0/all/0/1">A. Bohn</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Flock_M/0/1/0/all/0/1">M. Flock</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mamajek_E/0/1/0/all/0/1">E. E. Mamajek</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Manara_C/0/1/0/all/0/1">C. F. Manara</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pinilla_P/0/1/0/all/0/1">P. Pinilla</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pinte_C/0/1/0/all/0/1">C. Pinte</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ribas_A/0/1/0/all/0/1">A. Ribas</a> Gas-rich circumstellar disks are the cradles of planet formation. As such, theirRead More →

Comparison of solar wind speed estimates from nearly simultaneous IPS observations at 327 and 111 MHz. (arXiv:2102.08767v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Chashei_I/0/1/0/all/0/1">I.V. Chashei</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lukmanov_V/0/1/0/all/0/1">V.R. Lukmanov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tyulbashev_S/0/1/0/all/0/1">S.A. Tyulbashev</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tokumaru_M/0/1/0/all/0/1">M. Tokumaru</a> Results are presented of a comparison between solar wind speed estimates made using the time delays between 3 pairs of 327 MHz antennas at ISEE and estimates made by modeling the temporal power spectra observed with the 111 MHz BSA antenna at LPI. The observations were made for 6 years in the descending phase of solar cycle 24. More than 100 individual records were obtained for the compact source 3C48 and the extended and anisotropicRead More →

Analyzing supergranular power spectra using helioseismic normal-mode coupling. (arXiv:2102.08715v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Hanson_C/0/1/0/all/0/1">Chris S. Hanson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hanasoge_S/0/1/0/all/0/1">Shravan Hanasoge</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sreenivasan_K/0/1/0/all/0/1">Katepalli R. Sreenivasan</a> Normal-mode coupling is a technique applied to probe the solar interior using surface observations of oscillations. The technique, which is straightforward to implement, makes more use of the seismic information in the wavefield than other comparable local imaging techniques and therefore has the potential to significantly improve current capabilities. Here, we examine supergranulation power spectra using mode-coupling analyses of intermediate-to-high-degree modes by invoking a Cartesian-geometric description of wave propagation under the assumption that the localized patches are much smaller in size than the solarRead More →

Metastable strings and dumbbells in supersymmetric hybrid inflation. (arXiv:2102.08923v1 [hep-ph]) <a href="http://arxiv.org/find/hep-ph/1/au:+Buchmuller_W/0/1/0/all/0/1">Wilfried Buchmuller</a> We study symmetry breaking and topological defects in a supersymmetric model with gauge group $text{U}(2)$, which can be identified with the right-handed part $text{SU}(2)_R times text{U}(1)_{B-L}$ of an extended electroweak symmetry of the Standard Model. The model has two phases of hybrid inflation terminated by tachyonic preheating where either monopoles and strings or, alternatively, dumbbells are formed. In the first case a stochastic gravitational wave background is predicted in the LIGO-Virgo band, possibly extending to the LISA frequency band and to nanohertz frequencies, which is generated by a metastable cosmic string network.Read More →