Search Publications
Chemodynamical Signatures of Bar Resonances in the Galactic Disk: Current Data and Future Prospects
Fragkoudi, Francesca; Wheeler, Adam; Ness, Melissa +2 more
The Galactic disk exhibits complex chemical and dynamical substructure thought to be induced by the bar, spiral arms, and satellites. Here, we explore the chemical signatures of bar resonances in action and velocity space, and characterize the differences between the signatures of corotation (CR) and higher-order resonances using test particle sim…
Binary Formation in the Orion Nebula Cluster: Exploring the Substellar Limit
Reiter, Megan; Meyer, Michael R.; De Furio, Matthew +3 more
We present results constraining the multiplicity of the very low mass stars and substellar objects in the Orion Nebula Cluster (ONC). Our sample covers primary masses 0.012-0.1 M ⊙ using archival Hubble Space Telescope data obtained with the Advanced Camera for Surveys using multiple filters. Studying the binary populations of clusters …
V606 Cen: A Newly Formed Massive Contact Binary in a Hierarchical Triple System
Zhang, J.; Qian, S. -B.; Liao, W. -P. +3 more
V606 Centauri (V606 Cen) is an early B-type close binary with an orbital period of 1.4950935 days, and its complete light curves are very difficult to observe on the ground. By analyzing the continuous light curve obtained by TESS, we found that it is a marginal contact binary with a very low fill-out factor of about 2%. The O - C diagram of V606 …
The HST Large Program on ω Centauri. V. Exploring the Ultracool Dwarf Population with Stellar Atmosphere and Evolutionary Modeling
Anderson, Jay; Salaris, Maurizio; Burgasser, Adam J. +5 more
Brown dwarfs can serve as both clocks and chemical tracers of the evolutionary history of the Milky Way due to their continuous cooling and high sensitivity of spectra to composition. We focus on brown dwarfs in globular clusters that host some of the oldest coeval populations in the galaxy. Currently, no brown dwarfs in globular clusters have bee…
Molecular Gas Reservoirs in Massive Quiescent Galaxies at z 0.7 Linked to Late-time Star Formation
Johnson, Benjamin D.; Bezanson, Rachel; Rieke, Marcia +6 more
We explore how the presence of detectable molecular gas depends on the inferred star formation histories (SFHs) in eight massive, quiescent galaxies at z ~ 0.7. Half of the sample have clear detections of molecular gas, traced by CO(2-1). We find that the molecular gas content is unrelated to the rate of star formation decline prior to the most re…
First Census of Gas-phase Metallicity Gradients of Star-forming Galaxies in Overdense Environments at Cosmic Noon
Teplitz, Harry I.; Fan, Xiaohui; Cai, Zheng +8 more
We report the first spatially resolved measurements of gas-phase metallicity radial gradients in star-forming galaxies in overdense environments at z ≳ 2. The spectroscopic data are acquired by the MAMMOTH-Grism survey, a Hubble Space Telescope (HST) cycle 28 medium program. This program is obtaining 45 orbits of WFC3/IR grism spectroscopy in the …
Detection of Intracluster Globular Clusters in the First JWST Images of the Gravitational Lens Cluster SMACS J0723.3-7327 at z = 0.39
Lee, Myung Gyoon; Jang, In Sung; Bae, Jang Ho
We present a survey of globular clusters (GCs) in the massive gravitational lens cluster SMACS J0723.3-7327 at z = 0.39 based on the early released JWST/NIRCam images. In the color-magnitude diagrams of the point sources, we clearly find a rich population of intracluster GCs that are spread over a wide area of the cluster. Their ages, considering …
Updated Photometry of the Yellow Supergiant Progenitor and Late-time Observations of the Type IIb Supernova SN 2016gkg
Kilpatrick, Charles D.; Coulter, David A.; Foley, Ryan J. +4 more
We present Hubble Space Telescope (HST) observations of the Type IIb supernova (SN) SN 2016gkg at 652, 1698, and 1795 days from explosion with the Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3). Comparing to pre-explosion imaging from 2001 obtained with the Wide Field Planetary Camera 2, we demonstrate that SN 2016gkg is now fain…
Solar Energetic Particles Produced during Two Fast Coronal Mass Ejections
Wang, Yuming; Guo, Jingnan; Li, Xiaolei +1 more
Two recent extremely fast coronal mass ejections (CMEs) are of particular interest. The first one originated from the southern hemisphere on 2021 October 28 and caused strong solar energetic particle (SEP) events over a wide longitude range from Earth, STEREO-A, to Mars. However, the other one, originating from the center of the Earth-viewed solar…
An Intensity Mapping Constraint on the CO-galaxy Cross-power Spectrum at Redshift 3
Marrone, Daniel P.; Keating, Garrett K.; Keenan, Ryan P.
The abundance of cold molecular gas plays a crucial role in models of galaxy evolution. While deep spectroscopic surveys of CO emission lines have been a primary tool for measuring this abundance, the difficulty of these observations has motivated alternative approaches to studying molecular gas content. One technique, line intensity mapping, seek…