Search Publications
A Light-curve Analysis of the X-Ray Flash First Observed in Classical Novae
Kato, Mariko; Hachisu, Izumi; Saio, Hideyuki
An X-ray flash, expected in a very early phase of a nova outburst, was at last detected with the SRG/eROSITA in the classical nova YZ Reticuli 2020. The observed flash timescale, luminosity, and blackbody temperature substantially constrain the nova model. We present light-curve models of the X-ray flash for various white dwarf (WD) masses and mas…
Probability of Forming Gaps in the GD-1 Stream by Close Encounters of Globular Clusters
Hattori, Kohei; Doke, Yuka
One of the most intriguing properties of the GD-1 stellar stream is the existence of three gaps. If these gaps were formed by close encounters with dark matter subhalos, the GD-1 stream opens an exciting window through which we can see the size, mass, and velocity distributions of the dark matter subhalos in the Milky Way. However, in order to use…
HAZMAT. VIII. A Spectroscopic Analysis of the Ultraviolet Evolution of K Stars: Additional Evidence for K Dwarf Rotational Stalling in the First Gigayear
Loyd, R. O. Parke; Jackman, James A. G.; Barman, Travis +7 more
Efforts to discover and characterize habitable zone planets have primarily focused on Sun-like stars and M dwarfs. K stars, however, provide an appealing compromise between these two alternatives that has been relatively unexplored. Understanding the ultraviolet (UV) environment around such stars is critical to our understanding of their planets, …
DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy
Fielding, Drummond; Cameron, Alex J.; Kacprzak, Glenn G. +14 more
We compare 500 pc scale, resolved observations of ionized and molecular gas for the z ~ 0.02 starbursting disk galaxy IRAS08339+6517, using measurements from KCWI and NOEMA. We explore the relationship of the star-formation-driven ionized gas outflows with colocated galaxy properties. We find a roughly linear relationship between the outflow mass …
On the Formation of Solar Wind and Switchbacks, and Quiet Sun Heating
Tripathi, Durgesh; Upendran, Vishal
The solar coronal heating in quiet Sun (QS) and coronal holes (CHs), including solar wind formation, are intimately tied by magnetic field dynamics. Thus, a detailed comparative study of these regions is needed to understand the underlying physical processes. CHs are known to have subdued intensity and larger blueshifts in the corona. This work in…
Revisiting a Disky Origin for the Faint Branch of the Sagittarius Stellar Stream
Errani, Raphaël; Famaey, Benoit; Ibata, Rodrigo +2 more
We investigate ways to produce the bifurcation observed in the stellar stream of the Sagittarius dwarf galaxy (Sgr). Our method consists of running N-body simulations of Sgr falling into the Milky Way for the last 3 Gyr, with added test particles on disk orbits that span a wide range of initial positions, energies, and angular momenta. We find tha…
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…