August 2021

Ab initio based equation of state of dense water for planetary and exoplanetary modeling. (arXiv:1810.05658v2 [astro-ph.EP] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Mazevet_S/0/1/0/all/0/1">S. Mazevet</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Licari_A/0/1/0/all/0/1">A. Licari</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chabrier_G/0/1/0/all/0/1">G. Chabrier</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Potekhin_A/0/1/0/all/0/1">A. Y. Potekhin</a> As a first step toward a multi-phase equation of state for dense water, we develop a temperature-dependent equation of state for dense water covering the liquid and plasma regimes and extending to the super-ionic and gas regimes. This equation of state covers the complete range of conditions encountered in planetary modeling. We use first principles quantum molecular dynamics simulations and its Thomas-Fermi extension to reach the highest pressures encountered in giant planets several times theRead More →

Using Secondary Tau Neutrinos to Probe Heavy Dark Matter Decays in Earth. (arXiv:2108.13412v1 [hep-ph]) <a href="http://arxiv.org/find/hep-ph/1/au:+Saveliev_M/0/1/0/all/0/1">Matthew Saveliev</a>, <a href="http://arxiv.org/find/hep-ph/1/au:+Hyde_J/0/1/0/all/0/1">Jeffrey Hyde</a> Dark matter particles can be gravitationally trapped by celestial bodies, motivating searches for localized annihilation or decay. If neutrinos are among the decay products, then IceCube and other neutrino observatories could detect them. We investigate this scenario for dark matter particles above $m_{chi} gtrsim$ PeV producing tau neutrino signals. At these energies, tau neutrino regeneration is an important effect during propagation through Earth, allowing detection at distances far longer than one interaction length. We show how large energy loss of tau leptons above $sim$ PeVRead More →

New Constraints on Cosmic Particle Populations at the Galactic Center using X-ray Observations of the Molecular Cloud Sagittarius B2. (arXiv:2108.13399v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Rogers_F/0/1/0/all/0/1">Field Rogers</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zhang_S/0/1/0/all/0/1">Shuo Zhang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Perez_K/0/1/0/all/0/1">Kerstin Perez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Clavel_M/0/1/0/all/0/1">Ma&#xef;ca Clavel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Taylor_A/0/1/0/all/0/1">Afura Taylor</a> Located $sim100$ pc from the dynamic center of the Milky Way, the molecular cloud Sagittarius B2 (Sgr B2) is the most massive such object in the Galactic Center region. In X-rays, Sgr B2 shows a prominent neutral Fe K$alpha$ line at 6.4 keV and continuum emission beyond 10 keV, indicating high-energy, non-thermal processes in the cloud. The Sgr B2 complex is an X-ray reflection nebula whose total emissions haveRead More →

Noisy Labels for Weakly Supervised Gamma Hadron Classification. (arXiv:2108.13396v1 [cs.LG]) <a href="http://arxiv.org/find/cs/1/au:+Pfahler_L/0/1/0/all/0/1">Lukas Pfahler</a>, <a href="http://arxiv.org/find/cs/1/au:+Bunse_M/0/1/0/all/0/1">Mirko Bunse</a>, <a href="http://arxiv.org/find/cs/1/au:+Morik_K/0/1/0/all/0/1">Katharina Morik</a> Gamma hadron classification, a central machine learning task in gamma ray astronomy, is conventionally tackled with supervised learning. However, the supervised approach requires annotated training data to be produced in sophisticated and costly simulations. We propose to instead solve gamma hadron classification with a noisy label approach that only uses unlabeled data recorded by the real telescope. To this end, we employ the significance of detection as a learning criterion which addresses this form of weak supervision. We show that models which are based on theRead More →

Multi-wavelength Optical and NIR Variability Analysis of the Blazar PKS 0027-426. (arXiv:2108.13386v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Guise_E/0/1/0/all/0/1">E. Guise</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Honig_S/0/1/0/all/0/1">S. F. H&#xf6;nig</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Almeyda_T/0/1/0/all/0/1">T. Almeyda</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Horne_K/0/1/0/all/0/1">K. Horne</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kishimoto_M/0/1/0/all/0/1">M. Kishimoto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Aguena_M/0/1/0/all/0/1">M. Aguena</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Allam_S/0/1/0/all/0/1">S. Allam</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Andrade_Oliveira_F/0/1/0/all/0/1">F. Andrade-Oliveira</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Asorey_J/0/1/0/all/0/1">J. Asorey</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Banerji_M/0/1/0/all/0/1">M. Banerji</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bertin_E/0/1/0/all/0/1">E. Bertin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boulderstone_B/0/1/0/all/0/1">B. Boulderstone</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Brooks_D/0/1/0/all/0/1">D. Brooks</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burke_D/0/1/0/all/0/1">D. L. Burke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rosell_A/0/1/0/all/0/1">A. Carnero Rosell</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Carollo_D/0/1/0/all/0/1">D. Carollo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kind_M/0/1/0/all/0/1">M. Carrasco Kind</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Carretero_J/0/1/0/all/0/1">J. Carretero</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Costanzi_M/0/1/0/all/0/1">M. Costanzi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Costa_L/0/1/0/all/0/1">L. N. da Costa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Davis_T/0/1/0/all/0/1">T. M. Davis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vicente_J/0/1/0/all/0/1">J. De Vicente</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Doel_P/0/1/0/all/0/1">P. Doel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Everett_S/0/1/0/all/0/1">S. Everett</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ferrero_I/0/1/0/all/0/1">I. Ferrero</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Flaugher_B/0/1/0/all/0/1">B. Flaugher</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Frieman_J/0/1/0/all/0/1">J. Frieman</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gandhi_P/0/1/0/all/0/1">P. Gandhi</a>,Read More →

MOJAVE: XVIII. Kinematics and Inner Jet Evolution of Bright Radio-Loud Active Galaxies. (arXiv:2108.13358v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Lister_M/0/1/0/all/0/1">M. L. Lister</a> (Purdue U), <a href="http://arxiv.org/find/astro-ph/1/au:+Homan_D/0/1/0/all/0/1">D. C. Homan</a> (Denison U), <a href="http://arxiv.org/find/astro-ph/1/au:+Kellermann_K/0/1/0/all/0/1">K. I. Kellermann</a> (NRAO), <a href="http://arxiv.org/find/astro-ph/1/au:+Kovalev_Y/0/1/0/all/0/1">Y. Y. Kovalev</a> (ASC Lebedev, MIPT, MPIfR), <a href="http://arxiv.org/find/astro-ph/1/au:+Pushkarev_A/0/1/0/all/0/1">A. B. Pushkarev</a> (CrAO, ASC Lebedev, MIPT), <a href="http://arxiv.org/find/astro-ph/1/au:+Ros_E/0/1/0/all/0/1">E. Ros</a> (MPIfR), <a href="http://arxiv.org/find/astro-ph/1/au:+Savolainen_T/0/1/0/all/0/1">T. Savolainen</a> (Aalto U, MPIfR) We have analyzed the parsec-scale jet kinematics of 447 bright radio-loud AGN, based on 15 GHz VLBA data obtained between 1994 August 31 and 2019 August 4. We present new total intensity and linear polarization maps obtained between 2017 January 1 to 2019 August 4 for 143 ofRead More →

Dark Matter, Rotation Curves, and the Morphology of Galaxies. (arXiv:2108.13350v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Zatrimaylov_K/0/1/0/all/0/1">Kirill Zatrimaylov</a> In this thesis, we investigate some aspects of dark matter phenomenology and its predictive power in explaining the flattening of galaxy rotation curves at large distances. After outlining the Standard Model of particle physics, its symmetries and possible extensions in Chapter 2, we review key facts about dark matter and various types of dark matter models in Chapter 3. In Chapter 4 we discuss some alternatives to cold dark matter, which include modified Newtonian dynamics (MOND), superfluid dark matter and emergent gravity, and highlight the difficulties that are encountered in attemptsRead More →

Fitting spectral energy distributions of FMOS-COSMOS emission-line galaxies at z$sim$1.6: Star formation rates, dust attenuation, and [OIII]$lambda$5007 emission-line luminosities. (arXiv:2108.13321v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Villa_Velez_J/0/1/0/all/0/1">J. A. Villa-V&#xe9;lez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Buat_V/0/1/0/all/0/1">V. Buat</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Theule_P/0/1/0/all/0/1">P. Theul&#xe9;</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boquien_M/0/1/0/all/0/1">M. Boquien</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burgarella_D/0/1/0/all/0/1">D. Burgarella</a> We perform SED fitting analysis on a COSMOS sample covering UV-to-FIR wavelengths with emission lines from the FMOS survey. The sample of 182 objects with H$alpha$ and [OIII]$lambda5007$ emission spans over a range of $1.40<rm{z}<1.68$. We obtain robust estimates of stellar mass ($10^{9.5}-10^{11.5}~rm{M_odot}$) and SFR ($10^1-10^3~rm{M_odot}~rm{yr}^{-1}$) from the Bayesian analysis with CIGALE fitting continuum photometry and H$alpha$. We obtain a median attenuation of A$_rm{Halpha}=1.16pm0.19$ mag and A$_rm{[OIII]}=1.41pm0.22$ mag.Read More →

Interacting dark energy axions in light of the Hubble tension. (arXiv:2108.13317v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Mawas_E/0/1/0/all/0/1">Ennis Mawas</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Street_L/0/1/0/all/0/1">Lauren Street</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gass_R/0/1/0/all/0/1">Richard Gass</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wijewardhana_L/0/1/0/all/0/1">L.C.R. Wijewardhana</a> A current problem within the {Lambda}CDM framework is the tension between late and early time measurements of the Hubble parameter today, H0. We entertain the possibility that dark energy modeled as multiple interacting axion-like-particle species can alleviate the current Hubble tension. We then test these parameters against the milder tension between the CMB and large scale structure (LSS) observations of {sigma}8 to ensure that these models do not exacerbate the tension. We find that there exist parameter spaces for models ofRead More →

Learning the Lantern: Neural network applications to broadband photonic lantern modelling. (arXiv:2108.13274v1 [physics.optics]) <a href="http://arxiv.org/find/physics/1/au:+Sweeney_D/0/1/0/all/0/1">David Sweeney</a>, <a href="http://arxiv.org/find/physics/1/au:+Norris_B/0/1/0/all/0/1">Barnaby R. M. Norris</a>, <a href="http://arxiv.org/find/physics/1/au:+Tuthill_P/0/1/0/all/0/1">Peter Tuthill</a>, <a href="http://arxiv.org/find/physics/1/au:+Scalzo_R/0/1/0/all/0/1">Richard Scalzo</a>, <a href="http://arxiv.org/find/physics/1/au:+Wei_J/0/1/0/all/0/1">Jin Wei</a>, <a href="http://arxiv.org/find/physics/1/au:+Betters_C/0/1/0/all/0/1">Christopher H. Betters</a>, <a href="http://arxiv.org/find/physics/1/au:+Leon_Saval_S/0/1/0/all/0/1">Sergio G. Leon-Saval</a> Photonic lanterns allow the decomposition of highly multimodal light into a simplified modal basis such as single-moded and/or few-moded. They are increasingly finding uses in astronomy, optics and telecommunications. Calculating propagation through a photonic lantern using traditional algorithms takes $sim 1$ hour per simulation on a modern CPU. This paper demonstrates that neural networks can bridge the disparate opto-electronic systems, and when trained can achieve a speed-upRead More →

Low-surface-brightness spheroidal galaxies as Milgromian isothermal spheres. (arXiv:2104.03861v4 [astro-ph.GA] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Sanders_R/0/1/0/all/0/1">R.H. Sanders</a> I consider a sample of eight pressure-supported low-surface brightness galaxies in terms of Milgrom’s modified Newtonian dynamics (MOND). These objects include seven nearby dwarf spheroidal galaxies — Sextans, Carina, Leo II, Sculptor, Draco, Leo I, Fornax, and the ultra-diffuse galaxy DF44. The objects are modelled as Milgromian isotropic isothermal spheres characterised by two parameters that are constrained by observations: the constant line-of-sight velocity dispersion and the central surface density. The velocity dispersion determines the total mass, and, with the implied mass-to-light ratio, the central surface brightness. This then specifies the radial runRead More →

“Worst-Case” Micro-Lensing in the Identification and Modeling of Lensed Quasars. (arXiv:2105.08690v2 [astro-ph.GA] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Weisenbach_L/0/1/0/all/0/1">Luke Weisenbach</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schechter_P/0/1/0/all/0/1">Paul Schechter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pontula_S/0/1/0/all/0/1">Sahil Pontula</a> Although micro-lensing of macro-lensed quasars and supernovae provides unique opportunities for several kinds of investigations, it can add unwanted and sometimes substantial noise. While micro-lensing flux anomalies may be safely ignored for some observations, they severely limit others. “Worst-case” estimates can inform the decision whether or not to undertake an extensive examination of micro-lensing scenarios. Here, we report “worst-case” micro-lensing uncertainties for point sources lensed by singular isothermal potentials, parameterized by a convergence equal to the shear and by the stellar fraction. TheRead More →

21-cm constraints on spinning primordial black holes. (arXiv:2108.13256v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Cang_J/0/1/0/all/0/1">Junsong Cang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gao_Y/0/1/0/all/0/1">Yu Gao</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ma_Y/0/1/0/all/0/1">Yin-Zhe Ma</a> Hawking radiation from primordial black holes (PBH) can ionize and heat up neutral gas during the cosmic dark ages, leaving imprints on the global 21cm signal of neutral hydrogen. We use the global 21cm signal to constrain the abundance of spinning PBHs in mass range of $[2 times 10^{13}, 10^{18}]$ grams. We consider several extended PBH distribution models. Our results show that 21cm can set the most stringent PBH bounds in our mass window. Compared with constraints set by {it{Planck}} cosmic microwave background (CMB) data, 21-cm limitsRead More →

Black hole gravitational potential enhanced fallback accretion onto the nascent lighter compact object: tentative evidence in the O3 run data of LIGO/Virgo. (arXiv:2107.08811v2 [astro-ph.HE] UPDATED) <a href="http://arxiv.org/find/astro-ph/1/au:+Tang_S/0/1/0/all/0/1">Shao-Peng Tang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Li_Y/0/1/0/all/0/1">Yin-Jie Li</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_Y/0/1/0/all/0/1">Yuan-Zhu Wang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fan_Y/0/1/0/all/0/1">Yi-Zhong Fan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wei_D/0/1/0/all/0/1">Da-Ming Wei</a> In a binary system, the gravitational potential of the primary black hole may play an important role in enhancing the fallback accretion onto the lighter compact object newly formed in the second supernova explosion. As a result, the final masses of the binary compact objects would be correlated, as suggested recently by Safarzadeh & Wysocki (2021). In this work, we analyze the mass distribution ofRead More →

On the primordial correlation of gravitons with gauge fields. (arXiv:2108.10887v1 [hep-th] CROSS LISTED) <a href="http://arxiv.org/find/hep-th/1/au:+Jain_R/0/1/0/all/0/1">Rajeev Kumar Jain</a>, <a href="http://arxiv.org/find/hep-th/1/au:+Sai_P/0/1/0/all/0/1">P. Jishnu Sai</a>, <a href="http://arxiv.org/find/hep-th/1/au:+Sloth_M/0/1/0/all/0/1">Martin S. Sloth</a> We calculate the primordial correlation of gravitons with an abelian gauge field non-minimally coupled through a dynamical dilaton field or a volume moduli during inflation in the early universe. In particular, we compute the cross-correlation of a tensor mode with two gauge field modes and the corresponding correlation functions for the associated magnetic and electric fields using the in-in formalism. Moreover, using semi-classical methods, we show that the three-point cross-correlation functions satisfy new consistency relations (soft theorems) in the squeezedRead More →