RAS_WEB (Page 2,273)

Nowhere to Hide: Radio-faint AGN in the GOODS-N field. II. Multi-wavelength AGN selection techniques and host galaxy properties. (arXiv:2103.08575v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Radcliffe_J/0/1/0/all/0/1">J. F. Radcliffe</a> (1,2,3), <a href="http://arxiv.org/find/astro-ph/1/au:+Barthel_P/0/1/0/all/0/1">P. D. Barthel</a> (2), <a href="http://arxiv.org/find/astro-ph/1/au:+Thomson_A/0/1/0/all/0/1">A. P. Thomson</a> (3), <a href="http://arxiv.org/find/astro-ph/1/au:+Garrett_M/0/1/0/all/0/1">M. A. Garrett</a> (3,4), <a href="http://arxiv.org/find/astro-ph/1/au:+Beswick_R/0/1/0/all/0/1">R. J. Beswick</a> (3), <a href="http://arxiv.org/find/astro-ph/1/au:+Muxlow_T/0/1/0/all/0/1">T. W. B. Muxlow</a> (3) ((1) University of Pretoria, SA, (2) University of Groningen, NL, (3) University of Manchester, UK, (4) University of Leiden, NL) Obtaining a census of active galactic nuclei (AGN) activity across cosmic time is critical to our understanding of galaxy evolution and formation. Many AGN classification techniques are compromised by dust obscuration. However, very longRead More →

Analytic solutions of scalar perturbations induced by scalar perturbations. (arXiv:2008.12300v2 [gr-qc] UPDATED) <a href="http://arxiv.org/find/gr-qc/1/au:+Inomata_K/0/1/0/all/0/1">Keisuke Inomata</a> We study scalar perturbations induced by scalar perturbations through the non-linear interaction appearing at second order in perturbations. We derive analytic solutions of the induced scalar perturbations in a perfect fluid. In particular, we consider the perturbations in a radiation-dominated era and a matter-dominated era. With the analytic solutions, we also discuss the power spectra of the induced perturbations. We study scalar perturbations induced by scalar perturbations through the non-linear interaction appearing at second order in perturbations. We derive analytic solutions of the induced scalar perturbations in a perfect fluid.Read More →

The spatially-resolved gas and dust connection in neutral inflows and outflows in nearby AGN. (arXiv:2103.08502v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Rupke_D/0/1/0/all/0/1">David S. N. Rupke</a> (1 and 2), <a href="http://arxiv.org/find/astro-ph/1/au:+Thomas_A/0/1/0/all/0/1">Adam D. Thomas</a> (2), <a href="http://arxiv.org/find/astro-ph/1/au:+Dopita_M/0/1/0/all/0/1">Michael A. Dopita</a> (2) ((1) Rhodes College, (2) Australian National University) Dusty, neutral outflows and inflows are a common feature of nearby star-forming galaxies. We characterize these flows in eight galaxies — mostly AGN — selected for their widespread NaI D signatures from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). This survey employs deep, wide field-of-view integral field spectroscopy at moderate spectral resolution (R=7000 at NaI D). We significantly expand the sample ofRead More →

Broadband stability of the Habitable Zone Planet Finder Fabry-P'{e}rot etalon calibration system: evidence for chromatic variation. (arXiv:2103.08456v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Terrien_R/0/1/0/all/0/1">Ryan C Terrien</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ninan_J/0/1/0/all/0/1">Joe P Ninan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Diddams_S/0/1/0/all/0/1">Scott A Diddams</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mahadevan_S/0/1/0/all/0/1">Suvrath Mahadevan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Halverson_S/0/1/0/all/0/1">Samuel Halverson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bender_C/0/1/0/all/0/1">Chad Bender</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fredrick_C/0/1/0/all/0/1">Connor Fredrick</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hearty_F/0/1/0/all/0/1">Fred Hearty</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jennings_J/0/1/0/all/0/1">Jeff Jennings</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Metcalf_A/0/1/0/all/0/1">Andrew J. Metcalf</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Monson_A/0/1/0/all/0/1">Andrew Monson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Roy_A/0/1/0/all/0/1">Arpita Roy</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schwab_C/0/1/0/all/0/1">Christian Schwab</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Stefansson_G/0/1/0/all/0/1">Gudmundur Stefansson</a> The comb-like spectrum of a white light-illuminated Fabry-P'{e}rot etalon can serve as a cost-effective and stable reference for precise Doppler measurements. Understanding the stability of these devices across their broad (100’s of nm) spectral bandwidths is essential to realize their fullRead More →

HD142527: Quantitative disk polarimetry with SPHERE. (arXiv:2103.08462v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Hunziker_S/0/1/0/all/0/1">S. Hunziker</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schmid_H/0/1/0/all/0/1">H. M. Schmid</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ma_J/0/1/0/all/0/1">J. Ma</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:+Avenhaus_H/0/1/0/all/0/1">H. Avenhaus</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boccaletti_A/0/1/0/all/0/1">A. Boccaletti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Beuzit_J/0/1/0/all/0/1">J. L. Beuzit</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chauvin_G/0/1/0/all/0/1">G. Chauvin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dohlen_K/0/1/0/all/0/1">K. Dohlen</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:+Engler_N/0/1/0/all/0/1">N. Engler</a>, <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:+Gratton_R/0/1/0/all/0/1">R. Gratton</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Henning_T/0/1/0/all/0/1">T. Henning</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Langlois_M/0/1/0/all/0/1">M. Langlois</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Milli_J/0/1/0/all/0/1">J. Milli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mouillet_D/0/1/0/all/0/1">D. Mouillet</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tschudi_C/0/1/0/all/0/1">C. Tschudi</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:+Vigan_A/0/1/0/all/0/1">A. Vigan</a> We present high-precision photometry and polarimetry for the protoplanetary disk around HD142527, with a focus on determining the light scattering parameters of the dust. We re-reduced polarimetric differential imaging data of HD142527 inRead More →

Expanded atmospheres and winds in Type I X-ray bursts from accreting neutron stars. (arXiv:2103.08476v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Guichandut_S/0/1/0/all/0/1">Simon Guichandut</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Cumming_A/0/1/0/all/0/1">Andrew Cumming</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Falanga_M/0/1/0/all/0/1">Maurizio Falanga</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Li_Z/0/1/0/all/0/1">Zhaosheng Li</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zamfir_M/0/1/0/all/0/1">Michael Zamfir</a> We calculate steady-state models of radiation-driven super-Eddington winds and static expanded envelopes of neutron stars caused by high luminosities in type I X-ray bursts. We use flux-limited diffusion to model the transition from optically thick to optically thin, and include effects of general relativity, allowing us to study the photospheric radius close to the star as the hydrostatic atmosphere evolves into a wind. We find that the photospheric radius evolves monotonically from static envelopes ($r_{rmRead More →

Reconstruction of Baryon Fraction in Intergalactic Medium through Dispersion Measurements of Fast Radio Bursts. (arXiv:2103.08479v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Dai_J/0/1/0/all/0/1">Ji-Ping Dai</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Xia_J/0/1/0/all/0/1">Jun-Qing Xia</a> Fast radio bursts (FRBs) probe the total column density of free electrons in the intergalactic medium (IGM) along the path of propagation though the dispersion measures (DMs) which depend on the baryon mass fraction in the IGM, i.e., $f_{rm IGM}$. In this letter, we investigate the large-scale clustering information of DMs to study the evolution of $f_{rm IGM}$. When combining with the Planck 2018 measurements, we could give tight constraints on the evolution of $f_{rm IGM}(z)$ from about $10^4$ FRBs with the intrinsicRead More →

Ariel Planetary Interiors White Paper. (arXiv:2103.08481v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Helled_R/0/1/0/all/0/1">Ravit Helled</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Werner_S/0/1/0/all/0/1">Stephanie Werner</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dorn_C/0/1/0/all/0/1">Caroline Dorn</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Guillot_T/0/1/0/all/0/1">Tristan Guillot</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ikoma_M/0/1/0/all/0/1">Masahiro Ikoma</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ito_Y/0/1/0/all/0/1">Yuichi Ito</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kama_M/0/1/0/all/0/1">Mihkel Kama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lichtenberg_T/0/1/0/all/0/1">Tim Lichtenberg</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Miguel_Y/0/1/0/all/0/1">Yamila Miguel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shorttle_O/0/1/0/all/0/1">Oliver Shorttle</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tackley_P/0/1/0/all/0/1">Paul J. Tackley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Valencia_D/0/1/0/all/0/1">Diana Valencia</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vazan_A/0/1/0/all/0/1">Allona Vazan</a> The recently adopted Ariel ESA mission will measure the atmospheric composition of a large number of exoplanets. This information will then be used to better constrain planetary bulk compositions. While the connection between the composition of a planetary atmosphere and the bulk interior is still being investigated, the combination of the atmospheric composition with the measured mass andRead More →

Appearance vs Disappearance of broad absorption line troughs in quasars. (arXiv:2103.08499v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Mishra_S/0/1/0/all/0/1">Sapna Mishra</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vivek_M/0/1/0/all/0/1">M. Vivek</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chand_H/0/1/0/all/0/1">Hum Chand</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Joshi_R/0/1/0/all/0/1">Ravi Joshi</a> We present a new set of 84 Broad absorption line (BAL) quasars ( 1.7 $<$ zem $<$ 4.4) exhibiting an appearance of civ BAL troughs over 0.3$-$4.8 rest-frame years by comparing the Sloan Digital Sky Survey Data Release (SDSSDR)-7, SDSSDR-12, and SDSSDR-14 quasar catalogs. We contrast the nature of BAL variability in this appearing BAL quasar sample with a disappearing BAL quasar sample studied in literature by comparing the quasar’s intrinsic, BAL trough, and continuum parameters between the two samples. WeRead More →

Constraints on the abundance of primordial black holes with different mass distributions from lensing of fast radio bursts. (arXiv:2103.08510v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Zhou_H/0/1/0/all/0/1">Huan Zhou</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Li_Z/0/1/0/all/0/1">Zhengxiang Li</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gao_H/0/1/0/all/0/1">He Gao</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huang_Z/0/1/0/all/0/1">Zhiqi Huang</a> The possibility that primordial black holes (PBHs) form a part of dark matter has been considered for a long time but poorly constrained in the $1-100~M_{odot}$ (or stellar mass range). However, a renewed special interest of PBHs in this mass window was triggered by the discovery at LIGO of the merger events of black-hole binaries. Fast radio bursts (FRBs) are bright radio transients with millisecond duration and high all-sky occurrence rate. Lensing effectRead More →

Classical Physics and Hamiltonian Quantum Mechanics as Relics of the Big Bang. (arXiv:2103.08574v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Hartle_J/0/1/0/all/0/1">James B. Hartle</a> In a fundamental formulation of the quantum mechanics of a closed system such as the universe as a whole, three forms of information are needed to make predictions for the probabilities of alternative time histories of the closed system . These are the action functional of the elementary particles, the quantum istate of the universe, and the description of our specific history. We discuss the origin of the “quasiclassical realm” of familiar experience and Hamiltonian quantum mechanics with its preferred time in such a formulation of quantumRead More →

The C$^{18}$O core mass function toward Orion A: Single-dish observations. (arXiv:2103.08526v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Takemura_H/0/1/0/all/0/1">Hideaki Takemura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nakamura_F/0/1/0/all/0/1">Fumitaka Nakamura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ishii_S/0/1/0/all/0/1">Shun Ishii</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shimajiri_Y/0/1/0/all/0/1">Yoshito Shimajiri</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sanhueza_P/0/1/0/all/0/1">Patricio Sanhueza</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tsukagoshi_T/0/1/0/all/0/1">Takashi Tsukagoshi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kawabe_R/0/1/0/all/0/1">Ryohei Kawabe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hirota_T/0/1/0/all/0/1">Tomoya Hirota</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kataoka_A/0/1/0/all/0/1">Akimasa Kataoka</a> We have performed an unbiased dense core survey toward the Orion A Giant Molecular Cloud in the C$^{18}$O ($J$=1–0) emission line taken with the Nobeyama Radio Observatory (NRO) 45-m telescope. The effective angular resolution of the map is 26″, which corresponds to $sim$ 0.05 pc at a distance of 414 pc. By using the Herschel-Planck H$_2$ column density map, we calculate the C$^{18}$O fractional abundance andRead More →

The Core Mass Function in the Orion Nebula Cluster Region: What Determines the Final Stellar Masses?. (arXiv:2103.08527v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Takemura_H/0/1/0/all/0/1">Hideaki Takemura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nakamura_F/0/1/0/all/0/1">Fumitaka Nakamura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kong_S/0/1/0/all/0/1">Shuo Kong</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Arce_H/0/1/0/all/0/1">H&#xe9;ctor G. Arce</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Carpenter_J/0/1/0/all/0/1">John M. Carpenter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ossenkopf_Okada_V/0/1/0/all/0/1">Volker Ossenkopf-Okada</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Klessen_R/0/1/0/all/0/1">Ralf Klessen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sanhueza_P/0/1/0/all/0/1">Patricio Sanhueza</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shimajiri_Y/0/1/0/all/0/1">Yoshito Shimajiri</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tsukagoshi_T/0/1/0/all/0/1">Takashi Tsukagoshi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kawabe_R/0/1/0/all/0/1">Ryohei Kawabe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ishii_S/0/1/0/all/0/1">Shun Ishii</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dobashi_K/0/1/0/all/0/1">Kazuhito Dobashi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shimoikura_T/0/1/0/all/0/1">Tomomi Shimoikura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Goldsmith_P/0/1/0/all/0/1">Paul F. Goldsmith</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sanchez_Monge_A/0/1/0/all/0/1">&#xc1;lvaro S&#xe1;nchez-Monge</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kauffmann_J/0/1/0/all/0/1">Jens Kauffmann</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pillai_T/0/1/0/all/0/1">Thushara Pillai</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Padoan_P/0/1/0/all/0/1">Paolo Padoan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ginsberg_A/0/1/0/all/0/1">Adam Ginsberg</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Smith_R/0/1/0/all/0/1">Rowan J. Smith</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bally_J/0/1/0/all/0/1">John Bally</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mairs_S/0/1/0/all/0/1">Steve Mairs</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pineda_J/0/1/0/all/0/1">Jaime E. Pineda</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lis_D/0/1/0/all/0/1">Dariusz C. Lis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burkhart_B/0/1/0/all/0/1">Blakesley Burkhart</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schilke_P/0/1/0/all/0/1">Peter Schilke</a>,Read More →

Resolving Complex Inner X-ray Structure of the Gravitationaly Lensed AGN MGB2016+112. (arXiv:2103.08537v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Schwartz_D/0/1/0/all/0/1">Daniel Schwartz</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Spingola_C/0/1/0/all/0/1">Cristiana Spingola</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Barnacka_A/0/1/0/all/0/1">Anna Barnacka</a> We use a Chandra X-ray observation of the gravitationally lensed system MGB2016+112 at z=3.273 to elucidate presence of at least two X-ray sources. We find that these sources are consistent with the VLBI components measured by citet{Spingola19}, which are separated by $sim 200$ pc. Their intrinsic 0.5 — 7 keV source frame luminosities are 2.6$times$10$^{43}$ and 4.2$times$10$^{44}$ erg s$^{-1}$. Most likely this system contains a dual active galactic nucleus (AGN), but we possibly are detecting an AGN plus a pc-scale X-ray jet, theRead More →

Graviton Self-Energy from Gravitons in Cosmology. (arXiv:2103.08547v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Tan_L/0/1/0/all/0/1">L. Tan</a> (Florida), <a href="http://arxiv.org/find/gr-qc/1/au:+Tsamis_N/0/1/0/all/0/1">N. C. Tsamis</a> (Crete), <a href="http://arxiv.org/find/gr-qc/1/au:+Woodard_R/0/1/0/all/0/1">R. P. Woodard</a> (Florida) Although matter contributions to the graviton self-energy $-i[mbox{}^{munu} Sigma^{rhosigma}](x;x’)$ must be separately conserved on $x^{mu}$ and ${x’}^{mu}$, graviton contributions obey the weaker constraint of the Ward identity, which involves a divergence on both coordinates. On a general homogeneous and isotropic background this leads to just four structures functions for matter contributions but nine structure functions for graviton contributions. We propose a convenient parameterization for these nine structure functions. We also apply the formalism to explicit one loop computations of $-i[mbox{}^{munu} Sigma^{rhosigma}](x;x’)$ on deRead More →

A Robust Model for Flux Density Calculations of Radio Halos in Galaxy Clusters: Halo-FDCA. (arXiv:2103.08554v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Boxelaar_J/0/1/0/all/0/1">J.M. Boxelaar</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Weeren_R/0/1/0/all/0/1">R.J. van Weeren</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Botteon_A/0/1/0/all/0/1">A. Botteon</a> Here we present Halo-FDCA, a robust open source Python package for modeling and estimating total flux densities of radio (mini) halos in galaxy clusters. Radio halos are extended ( ~200 – 1500 kpc in size) synchrotron emitting sources found in galaxy clusters that trace the presence of cosmic rays and magnetic fields in the intracluster medium (ICM). These sources are centrally located and have a low surface brightness. Their exact origin is still unknown but they are likely relatedRead More →

Statistical recovery of the BAO scale from multipoles of the beam-convolved 21cm correlation function. (arXiv:2103.08568v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Kennedy_F/0/1/0/all/0/1">Fraser Kennedy</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bull_P/0/1/0/all/0/1">Philip Bull</a> Despite being designed as an interferometer, the MeerKAT radio array (an SKA pathfinder) can also be used in autocorrelation (`single-dish’) mode, where each dish scans the sky independently. Operating in this mode allows extremely high survey speeds to be achieved, albeit at significantly lower angular resolution. We investigate the recovery of the baryon acoustic oscillation (BAO) scale from multipoles of the redshift-space correlation function as measured by a low angular resolution 21cm intensity mapping survey of this kind. Our approach is to constructRead More →

A Model for Fast Blue Optical Transient AT2018Cow: Circumstellar Interaction of a Pulsational Pair-instability Supernova. (arXiv:2008.11404v2 [astro-ph.HE] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Leung_S/0/1/0/all/0/1">Shing-Chi Leung</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Blinnikov_S/0/1/0/all/0/1">Sergei Blinnikov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nomoto_K/0/1/0/all/0/1">Ken&#x27;ichi Nomoto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Baklanov_P/0/1/0/all/0/1">Petr Baklanov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sorokina_E/0/1/0/all/0/1">Elena Sorokina</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tolstov_A/0/1/0/all/0/1">Alexey Tolstov</a> The Fast Blue Optical Transient (FBOT) ATLAS18qqn (AT2018cow) has a light curve as bright as superluminous supernovae but rises and falls much faster. We model this light curve by circumstellar interaction of a pulsational pair-instability (PPI) supernova (SN) model based on our PPISN models studied in previous work. We focus on the 42 $M_odot$ He star (core of a 80 $M_{odot}$ star) which has circumstellar matter of mass 0.50Read More →

Analytic formula for the dynamics around inflation end and implications on primordial gravitational waves. (arXiv:2009.03611v2 [astro-ph.CO] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Ito_A/0/1/0/all/0/1">Asuka Ito</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Soda_J/0/1/0/all/0/1">Jiro Soda</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yamaguchi_M/0/1/0/all/0/1">Masahide Yamaguchi</a> We argue that primordial gravitational waves have a spectral break and its information is quite useful for exploring the early universe. Indeed, such a spectral break can be a fingerprint of the end of inflation, and the amplitude and the frequency at the break can tell us the energy scale of inflation and the reheating temperature simultaneously. In order to investigate the spectral break, we give an analytic formula for evolution of the Hubble parameter around the end ofRead More →

The formation of the Milky Way halo and its dwarf satellites: a NLTE-1D abundance analysis. IV. Segue 1, Triangulum II, and Coma Berenices UFDs. (arXiv:2103.08435v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Sitnova_T/0/1/0/all/0/1">T. M. Sitnova</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mashonkina_L/0/1/0/all/0/1">L. I. Mashonkina</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tatarnikov_A/0/1/0/all/0/1">A. M. Tatarnikov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Voziakova_O/0/1/0/all/0/1">O. V. Voziakova</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burlak_M/0/1/0/all/0/1">M. A. Burlak</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pakhomov_Y/0/1/0/all/0/1">Yu. V. Pakhomov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jablonka_P/0/1/0/all/0/1">P. Jablonka</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Neretina_M/0/1/0/all/0/1">M. D. Neretina</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Frebel_A/0/1/0/all/0/1">A. Frebel</a> We present atmospheric parameters and abundances for chemical elements from carbon to barium in metal-poor stars in Segue 1 (seven stars), Coma Berenices (three stars), and Triangulum II (one star) ultra-faint dwarf galaxies (UFDs). The effective temperatures rely on new photometric observations in the visibleRead More →