Detection of gravitational wave polarization with single space-based detectors. (arXiv:2102.03972v2 [gr-qc] UPDATED) <a href="">Chao Zhang</a>, <a href="">Yungui Gong</a>, <a href="">Dicong Liang</a>, <a href="">Chunyu Zhang</a> General Relativity predicts only two tensor polarization modes for gravitational waves while at most six possible polarization modes are allowed in general metric theory of gravity. The number of polarization modes is determined by the specific modified theory of gravity. Therefore, the determination of polarization modes can be used to test gravitational theory. We introduce a concrete data analysis pipeline for a space-based detector such as LISA to detect the polarization modes of gravitational waves. This method can be used forRead More →

One star, two star, red star, blue star: an updated planetary nebula central star distance catalogue from Gaia EDR3. (arXiv:2102.13654v2 [astro-ph.SR] UPDATED) <a href="">N. Chornay</a>, <a href="">N.A. Walton</a> Context. Planetary nebulae (PNe) are a brief but important phase of stellar evolution. The study of Galactic PNe has historically been hampered by uncertain distances, but the parallaxes of PN central stars (CSPNe) measured by Gaia are improving the situation. Aims. Gaia’s Early Data Release 3 (EDR3) offers higher astrometric precision and greater completeness compared to previous releases. Taking advantage of these improvements requires that the CSPNe in the catalogue be accurately identified. Methods. We applied ourRead More →

Radio antenna design for sky-averaged 21 cm cosmology experiments: the REACH case. (arXiv:2109.10098v1 [astro-ph.IM]) <a href="">J. Cumner</a>, <a href="">E. De Lera Acedo</a>, <a href="">D.I.L. de Villiers</a>, <a href="">D. Anstey</a>, <a href="">C. I. Kolitsidas</a>, <a href="">B. Gurdon</a>, <a href="">N. Fagnoni</a>, <a href="">P. Alexander</a>, <a href="">G. Bernardi</a>, <a href="">H.T.J. Bevins</a>, <a href="">S. Carey</a>, <a href="">J. Cavillot</a>, <a href="">R. Chiello</a>, <a href="">C. Craeye</a>, <a href="">W. Croukamp</a>, <a href="">J.A. Ely</a>, <a href="">A. Fialkov</a>, <a href="">T. Gessey-Jones</a>, <a href="">Q. Gueuning</a>, <a href="">W. Handley</a>, <a href="">R. Hills</a>, <a href="">A.T. Josaitis</a>, <a href="">G. Kulkarni</a>, <a href="">A. Magro</a>, <a href="">R. Maiolino</a>, <a href="">P. D. Meerburg</a>, <a href="">S. Mittal</a>, <a href="">J.R. Pritchard</a>, <a href="">E.Read More →

A Near-infrared Survey of UV-excited Molecular Hydrogen in Photodissociation Regions. (arXiv:2108.08484v2 [astro-ph.GA] UPDATED) <a href="">Kyle F. Kaplan</a>, <a href="">Harriet L. Dinerstein</a>, <a href="">Hwihyun Kim</a>, <a href="">Daniel T. Jaffe</a> We present a comparative study of the near-infrared (NIR) H$_2$ line emission from five regions near hot young stars: Sharpless 140, NGC 2023, IC 63, the Horsehead Nebula, and the Orion Bar. This emission originates in photodissociation or photon-dominated regions (PDRs), interfaces between photoionized and molecular gas near hot (O) stars or reflection nebulae illuminated by somewhat cooler (B) stars. In these environments, the dominant excitation mechanism for NIR emission lines originating from excited rotational-vibrational (rovibrational) levelsRead More →

Reflexive Behaviour: How publication pressure affects research quality in Astronomy. (arXiv:2109.09375v2 [physics.soc-ph] UPDATED) <a href="">Julia Heuritsch</a> Reflexive metrics is a branch of science studies which explores how the demand for accountability and performance measurement in science has shaped the research culture in recent decades. Hypercompetition and publication pressure are part of this neoliberal culture. How do scientists respond to these pressures? Studies on research integrity and organizational culture suggest that people who feel treated unfairly by their institution are more likely to engage in deviant behaviour, such as scientific misconduct. By building up on reflexive metrics, combined with studies on the influence of organisational cultureRead More →

A sudden period of high activity from repeating Fast Radio Burst 20201124A. (arXiv:2109.09254v2 [astro-ph.HE] UPDATED) <a href="">Adam E. Lanman</a>, <a href="">Bridget C. Andersen</a>, <a href="">Pragya Chawla</a>, <a href="">Alexander Josephy</a>, <a href="">Victoria M. Kaspi</a>, <a href="">Kevin Bandura</a>, <a href="">Mohit Bhardwaj</a>, <a href="">Patrick J. Boyle</a>, <a href="">Charanjot Brar</a>, <a href="">Daniela Breitman</a>, <a href="">Tomas Cassanelli</a>, <a href="">Fengqi Dong</a>, <a href="">Emmanuel Fonseca</a>, <a href="">Bryan M. Gaensler</a>, <a href="">Deborah Good</a>, <a href="">Jane Kaczmarek</a>, <a href="">Calvin Leung</a>, <a href="">Kiyoshi W. Masui</a>, <a href="">Bradley W. Meyers</a>, <a href="">Cherry Ng</a>, <a href="">Chitrang Patel</a>, <a href="">Aaron B. Pearlman</a>, <a href="">Emily Petroff</a>, <a href="">Ziggy Pleunis</a>, <a href="">Masoud Rafiei-Ravandi</a>, <a href="">Mubdi Rahman</a>, <a href="">Pranav Sanghavi</a>, <aRead More →

DECORAS: detection and characterization of radio-astronomical sources using deep learning. (arXiv:2109.09077v2 [astro-ph.IM] UPDATED) <a href="">S.Rezaei</a>, <a href="">J.P.McKean</a>, <a href="">M.Biehl</a>, <a href="">A.Javadpour</a> We present DECORAS, a deep learning based approach to detect both point and extended sources from Very Long Baseline Interferometry (VLBI) observations. Our approach is based on an encoder-decoder neural network architecture that uses a low number of convolutional layers to provide a scalable solution for source detection. In addition, DECORAS performs source characterization in terms of the position, effective radius and peak brightness of the detected sources. We have trained and tested the network with images that are based on realistic Very LongRead More →

An extreme case of galaxy and cluster co-evolution at $z$=0.7. (arXiv:2109.08798v2 [astro-ph.GA] UPDATED) <a href="">Harald Ebeling</a>, <a href="">Johan Richard</a>, <a href="">Ian Smail</a>, <a href="">Alastair Edge</a>, <a href="">Anton Koekemoer</a>, <a href="">Lukas Zalesky</a> We report the discovery of eMACSJ0252.4$-$2100 (eMACSJ0252), a massive and highly evolved galaxy cluster at $z=0.703$. Our analysis of Hubble Space Telescope imaging and VLT/MUSE and Keck/DEIMOS spectroscopy of the system finds a high velocity dispersion of 1020$^{+180}_{-190}$ km s$^{-1}$ and a high (if tentative) X-ray luminosity of $(1.2pm 0.4)times10^{45}$ erg s$^{-1}$ (0.1$-$2.4 keV). As extreme is the system’s brightest cluster galaxy, a giant cD galaxy that forms stars at a rate of betweenRead More →

Molecules with ALMA at Planet-forming Scales (MAPS) XIV: Revealing disk substructures in multi-wavelength continuum emission. (arXiv:2109.06433v2 [astro-ph.EP] UPDATED) <a href="">Anibal Sierra</a>, <a href="">Laura M. P&#xe9;rez</a>, <a href="">Ke Zhang</a>, <a href="">Charles J. Law</a>, <a href="">Viviana V. Guzm&#xe1;n</a>, <a href="">Chunhua Qi</a>, <a href="">Arthur D. Bosman</a>, <a href="">Karin I. &#xd6;berg</a>, <a href="">Sean M. Andrews</a>, <a href="">Feng Long</a>, <a href="">Richard Teague</a>, <a href="">Alice S. Booth</a>, <a href="">Catherine Walsh</a>, <a href="">David J. Wilner</a>, <a href="">Fran&#xe7;ois M&#xe9;nard</a>, <a href="">Gianni Cataldi</a>, <a href="">Ian Czekala</a>, <a href="">Jaehan Bae</a>, <a href="">Jane Huang</a>, <a href="">Jennifer B. Bergner</a>, <a href="">John D. Ilee</a>, <a href="">Myriam Benisty</a>, <a href="">Romane Le Gal</a>, <a href="">Ryan A. Loomis</a>, <a href="">Takashi Tsukagoshi</a>,Read More →

Hubble tension or a transition of the Cepheid SnIa calibrator parameters?. (arXiv:2109.04406v2 [astro-ph.CO] UPDATED) <a href="">Leandros Perivolaropoulos</a>, <a href="">Foteini Skara</a> We re-analyze the Cepheid data used to infer the value of $H_0$ by calibrating SnIa. We do not enforce a universal value of the empirical Cepheid calibration parameters $R_W$ (Cepheid Wesenheit color-luminosity parameter) and $M_H^{W}$ (Cepheid Wesenheit H-band absolute magnitude). Instead, we allow for variation of either of these parameters for each individual galaxy. We also consider the case where these parameters have two universal values: one for low galactic distances $D<D_c$ and one for high galactic distances $D>D_c$ where $D_c$ is a critical transitionRead More →

Spectral evolution of an eruptive polar crown prominence with IRIS observations. (arXiv:2109.02908v2 [astro-ph.SR] UPDATED) <a href="">Jianchao Xue</a>, <a href="">Hui Li</a>, <a href="">Yang Su</a> Prominence eruption is closely related to coronal mass ejections and is an important topic in solar physics. Spectroscopic observation is an effective way to explore the plasma properties, but the spectral observations of eruptive prominences are rare. In this paper we will introduce an eruptive polar crown prominence with spectral observations from the Interface Region Imaging Spectrograph (IRIS), and try to explain some phenomena that are rarely reported in previous works. The eruptive prominence experiences a slow-rise and fast-rise phase, while theRead More →

Properties of Polarized Synchrotron Emission from Fluctuation Dynamo Action — II. Effects of Turbulence Driving in the ICM and Beam Smoothing. (arXiv:2108.13945v2 [astro-ph.GA] UPDATED) <a href="">Aritra Basu</a>, <a href="">Sharanya Sur</a> Polarized synchrotron emission from the radio halos of diffuse intracluster medium (ICM) in galaxy clusters are yet to be observed. To investigate the expected polarization in the ICM, we use high resolution ($1$,kpc) magnetohydrodynamic simulations of fluctuation dynamos, which produces intermittent magnetic field structures, for varying scales of turbulent driving ($l_{rm f}$) to generate synthetic observations of the polarized emission. We focus on how the inferred diffuse polarized emission for different $l_{rm f}$ is affectedRead More →

Galaxy and Mass Assembly (GAMA): Tracing galaxy environment using the marked correlation function. (arXiv:2102.04177v3 [astro-ph.CO] UPDATED) <a href="">U. Sureshkumar</a>, <a href="">A. Durkalec</a>, <a href="">A. Pollo</a>, <a href="">M. Bilicki</a>, <a href="">J. Loveday</a>, <a href="">D. J. Farrow</a>, <a href="">B. W. Holwerda</a>, <a href="">A. M. Hopkins</a>, <a href="">J. Liske</a>, <a href="">K. A. Pimbblet</a>, <a href="">E. N. Taylor</a>, <a href="">A. H. Wright</a> We investigate how different galaxy properties – luminosities in u, g, r, J, K-bands, stellar mass, star formation rate and specific star formation rate trace the environment in the local universe. We also study the effect of survey flux limits on galaxy clustering measurements. We measure theRead More →

Negative Turbulent Magnetic Diffusivity $beta$ effect in a Magnetically Forced System. (arXiv:2102.03500v4 [physics.plasm-ph] UPDATED) <a href="">Kiwan Park</a>, <a href="">Myung-Ki Cheoun</a> We have studied the large scale dynamo process forced with helical magnetic energy. The magnetically driven dynamo is not so well studied as kinetically forced dynamo. It has been thought to represent the amplification of magnetic field in the stellar corona, accretion disk, or plasma lab. However, the interaction between the helical magnetic field and plasma is a more fundamental phenomenon that can be extended to the early Universe. The scale-invariant helical magnetic field not only explains the currently observed large scale astrophysical magnetic fieldsRead More →

Consequences of constant elevation scans for instrumental systematics in Cosmic Microwave Background Experiments. (arXiv:2102.02284v2 [astro-ph.IM] UPDATED) <a href="">Daniel B. Thomas</a>, <a href="">Nialh McCallum</a>, <a href="">Michael L. Brown</a> Instrumental systematics need to be controlled to high precision for upcoming Cosmic Microwave Background (CMB) experiments. The level of contamination caused by these systematics is often linked to the scan strategy, and scan strategies for satellite experiments can significantly mitigate these systematics. However, no detailed study has been performed for ground-based experiments. Here we show that under the assumption of constant elevation scans (CESs), the ability of the scan strategy to mitigate these systematics is strongly limited, irrespectiveRead More →

Lensing magnification: gravitational waves from coalescing stellar-mass binary black holes. (arXiv:2012.08381v3 [astro-ph.CO] UPDATED) <a href="">Xikai Shan</a>, <a href="">Chengliang Wei</a>, <a href="">Bin Hu</a> Gravitational waves (GWs) may be magnified or de-magnified due to lensing. This phenomenon will bias the distance estimation based on the matched filtering technique. Via the multi-sphere ray-tracing technique, we study the GW magnification effect and selection effect with particular attention to the stellar-mass binary black holes (BBHs). We find that, for the observed luminosity distance $lesssim 3~mathrm{Gpc}$, which is the aLIGO/Virgo observational horizon limit, the average magnification keeps as unity, namely unbiased estimation, with the relative distance uncertainty $sigma(hat{d})/hat{d}simeq0.5%sim1%$. Beyond this observationalRead More →

The Payload for Ultrahigh Energy Observations (PUEO): A White Paper. (arXiv:2010.02892v3 [astro-ph.IM] UPDATED) <a href="">Q. Abarr</a>, <a href="">P. Allison</a>, <a href="">J. Ammerman Yebra</a>, <a href="">J. Alvarez-Mu&#xf1;iz</a>, <a href="">J. J. Beatty</a>, <a href="">D. Z. Besson</a>, <a href="">P. Chen</a>, <a href="">Y. Chen</a>, <a href="">J. M. Clem</a>, <a href="">A. Connolly</a>, <a href="">L. Cremonesi</a>, <a href="">C. Deaconu</a>, <a href="">J. Flaherty</a>, <a href="">D. Frikken</a>, <a href="">P. W. Gorham</a>, <a href="">C. Hast</a>, <a href="">C. Hornhuber</a>, <a href="">J.J. Huang</a>, <a href="">K. Hughes</a>, <a href="">A. Hynous</a>, <a href="">Y. Ku</a>, <a href="">C.-Y. Kuo</a>, <a href="">T. C. Liu</a>, <a href="">Z. Martin</a>, <a href="">C. Miki</a>, <a href="">J. Nam</a>, <a href="">R. J. Nichol</a>, <a href="">K. Nishimura</a>, <aRead More →

Equation of states in the curved spacetime of spherical degenerate stars. (arXiv:2005.08783v2 [gr-qc] UPDATED) <a href="">Golam Mortuza Hossain</a>, <a href="">Susobhan Mandal</a> In the study of spherical degenerate stars such as neutron stars, general relativistic effects are incorporated by using Tolman-Oppenheimer-Volkoff equations to describe their interior spacetime. However, the equation of states employed in such studies are invariably computed in flat spacetime. We show that the equation of states computed in the curved spacetime of these stars depend explicitly on the metric function. Further, we show that ignoring such metric-dependent gravitational time dilation effect leads one to grossly underestimate the mass limits of these compact stars.Read More →

Primordial flat frame — a new view on inflation. (arXiv:2003.08908v4 [gr-qc] UPDATED) <a href="">C. Wetterich</a> Models of inflationary cosmology admit a choice of the metric for which the geometry of homogeneous isotropic solutions becomes flat Minkowski space in the infinite past. In this primordial flat frame all mass scales vanish in the infinite past and quantum scale symmetry is realized. The cosmological evolution is dominantly described by the slow increase of a scalar field which sets the scale of all masses. We construct the primordial flat frame for standard models of inflation as Starobinsky inflation or chaotic inflation. In particular, we discuss the evolution ofRead More →

Lithium Enrichment Signatures of Planetary Engulfment Events in Evolved Stars. (arXiv:2002.05275v2 [astro-ph.SR] UPDATED) <a href="">M. Soares-Furtado</a>, <a href="">Matteo Cantiello</a>, <a href="">Morgan MacLeod</a>, <a href="">Melissa K. Ness</a> Planetary engulfment events have long been proposed as a lithium (Li) enrichment mechanism contributing to the population of Li-rich giants (A(Li) >= 1.5 dex). Using MESA stellar models and A(Li) abundance measurements obtained by the GALAH survey, we calculate the strength and observability of the surface Li enrichment signature produced by the engulfment of a hot Jupiter (HJ). We consider solar-metallicity stars in the mass range of 1-2 $mathrm{M_odot}$ and the Li supplied by a HJ of 1.0 $mathrm{M_J}$.Read More →