9 papers
The Stellar Initial Mass Function down to 0.16M Towards the Small Magellanic Cloud
Roger E. Cohen, Mario Gennaro, Matteo Correnti +2
The presence (and nature) of variations in the stellar initial mass function (IMF) at substantially sub-solar masses and metallicities (0.5M, [M/H]1) r…
The JWST Resolved Stellar Populations Early Release Science Program. IX. The RR Lyrae Population in WLM with HST and JWST
Catherine M. Slaughter, Evan D. Skillman, Alessandro Savino +16
RR Lyrae stars are a common, dependable Population II distance indicator, and provide an independent tracer of early star formation. Here, we utilize archival HST/ACS and JWST/NIRC…
On the Use of Field RR Lyrae as Galactic Probes -- VIII. Early Formation of the Galactic Spheroid
G. Bono, V. F. Braga, M. Fabrizio +54
We introduce a new photometric catalog of RR Lyrae variables (RRLs, 300,000) mainly based on data available in public datasets. We also present the largest and most homogeneo…
The Proper Motion of Draco II with HST using Multiple Reference Frames and Methodologies
Jack T. Warfield, Kevin A. McKinnon, Sangmo Tony Sohn +13
We present proper motion (PM) measurements for Draco II, an ultra-faint dwarf satellite of the Milky Way. These PMs are measured using two epochs of Hubble Space Telescope Advanced…
Wide binaries in an ultra-faint dwarf galaxy: discovery, population modeling, and a nail in the coffin of primordial black hole dark matter
Cheyanne Shariat, Kareem El-Badry, Mario Gennaro +24
We report the discovery and characterization of a wide binary population in the ultrafaint dwarf galaxy Boötes I using deep JWST/NIRCam imaging. Our sample consists of 52 candidat…
A Low Metallicity Massive Contact Binary Star System Candidate in WLM identified by Hubble and James Webb Space Telescope imaging
Maude Gull, Daniel R. Weisz, Kareem El-Badry +15
We present archival HST and JWST ultraviolet through near infrared time series photometric observations of a massive minimal-contact binary candidate in the metal-poor galaxy WLM (…