Search Publications
Galactic Mass Estimates Using Dwarf Galaxies as Kinematic Tracers
Eadie, Gwendolyn; Slizewski, Anika; Dufresne, Xander +4 more
New mass estimates and cumulative mass profiles with Bayesian credible regions for the Milky Way (MW) are found using the Galactic Mass Estimator (GME) code and dwarf galaxy (DG) kinematic data from multiple sources. GME takes a hierarchical Bayesian approach to simultaneously estimate the true positions and velocities of the DGs, their velocity a…
Kinematic Structure of the Large Magellanic Cloud Globular Cluster System from Gaia eDR3 and Hubble Space Telescope Proper Motions
van der Marel, Roeland P.; Alfaro-Cuello, Mayte; Watkins, Laura L. +3 more
We have determined bulk proper motions (PMs) for 31 LMC GCs from Gaia eDR3 and Hubble Space Telescope data using multiple independent analysis techniques. Combined with literature values for distances, line-of-sight velocities, and existing bulk PMs, we extract full 6D phase-space information for 32 clusters, allowing us to examine the kinematics …
Gaia 20eae: A Newly Discovered Episodically Accreting Young Star
Mahadevan, Suvrath; Wisniewski, John P.; Pandey, Rakesh +18 more
The Gaia Alert System issued an alert on 2020 August 28, on Gaia 20eae when its light curve showed a ~4.25 magnitude outburst. We present multiwavelength photometric and spectroscopic follow-up observations of this source since 2020 August and identify it as the newest member of the FUor/EXor family of sources. We find that the present brightening…
A fast radio burst progenitor born in a galaxy merger
Prochaska, J. Xavier; Kanekar, Nissim; Kaur, Balpreet
We report a Giant Metrewave Radio Telescope HI 21cm mapping study of the neutral atomic hydrogen (HI) in the host galaxy of the fast radio burst (FRB) FRB20180916B at z ≈ 0.03399. We find that the FRB host has an HI mass of MHI = (2.74 ± 0.33) × 109 M⊙ and a high HI-to-stellar mass ratio, ≈ 1.3. The FRB host is thu…
4FGL J1120.0-2204: A Unique Gamma-Ray-bright Neutron Star Binary with an Extremely Low-mass Proto-white Dwarf
Strader, Jay; Dage, Kristen C.; Chomiuk, Laura +5 more
We have discovered a new X-ray-emitting compact binary that is the likely counterpart to the unassociated Fermi-LAT GeV γ-ray source 4FGL J1120.0-2204, the second brightest Fermi source that still remains formally unidentified. Using optical spectroscopy with the SOAR telescope, we have identified a warm (T eff ~ 8500 K) companion in a …
High-energy Emission Component, Population, and Contribution to the Extragalactic Gamma-Ray Background of Gamma-Ray-emitting Radio Galaxies
Fukazawa, Yasushi; Inoue, Yoshiyuki; Matake, Hiroto +2 more
In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 Fermi Large Area Telescope detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy spectral component of radio galaxies, similar to blazars. With this sample, we also constructed a gamma-ray luminosity functi…
Spinning up the Surface: Evidence for Planetary Engulfment or Unexpected Angular Momentum Transport?
Reffert, Sabine; García, Rafael A.; Breton, Sylvain N. +15 more
In this paper, we report the potential detection of a nonmonotonic radial rotation profile in a low-mass lower-luminosity giant star. For most low- and intermediate-mass stars, the rotation on the main sequence seems to be close to rigid. As these stars evolve into giants, the core contracts and the envelope expands, which should suggest a radial …
Revealing the Nature of a Lyα Halo in a Strongly Lensed Interacting System at z = 2.92
Rigby, Jane R.; Sharon, Keren; Infante, Leopoldo +12 more
Spatially extended halos of H I Lyα emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative transfer effects of the Lyα line and limited angular resolution. In this paper, we present resolved Multi Unit Spec…
Two Candidate KH 15D-like Systems from the Zwicky Transient Facility
Fang, Min; Zang, Weicheng; Dong, Subo +8 more
KH 15D contains a circumbinary disk that is tilted relative to the orbital plane of the central binary. The precession of the disk and the orbital motion of the binary together produce rich phenomena in the photometric light curve. In this work, we present the discovery and preliminary analysis of two objects that resemble the key features of KH 1…
The Rapidly Evolving Asymptotic Giant Branch Star, V Hya: ALMA Finds a Multiring Circus with High-velocity Outflows
Sahai, R.; Morris, M. R.; Lee, C. -F. +3 more
We have observed the mass-losing carbon star V Hya that is apparently transitioning from an asymptotic giant branch star to a bipolar planetary nebula, at an unprecedented angular resolution of ~0.″4-0.″6 with the Atacama Large Millimeter/submillimeter Array. Our 13CO and 12CO (J = 3-2 and J = 2-1) images have led to the disc…