Search Publications
LensWatch. I. Resolved HST Observations and Constraints on the Strongly Lensed Type Ia Supernova 2022qmx ("SN Zwicky")
Poidevin, F.; Shirley, R.; Marques-Chaves, R. +42 more
Supernovae (SNe) that have been multiply imaged by gravitational lensing are rare and powerful probes for cosmology. Each detection is an opportunity to develop the critical tools and methodologies needed as the sample of lensed SNe increases by orders of magnitude with the upcoming Vera C. Rubin Observatory and Nancy Grace Roman Space Telescope. …
PHANGS-JWST First Results: Dust-embedded Star Clusters in NGC 7496 Selected via 3.3 µm PAH Emission
Sandstrom, Karin M.; Kruijssen, J. M. Diederik; Leroy, Adam K. +38 more
The earliest stages of star formation occur enshrouded in dust and are not observable in the optical. Here we leverage the extraordinary new high-resolution infrared imaging from JWST to begin the study of dust-embedded star clusters in nearby galaxies throughout the Local Volume. We present a technique for identifying dust-embedded clusters in NG…
Early Planet Formation in Embedded Disks (eDisk). III. A First High-resolution View of Submillimeter Continuum and Molecular Line Emission toward the Class 0 Protostar L1527 IRS
Kwon, Woojin; Lai, Shih-Ping; Han, Ilseung +25 more
Studying the physical and chemical conditions of young embedded disks is crucial to constrain the initial conditions for planet formation. Here we present Atacama Large Millimeter/submillimeter Array observations of dust continuum at ~0.″06 (8 au) resolution and molecular line emission at ~0.″17 (24 au) resolution toward the Class 0 protostar L152…
Atmospheric Effects on Neutron Star Parameter Constraints with NICER
Bogdanov, Slavko; Salmi, Tuomo; Watts, Anna L. +7 more
We present an analysis of the effects of uncertainties in the atmosphere models on the radius, mass, and other neutron star parameter constraints for the NICER observations of rotation-powered millisecond pulsars. To date, NICER has applied the X-ray pulse profile modeling technique to two millisecond-period pulsars: PSR J0030+0451 and the high-ma…
A Swing of the Pendulum: The Chemodynamics of the Local Stellar Halo Indicate Contributions from Several Radial Merger Events
Donlon, Thomas; Newberg, Heidi Jo
We find that the chemical abundances and dynamics of APOGEE and GALAH stars in the local stellar halo are inconsistent with a scenario in which the inner halo is primarily composed of debris from a single massive, ancient merger event, as has been proposed to explain the Gaia-Enceladus/Gaia Sausage (GSE) structure. The data contain trends of chemi…
PHANGS-JWST First Results: Interstellar Medium Structure on the Turbulent Jeans Scale in Four Disk Galaxies Observed by JWST and the Atacama Large Millimeter/submillimeter Array
Sandstrom, Karin M.; van der Wel, Arjen; Henshaw, Jonathan D. +31 more
JWST/Mid-Infrared Instrument imaging of the nearby galaxies IC 5332, NGC 628, NGC 1365, and NGC 7496 from PHANGS reveals a richness of gas structures that in each case form a quasi-regular network of interconnected filaments, shells, and voids. We examine whether this multiscale network of structure is consistent with the fragmentation of the gas …
Early Results from GLASS-JWST. IX. First Spectroscopic Confirmation of Low-mass Quiescent Galaxies at z > 2 with NIRISS
Santini, Paola; Calabrò, Antonello; Castellano, Marco +20 more
How passive galaxies form, and the physical mechanisms which prevent star formation over long timescales, are some of the most outstanding questions in understanding galaxy evolution. The properties of quiescent galaxies over cosmic time provide crucial information to identify the quenching mechanisms. Passive galaxies have been confirmed and stud…
Gas-rich, Field Ultra-diffuse Galaxies Host Few Globular Clusters
Janowiecki, Steven; Sand, David J.; Leisman, Lukas +7 more
We present Hubble Space Telescope imaging of 14 gas-rich, low-surface-brightness galaxies in the field at distances of 25-36 Mpc, with mean effective radii and g-band central surface brightnesses of 1.9 kpc and 24.2 mag arcsec-2. Nine meet the standard criteria to be considered ultra-diffuse galaxies (UDGs). An inspection of point-like …
Mapping Protoplanetary Disk Vertical Structure with CO Isotopologue Line Emission
Wilner, David J.; Andrews, Sean M.; Bae, Jaehan +21 more
High-spatial-resolution observations of CO isotopologue line emission in protoplanetary disks at mid-inclinations (≈30°–75°) allow us to characterize the gas structure in detail, including radial and vertical substructures, emission surface heights and their dependencies on source characteristics, and disk temperature profiles. By combining observ…
Application of the Disk Instability Model to All Quasiperiodic Eruptions
Li, Shuang-Liang; Cao, Xinwu; Pan, Xin
After the first quasiperiodic eruption (QPE; GSN 069) was reported in 2019, four other sources have been identified as a QPE or a candidate. However, the physics behind QPEs is still unclear, although several models have been proposed. Pan et al. proposed an instability model for an accretion disk with magnetically driven outflows in the first QPE…