Search Publications
Observational Evidence for Enhanced Black Hole Accretion in Giant Elliptical Galaxies
McNamara, Brian R.; Hickox, Ryan C.; Kara, Erin +5 more
We present a study of the relationship between black hole accretion rate (BHAR) and star formation rate (SFR) in a sample of giant elliptical galaxies. These galaxies, which live at the centers of galaxy groups and clusters, have star formation and black hole activity that is primarily fueled by gas condensing out of the hot intracluster medium. F…
A Broadband View on Microquasar MAXI J1820+070 during the 2018 Outburst
Tramacere, A.; Fiocchi, M.; Ubertini, P. +5 more
The microquasar MAXI J1820+070 went into outburst from 2018 mid-March until mid-July, with several faint rebrightenings afterward. With a peak flux of approximately 4 Crab in the 20-50 keV energy range, the source was monitored across the electromagnetic spectrum with detections from radio to hard X-ray frequencies. Using these multiwavelength obs…
TOI-942b: A Prograde Neptune in a 60 Myr Old Multi-transiting System
Latham, David W.; Quinn, Samuel N.; Zhou, George +8 more
Mapping the orbital obliquity distribution of young planets is one avenue toward understanding mechanisms that sculpt the architectures of planetary systems. TOI-942 is a young field star, with an age of ~60 Myr, hosting a planetary system consisting of two transiting Neptune-sized planets in 4.3 and 10.1 day period orbits. We observed the spectro…
Discovery of a Highly Neutronized Ejecta Clump in the Type Ia Supernova Remnant 3C 397
Petre, Robert; Sato, Toshiki; Yamaguchi, Hiroya +7 more
The supernova remnant (SNR) 3C 397 is thought to originate from a Type Ia supernova (SN Ia) explosion of a near-Chandrasekhar-mass (MCh) progenitor, based on the enhanced abundances of Mn and Ni revealed by previous X-ray study with Suzaku. Here we report follow-up XMM-Newton observations of this SNR, conducted with the aim of investiga…
A New Reconstruction of the Sun's Magnetic Field and Total Irradiance since 1700
Wang, Y. -M.; Lean, J. L.
We model the Sun's large-scale magnetic field and total solar irradiance (TSI) since 1700 by combining flux transport simulations with empirical relationships between facular brightening, sunspot darkening, and the total photospheric flux. The photospheric field is evolved subject to the constraints that (1) the flux emergence rate scales as the y…
Discovery of the 5 keV Cyclotron Line Followed by Three Harmonics in Swift J1626.6-5156
Tsygankov, S.; Santangelo, A.; Lutovinov, A. +4 more
We report on observations of the Be/X-ray binary system Swift J1626.6-5156 performed with the Nuclear Spectroscopic Telescope ARray (NuSTAR) during a short outburst in 2021 March, following its detection by the MAXI monitor and Spektrum-Roentgen-Gamma (SRG) observatory. Our analysis of the broadband X-ray spectrum of the source confirms the presen…
The New Magnetar SGR J1830-0645 in Outburst
Tiengo, A.; Rea, N.; Esposito, P. +13 more
The detection of a short hard X-ray burst and an associated bright soft X-ray source by the Swift satellite in 2020 October heralded a new magnetar in outburst, SGR J1830-0645. Pulsations at a period of ∼10.4 s were detected in prompt follow-up X-ray observations. We present here the analysis of the Swift/Burst Alert Telescope burst, of XMM-Newton…
Coronal Heating and Solar Wind Formation in Quiet Sun and Coronal Holes: A Unified Scenario
Solanki, Sami K.; Tripathi, Durgesh; Nived, V. N.
Coronal holes (CHs) are darker than the quiet Sun (QS) when observed in coronal channels. This study aims to understand the similarities and differences between CHs and QS in the transition region using the Si IV 1394 Å line, recorded by the Interface Region Imaging Spectrograph, by considering the distribution of magnetic field measured by the He…
A Blueprint for the Milky Way's Stellar Populations. II. Improved Isochrone Calibration in the SDSS and Pan-STARRS Photometric Systems
Beers, Timothy C.; An, Deokkeun
We improve the identification and isolation of individual stellar populations in the Galactic halo based on an updated set of empirically calibrated stellar isochrones in the Sloan Digital Sky Survey and Pan-STARRS 1 photometric systems. Along the Galactic prime meridian (l = 0° and 180°), where proper motions and parallaxes from Gaia DR2 can be u…
The Cosmic Ultraviolet Baryon Survey (CUBS). II. Discovery of an H2-bearing DLA in the Vicinity of an Early-type Galaxy at z = 0.576
Faucher-Giguère, Claude-André; Johnson, Sean D.; Petitjean, Patrick +18 more
We report the serendipitous detection of an H2-bearing damped Lyα absorber at z = 0.576 in the spectrum of the QSO J0111-0316 in the Cosmic Ultraviolet Baryon Survey. Spectroscopic observations from Hubble Space Telescope-COS in the far-ultraviolet reveal a damped absorber with log[N(H I)/cm-2] = 20.1 ± 0.2 and log[N(H2<…