Search Publications
VODKA-JWST: A 3.8 kpc Dual Quasar at Cosmic Noon in a Powerful Starburst Galaxy with JWST/MIRI Integral Field Unit
Shen, Yue; Veilleux, Sylvain; Zakamska, Nadia L. +12 more
Dual quasars—two active supermassive black holes at galactic scales—represent crucial objects for studying the impact of galaxy mergers and quasar activity on the star formation rate (SFR) within their host galaxies, particularly at cosmic noon when SFR peaks. We present JWST/MIRI mid-infrared integral field spectroscopy of J074922.96+225511.7, a …
WIYN Open Cluster Study. XC. Barium Surface Abundances of Blue Straggler Stars in the Open Clusters NGC 7789 and M67
Schuler, Simon C.; Mathieu, Robert D.; Nine, Andrew C. +1 more
We investigate barium (Ba) abundances in blue straggler stars (BSSs) in two open clusters, NGC 7789 (1.6 Gyr) and M67 (4 Gyr), as signatures of asymptotic-giant-branch (AGB) mass transfer. We combine our findings with previous Ba abundance analyses of NGC 6819 (2.5 Gyr) and NGC 188 (7 Gyr). Out of 35 BSSs studied in NGC 7789, NGC 6819, and M67, 15…
Spectroscopic Observations of Coronal Rain Formation and Evolution Following an X2 Solar Flare
Warren, Harry P.; Ugarte-Urra, Ignacio; Brooks, David H. +2 more
A significant impediment to solving the coronal heating problem is that we currently only observe active region loops in their cooling phase. Previous studies showed that the evolution of cooling loop densities and apex temperatures is insensitive to the magnitude, duration, and location of energy deposition. Still, potential clues to how energy i…
A First Look with JWST Aperture Masking Interferometry: Resolving Circumstellar Dust around the Wolf–Rayet Binary WR 137 beyond the Rayleigh Limit
Corcoran, Michael F.; Morris, Mark R.; Russell, Christopher M. P. +20 more
We present infrared aperture-masking interferometry (AMI) observations of newly formed dust from the colliding winds of the massive binary Wolf–Rayet system WR 137 with JWST using the Near Infrared Imager and Slitless Spectrograph (NIRISS). NIRISS AMI observations of WR 137 and a point-spread function calibrator star, HD 228337, were taken using t…
Goodbye to Chi by Eye: A Bayesian Analysis of Photometric Binaries in Six Open Clusters
von Hippel, Ted; Motherway, Erin; Geller, Aaron M. +2 more
We present a robust methodology for identifying photometric binaries in star clusters. Using Gaia DR3, Pan-STARRS, and Two Micron All Sky Survey data, we self-consistently define the cluster parameters and binary demographics for the open clusters (OCs) NGC 2168 (M35), NGC 7789, NGC 6819, NGC 2682 (M67), NGC 188, and NGC 6791. These clusters span …
TEMPLATES: Direct Abundance Constraints for Two Lensed Lyman-break Galaxies
Hutchison, Taylor A.; Mahler, Guillaume; Rigby, Jane R. +20 more
Using integrated spectra for two gravitationally lensed galaxies from the JWST TEMPLATES Early Release Science program, we analyze faint auroral lines, which provide direct measurements of the gas-phase chemical abundance. For the brighter galaxy, SGAS1723+34 (z = 1.3293), we detect the [O III] λ4363, [S III] λ6312, and [O II] λ λ7320, 7330 aurora…
Ultraviolet and Chromospheric Activity and Habitability of M Stars
Huang, Yang; Liu, Jifeng; Wang, Song +4 more
M-type stars are crucial for stellar activity studies because they cover two types of magnetic dynamos and are particularly intriguing for habitability studies due to their abundance and long lifespans during the main-sequence stage. In this paper, we used the LAMOST DR9 catalog and the GALEX UV archive data to investigate the chromospheric and UV…
Determining Cosmological-model-independent H 0 with Gravitationally Lensed Supernova Refsdal
Li, Xiaolei; Liao, Kai
The reappearance of supernova Refsdal with detailed modeling of the lens cluster allows us to measure the time-delay distance, which serves as a powerful tool to determine the Hubble constant (H 0). We give a cosmological-model-independent method to estimate H 0 through Gaussian process regression, using time-delay measuremen…
Stellar Models are Reliable at Low Metallicity: An Asteroseismic Age for the Ancient Very Metal-poor Star KIC 8144907
Li, Yaguang; Huber, Daniel; Ong, J. M. Joel +15 more
Very-metal-poor stars ([Fe/H] < ‑2) are important laboratories for testing stellar models and reconstructing the formation history of our galaxy. Asteroseismology is a powerful tool to probe stellar interiors and measure ages, but few asteroseismic detections are known in very-metal-poor stars and none have allowed detailed modeling of oscillat…
Scylla. II. The Spatially Resolved Star Formation History of the Large Magellanic Cloud Reveals an Inverted Radial Age Gradient
McQuinn, Kristen B. W.; Dolphin, Andrew E.; Murray, Claire E. +11 more
The proximity of the Magellanic Clouds provides the opportunity to study interacting dwarf galaxies near a massive host, and spatial trends in their stellar population properties in particular, with a unique level of detail. The Scylla pure parallel program has obtained deep (80% complete to >1 mag below the ancient main-sequence turnoff), homo…