Search Publications
Resolved Stellar Mass Maps of Galaxies in the Hubble Frontier Fields: Evidence for Mass Dependency in Environmental Quenching
Matharu, Jasleen; Muzzin, Adam; van der Wel, Arjen +9 more
One of the challenges in understanding the quenching processes for galaxies is connecting progenitor star-forming populations to their descendant quiescent populations over cosmic time. Here we attempt a novel approach to this challenge by assuming that the underlying stellar mass distribution of galaxies is not significantly altered during enviro…
IM Normae: The Death Spiral of a Cataclysmic Variable?
Myers, Gordon; Monard, Berto; Dvorak, Shawn +18 more
We present a study of the orbital light curves of the recurrent nova IM Normae since its 2002 outburst. The broad "eclipses" recur with a 2.46 hr period, which increases on a timescale of 1.28(16) × 106 yr. Under the assumption of conservative mass transfer, this suggests a rate near 10-7 M ⊙ yr-1, and t…
SRGA J181414.6-225604: A New Galactic Symbiotic X-Ray Binary Outburst Triggered by an Intense Mass-loss Episode of a Heavily Obscured Mira Variable
Soria, Roberto; Boyer, Martha L.; Conroy, Charlie +24 more
We present the discovery and multiwavelength characterization of SRGA J181414.6-225604, a Galactic hard X-ray transient discovered during the ongoing SRG/ART-XC sky survey. Using data from the Palomar Gattini-IR survey, we identify a spatially and temporally coincident variable infrared (IR) source, IRAS 18111-2257, and classify it as a very-late-…
A 16 hr Transit of Kepler-167 e Observed by the Ground-based Unistellar Telescope Network
Esposito, Thomas M.; Wagner, Kevin; Dalba, Paul A. +35 more
More than 5000 exoplanets have been confirmed and among them almost 4000 were discovered by the transit method. However, few transiting exoplanets have an orbital period greater than 100 days. Here we report a transit detection of Kepler-167 e, a "Jupiter analog" exoplanet orbiting a K4 star with a period of 1071 days, using the Unistellar ground-…
Radio Jet Proper-motion Analysis of Nine Distant Quasars above Redshift 3.5
Frey, Sándor; Gabányi, Krisztina Éva; An, Tao +2 more
Up to now, jet kinematic studies of radio quasars have barely reached beyond the redshift range z > 3.5. This significantly limits our knowledge of high-redshift jets, which can provide key information for understanding the jet nature and the growth of black holes in the early universe. In this paper, we selected nine radio-loud quasars at z &g…
A Quarter Century of Guitar Nebula/Filament Evolution
Kargaltsev, Oleg; Klingler, Noel; Slane, Patrick +6 more
We have collected a new deep Chandra X-Ray Observatory exposure of PSR B2224+65 and the "Guitar Nebula," mapping the complex X-ray structure. This is accompanied by a new Hubble Space Telescope (HST) Hα image of the head of the Guitar. Comparing the HST and Chandra structures in four epochs over 25 yr, we constrain the evolution of the TeV particl…
The Dark Matter Halo of M54
Grillmair, Carl J.; Carlberg, Raymond G.
M54 is a prototype for a globular cluster embedded in a dark matter halo. Gaia Early Data Release 3 photometry and proper motions separate the old, metal-poor stars from the more metal-rich and younger dwarf galaxy stars. The metal-poor stars dominate the inner 50 pc, with a velocity dispersion profile that declines to a minimum around 30 pc then …
LARS XIII: High Angular Resolution 21 cm H I Observations of Lyα Emitting Galaxies
Cannon, John M.; Hayes, Matthew; Östlin, Göran +8 more
The Lyα emission line is one of the main observables of galaxies at high redshift, but its output depends strongly on the neutral gas distribution and kinematics around the star-forming regions where UV photons are produced. We present observations of Lyα and 21 cm H I emission at comparable scales with the goal to qualitatively investigate how th…
Optical-Radio Position Offsets Are Inversely Correlated with AGN Photometric Variability
Secrest, Nathan J.
Using photometric variability information from the new Gaia DR3 release, I show for the first time that photometric variability is inversely correlated with the prevalence of optical-radio position offsets in the active galactic nuclei (AGNs) that comprise the International Celestial Reference Frame (ICRF). While the overall prevalence of statisti…
Connecting Low- and High-redshift Weak Emission-line Quasars via Hubble Space Telescope Spectroscopy of Lyα Emission
Brandt, W. N.; Anderson, Scott F.; Fan, Xiaohui +10 more
We present ultraviolet spectroscopy covering the Lyα + N V complex of six candidate low-redshift (0.9 < z < 1.5) weak emission-line quasars (WLQs) based on observations with the Hubble Space Telescope. The original systematic searches for these puzzling Type 1 quasars with intrinsically weak broad emission lines revealed an N ≈ 100 WLQ popul…