RAS_WEB (Page 2,755)

Brans-Dicke theory in Bondi-Sachs form: Asymptotically flat solutions, asymptotic symmetries and gravitational-wave memory effects. (arXiv:2007.13799v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Tahura_S/0/1/0/all/0/1">Shammi Tahura</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Nichols_D/0/1/0/all/0/1">David A. Nichols</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Saffer_A/0/1/0/all/0/1">Alexander Saffer</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Stein_L/0/1/0/all/0/1">Leo C. Stein</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Yagi_K/0/1/0/all/0/1">Kent Yagi</a> Gravitational-wave memory effects are identified by their distinctive effects on families of freely falling observers: after a burst of waves pass by their locations, memory effects can cause lasting relative displacements of the observers. These effects are closely related to the infrared properties of gravity and other massless field theories, including their asymptotic symmetries and conserved quantities. In this paper, we investigate the connection between memory effects, symmetries, and conserved quantities inRead More →

Parametrization of the angular distribution of Cherenkov light in air showers. (arXiv:2007.13812v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Arbeletche_L/0/1/0/all/0/1">Luan Arbeletche</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Souza_V/0/1/0/all/0/1">Vitor de Souza</a> The Cherenkov light produced in air showers largely contributes to the signal observed in gamma-ray and cosmic-ray observatories. Yet, no description of this phenomenon is available covering both small and large angular regions. To fill this gap, a parametrization of the angular distribution of Cherenkov photons is performed in terms of a physically motivated parametric function. Model parameters are constrained using simulated gamma-ray and proton showers with energies in the TeV to EeV region. As a result, a parametrization is obtained that overcomes in precisionRead More →

The structure of the co-orbital stable regions as a function of the mass ratio. (arXiv:2007.13814v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Liberato_L/0/1/0/all/0/1">L. Liberato</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Winter_O/0/1/0/all/0/1">O. Winter</a> Although the search for extra-solar co-orbital bodies has not had success so far, it is believed that they must be as common as they are in the Solar System. Co-orbital systems have been widely studied, and there are several works on stability and even on formation. However, for the size and location of the stable regions, authors usually describe their results but do not provide a way to find them without numerical simulations, and, in most cases, the mass ratio value range isRead More →

The look-elsewhere effect from a unified Bayesian and frequentist perspective. (arXiv:2007.13821v1 [physics.data-an]) <a href="http://arxiv.org/find/physics/1/au:+Bayer_A/0/1/0/all/0/1">Adrian E. Bayer</a>, <a href="http://arxiv.org/find/physics/1/au:+Seljak_U/0/1/0/all/0/1">Uros Seljak</a> When searching over a large parameter space for anomalies such as events, peaks, objects, or particles, there is a large probability that spurious signals with seemingly high significance will be found. This is known as the look-elsewhere effect and is prevalent throughout cosmology, (astro)particle physics, and beyond. To avoid making false claims of detection, one must account for this effect when assigning the statistical significance of an anomaly. This is typically accomplished by considering the trials factor, which is generally computed numerically via potentially expensive simulations.Read More →

Solar Flare Arcade Modelling: Bridging the gap from 1D to 3D Simulations of Optically Thin Radiation. (arXiv:2007.13856v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Kerr_G/0/1/0/all/0/1">Graham S. Kerr</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Allred_J/0/1/0/all/0/1">Joel C. Allred</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Polito_V/0/1/0/all/0/1">Vanessa Polito</a> Solar flares are 3D phenomenon but modelling a flare in 3D, including many of the important processes in the chromosphere, is a computational challenge. Accurately modelling the chromosphere is important, even if the transition region and corona are the areas of interest, due to the flow of energy, mass, and radiation through the interconnected layers. We present a solar flare arcade model, that aims to bridge the gap between 1D and 3D modelling. Our approach isRead More →

Limits to Rest-Frame Ultraviolet Emission From Far-Infrared-Luminous z~6 Quasar Hosts. (arXiv:2007.13859v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Marshall_M/0/1/0/all/0/1">Madeline A. Marshall</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mechtley_M/0/1/0/all/0/1">Mira Mechtley</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Windhorst_R/0/1/0/all/0/1">Rogier A. Windhorst</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Cohen_S/0/1/0/all/0/1">Seth H. Cohen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jansen_R/0/1/0/all/0/1">Rolf A. Jansen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jiang_L/0/1/0/all/0/1">Linhua Jiang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jones_V/0/1/0/all/0/1">Victoria R. Jones</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wyithe_J/0/1/0/all/0/1">J. Stuart B. Wyithe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fan_X/0/1/0/all/0/1">Xiaohui Fan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hathi_N/0/1/0/all/0/1">Nimish P. Hathi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jahnke_K/0/1/0/all/0/1">Knud Jahnke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Keel_W/0/1/0/all/0/1">William C. Keel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Koekemoer_A/0/1/0/all/0/1">Anton M. Koekemoer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Marian_V/0/1/0/all/0/1">Victor Marian</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ren_K/0/1/0/all/0/1">Keven Ren</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Robinson_J/0/1/0/all/0/1">Jenna Robinson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rottgering_H/0/1/0/all/0/1">Huub J. A. R&#xf6;ttgering</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ryan_R/0/1/0/all/0/1">Russell E. Ryan Jr.</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Scannapieco_E/0/1/0/all/0/1">Evan Scannapieco</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schneider_D/0/1/0/all/0/1">Donald P. Schneider</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schneider_G/0/1/0/all/0/1">Glenn Schneider</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Smith_B/0/1/0/all/0/1">Brent M. Smith</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yan_H/0/1/0/all/0/1">Haojing Yan</a> We report on a Hubble Space Telescope searchRead More →

MATLAS: a deep exploration of the surroundings of massive early-type galaxies. (arXiv:2007.13874v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Duc_P/0/1/0/all/0/1">Pierre-Alain Duc</a> The MATLAS project explores the surroundings of a complete sample of nearby massive early-type galaxies with multi-colour deep optical images obtained at the Canada-France Hawaii Telescope. The observing and data reduction techniques ensured the detection of extended low-surface-brightness (LSB) structures, while the high image quality allowed us to identify associated compact objects such as star clusters. A number of scientific topics are addressed with this data-set that are briefly presented in this review: the study of foreground Galactic cirrus at high spatial resolution, telling us about the ISM structure;Read More →

Estimating Satellite Orbital Drag During Historical Magnetic Superstorms. (arXiv:2007.13892v1 [physics.space-ph]) <a href="http://arxiv.org/find/physics/1/au:+Oliveira_D/0/1/0/all/0/1">Denny M. Oliveira</a>, <a href="http://arxiv.org/find/physics/1/au:+Zesta_E/0/1/0/all/0/1">Eftyhia Zesta</a>, <a href="http://arxiv.org/find/physics/1/au:+Hayakawa_H/0/1/0/all/0/1">Hisashi Hayakawa</a>, <a href="http://arxiv.org/find/physics/1/au:+Bhaskar_A/0/1/0/all/0/1">Ankush Bhaskar</a> Understanding extreme space weather events is of paramount importance in efforts to protect technological systems in space and on the ground. Particularly in the thermosphere, the subsequent extreme magnetic storms can pose serious threats to low-Earth orbit (LEO) spacecraft by intensifying errors in orbit predictions. Extreme magnetic storms (minimum Dst $leq$ –250 nT) are extremely rare: only 7 events occurred during the era of spacecraft with high-level accelerometers such as CHAMP (CHAllenge Mini-satellite Payload) and GRACE (Gravity Recovery And Climate experiment), andRead More →

Constraints on cosmological parameters from gamma-ray burst peak photon energy and bolometric fluence measurements and other data. (arXiv:2007.13907v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Khadka_N/0/1/0/all/0/1">Narayan Khadka</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ratra_B/0/1/0/all/0/1">Bharat Ratra</a> We use measurements of the peak photon energy and bolometric fluence of 119 gamma-ray bursts (GRBs) extending over the redshift range of $0.3399 leq z leq 8.2$ to simultaneously determine cosmological and Amati relation parameters in six different cosmological models. The resulting Amati relation parameters are almost identical in all six cosmological models, thus validating the use of the Amati relation in standardizing these GRBs. The GRB data cosmological parameter constraints are consistent with, but significantly less restrictive than, thoseRead More →

The Importance of Prioritizing Exoplanet Experimental Facilities. (arXiv:2007.13924v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Kohler_E/0/1/0/all/0/1">Erika Kohler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+He_C/0/1/0/all/0/1">Chao He</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Moran_S/0/1/0/all/0/1">Sarah E. Moran</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shim_S/0/1/0/all/0/1">S.-H. Dan Shim</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Brugman_K/0/1/0/all/0/1">Karalee K. Brugman</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Johnson_A/0/1/0/all/0/1">Aleisha C. Johnson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vergeli_P/0/1/0/all/0/1">Pilar C. Vergeli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Thompson_M/0/1/0/all/0/1">Maggie A. Thompson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Graham_H/0/1/0/all/0/1">Heather Graham</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gudipati_M/0/1/0/all/0/1">Murthy S. Gudipati</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fleury_B/0/1/0/all/0/1">Benjamin Fleury</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Henderson_B/0/1/0/all/0/1">Bryana L. Henderson</a> Continuous improvements of observations and modeling efforts have led to tremendous strides in exoplanetary science. However, as instruments and techniques advance laboratory data becomes more important to interpret exoplanet observations and verify theoretical modeling. Though experimental studies are often deferred due to their high costs and long timelines, it is imperative thatRead More →

TESS Reveals a Short-period Sub-Neptune Sibling (HD 86226c) to a Known Long-period Giant Planet. (arXiv:2007.13927v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Teske_J/0/1/0/all/0/1">Johanna Teske</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Diaz_M/0/1/0/all/0/1">Mat&#xed;as R. D&#xed;az</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Luque_R/0/1/0/all/0/1">Rafael Luque</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mocnik_T/0/1/0/all/0/1">Teo Mo&#x10d;nik</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Seidel_J/0/1/0/all/0/1">Julia V. Seidel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Otegi_J/0/1/0/all/0/1">Jon Fern&#xe1;ndez Otegi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Feng_F/0/1/0/all/0/1">Fabo Feng</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jenkins_J/0/1/0/all/0/1">James S. Jenkins</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Palle_E/0/1/0/all/0/1">Enric Pall&#xe8;</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Segransan_D/0/1/0/all/0/1">Damien S&#xe9;gransan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Udry_S/0/1/0/all/0/1">St&#xe8;phane Udry</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Collins_K/0/1/0/all/0/1">Karen A. Collins</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Eastman_J/0/1/0/all/0/1">Jason D. Eastman</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ricker_G/0/1/0/all/0/1">George R. Ricker</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vanderspek_R/0/1/0/all/0/1">Roland Vanderspek</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Latham_D/0/1/0/all/0/1">David W. Latham</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Seager_S/0/1/0/all/0/1">Sara Seager</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Winn_J/0/1/0/all/0/1">Joshua N. Winn</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jenkins_J/0/1/0/all/0/1">Jon M. Jenkins</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Anderson_D/0/1/0/all/0/1">David. R. Anderson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Barclay_T/0/1/0/all/0/1">Thomas Barclay</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bouchy_F/0/1/0/all/0/1">Fran&#xe7;ois Bouchy</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Burt_J/0/1/0/all/0/1">Jennifer A. Burt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Butler_R/0/1/0/all/0/1">R. Paul Butler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Caldwell_D/0/1/0/all/0/1">Douglas A. Caldwell</a>,Read More →

CTCV J2056-3014: An X-ray-faint Intermediate Polar Harboring An Extremely Fast-spinning White Dwarf. (arXiv:2007.13932v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Oliveira_R/0/1/0/all/0/1">Raimundo Lopes de Oliveira</a> (1,2), <a href="http://arxiv.org/find/astro-ph/1/au:+Bruch_A/0/1/0/all/0/1">Albert Bruch</a> (3) <a href="http://arxiv.org/find/astro-ph/1/au:+Rodrigues_%2E/0/1/0/all/0/1">. Claudia Vilega Rodrigues</a> (4), <a href="http://arxiv.org/find/astro-ph/1/au:+Oliveira_A/0/1/0/all/0/1">Alexandre Soares de Oliveira</a> (5), <a href="http://arxiv.org/find/astro-ph/1/au:+Mukai_K/0/1/0/all/0/1">Koji Mukai</a> (6,7)- ((1) UFS/Brazil, (2) ON/Brazil, (3) LNA/Brazil, (4) INPE/Brazil, (5) UNIVAP/Brazil, (6) NASA/USA, (7) UMBC/USA) We report on XMM-Newton X-ray observations that reveal CTCV J2056-3014 to be an unusual accretion-powered, intermediate polar (IP) system. It is a member of the class of X-ray-faint IPs whose space density remains unconstrained but potentially very high, with L$_{x,0.3-12 keV}$ of 1.8$times$10$^{31}$ erg s$^{-1}$. We discovered a coherent 29.6s pulsationRead More →

Dispersion measures of fast radio burst host galaxies derived from IllustrisTNG simulation. (arXiv:2007.13935v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Zhang_G/0/1/0/all/0/1">G. Q. Zhang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yu_H/0/1/0/all/0/1">Hai Yu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+He_J/0/1/0/all/0/1">J. H. He</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_F/0/1/0/all/0/1">F. Y. Wang</a> (NJU) We calculate the dispersion measures (DMs) contributed by host galaxies of fast radio bursts (FRBs). Based on a few host galaxy observations, a large sample of galaxy with similar properties to observed ones has been selected from the IllustrisTNG simulation. They are used to compute the distributions of host galaxy DMs for repeating and non-repeating FRBs. For repeating FRBs, we infer the DM$ _{mathrm{host}} $ for FRBs like FRB 121102 and FRB 180916 by assumingRead More →

Magnetic field fluctuations in anisotropic, supersonic turbulence. (arXiv:2007.13937v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Beattie_J/0/1/0/all/0/1">James R. Beattie</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Federrath_C/0/1/0/all/0/1">Christoph Federrath</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Seta_A/0/1/0/all/0/1">Amit Seta</a> The rich structure that we observe in molecular clouds is due to the interplay between strong magnetic fields and supersonic (turbulent) velocity fluctuations. The velocity fluctuations interact with the magnetic field, causing it too to fluctuate. Using numerical simulations, we explore the nature of such magnetic field fluctuations, $vec{delta B}$, over a wide range of turbulent Mach numbers, $mathcal{M} = 2 – 10$ (i.e., from weak to strong compressibility), and Alfv’en Mach numbers, $mathcal{M}_{text{A}0} = 0.1 – 100$ (i.e., from strong to weak magnetic mean fields,Read More →

Investigating the multiband nonthermal emission of the 100 TeV source eHWC J2019$+$368 with a pulsar wind nebula scenario. (arXiv:2007.13943v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Fang_J/0/1/0/all/0/1">Jun Fang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wen_L/0/1/0/all/0/1">Lu Wen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yu_H/0/1/0/all/0/1">Huan Yu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Songzhan_C/0/1/0/all/0/1">Chen Songzhan</a> eHWC J2019+368 is one of the sources emitting $gamma$-rays with energies higher than 100 TeV based on the recent measurement with the High Altitude Water Cherenkov Observatory (HAWC), and the origin is still in debate. The pulsar PSR J2021$+$3651 is spatially coincident with the TeV source. We investigate theoretically whether the multiband nonthermal emission of eHWC J2019+368 can originate from the pulsar wind nebula (PWN) G75.2$+$0.1 powered by PSR J2021$+$3651. In the model,Read More →

The Transient Jupiter Trojan-Like Orbit of P/2019 LD2 (ATLAS). (arXiv:2007.13945v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Hsieh_H/0/1/0/all/0/1">Henry H. Hsieh</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fitzsimmons_A/0/1/0/all/0/1">Alan Fitzsimmons</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Novakovic_B/0/1/0/all/0/1">Bojan Novakovic</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Denneau_L/0/1/0/all/0/1">Larry Denneau</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Heinze_A/0/1/0/all/0/1">Aren N. Heinze</a> Comet P/2019 LD2 has orbital elements currently resembling those of a Jupiter Trojan, and therefore superficially appears to represent a unique opportunity to study the volatile content and active behavior of a member of this population for the first time. However, numerical integrations show that it was previously a Centaur before reaching its current Jupiter Trojan-like orbit in 2018 July, and is expected to return to being a Centaur in 2028 February, before eventually becoming a Jupiter-familyRead More →

Modified gravity with disappearing cosmological constant. (arXiv:2007.13956v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Granda_L/0/1/0/all/0/1">L. N. Granda</a> New corrections to General Relativity are considered in the context of modified gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2Lambda$ at large curvature and tends to zero at $Rrightarrow 0$, containing flat spacetime solution and implying that the accelerated expansion is unrelated to quantum vacuum energy in flat space-time. The steepness of the deviation parameter $m$ at late times, for the analyzed models, leads to measurable signal of scalar-tensor regime in matter perturbations, that allows to detect departures form the $Lambda$CDM model. New corrections to GeneralRead More →

How Many Components? Quantifying the Complexity of the Metallicity Distribution in the Milky Way Bulge with APOGEE. (arXiv:2007.13967v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Rojas_Arriagada_A/0/1/0/all/0/1">A. Rojas-Arriagada</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zasowski_G/0/1/0/all/0/1">G. Zasowski</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schultheis_M/0/1/0/all/0/1">M. Schultheis</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zoccali_M/0/1/0/all/0/1">M. Zoccali</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hasselquist_S/0/1/0/all/0/1">S. Hasselquist</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chiappini_C/0/1/0/all/0/1">C. Chiappini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Cohen_R/0/1/0/all/0/1">R. E. Cohen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Cunha_K/0/1/0/all/0/1">K. Cunha</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fernandez_Trincado_J/0/1/0/all/0/1">J. G. Fern&#xe1;ndez-Trincado</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fragkoudi_F/0/1/0/all/0/1">F. Fragkoudi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Garcia_Hernandez_D/0/1/0/all/0/1">D. A. Garc&#xed;a-Hern&#xe1;ndez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Geisler_D/0/1/0/all/0/1">D. Geisler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lian_J/0/1/0/all/0/1">J. Lian</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Majewski_S/0/1/0/all/0/1">S. Majewski</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Minniti_D/0/1/0/all/0/1">D. Minniti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nitschelm_C/0/1/0/all/0/1">C. Nitschelm</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Queiroz_A/0/1/0/all/0/1">A. B. A. Queiroz</a> We use data of ~13.000 stars from the SDSS/APOGEE survey to study the shape of the MDF within the region $|l|leq11^circ$ and $|b|leq13^circ$, and spatially constrained to ${rm R_{GC}leq3.5}$~kpc. WeRead More →

Implications of Einstein-Maxwell dilaton-axion gravity from the black hole continuum spectrum. (arXiv:2007.13980v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Banerjee_I/0/1/0/all/0/1">Indrani Banerjee</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Mandal_B/0/1/0/all/0/1">Bhaswati Mandal</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+SenGupta_S/0/1/0/all/0/1">Soumitra SenGupta</a> String inspired models can serve as potential candidates to replace general relativity (GR) in the high energy regime where quantum gravity is expected to play a vital role. Such models not only subsume the ultraviolet nature of gravity but also exhibit promising prospects in addressing the dark sector, which cannot be adequately addressed within the framework of GR. The Einstein-Maxwell dilaton-axion (EMDA) theory, which is central to this work is one such string inspired model with interesting implications in inflationary cosmology and inRead More →

Starbursting Nuclei in Old Dwarf Galaxies. (arXiv:2007.13984v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Paudel_S/0/1/0/all/0/1">Sanjaya Paudel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yoon_S/0/1/0/all/0/1">Suk-Jin Yoon</a> Nuclei of early-type dwarf galaxies (dEs) are usually younger than the galaxy main body, and such discrepancy in age has been a puzzle. To explore the origin of young nuclei in dEs, we study a sample of dEs having compact star-forming blobs that are visually similar to dEs’ nuclei but by far bluer. We find that (1) the compact star-forming blobs have a typical stellar mass of one percent of the host galaxy stellar mass; (2) some of the blobs are positioned slightly off from the center of the galaxies; (3)Read More →