Search Publications
Time Evolution Images of the Hypergiant RW Cephei during the Rebrightening Phase Following the Great Dimming
Gies, Douglas R.; Mérand, Antoine; Monnier, John D. +17 more
Stars with initial masses larger than 8 M ⊙ undergo substantial mass loss through mechanisms that remain elusive. Unraveling the origins of this mass loss is important for comprehending the evolutionary path of these stars, the type of supernova explosion, and whether they become neutron stars or black hole remnants. In 2022 December, R…
Thermal Properties of the Hot Core Population in Sagittarius B2 Deep South.
Schilke, P.; Battersby, C.; Ginsburg, A. +7 more
We report the discovery of nine new hot molecular cores in the Deep South (DS) region of Sagittarius B2 using Atacama Large Millimeter/submillimeter Array Band 6 observations. We measure the rotational temperature of CH3OH and derive the physical conditions present within these cores and the hot core Sgr B2(S). The cores show heterogene…
Constraints on Remnant Planetary Systems as a Function of Main-sequence Mass with HST/COS
Hermes, J. J.; Redfield, Seth; Tremblay, P. -E. +8 more
As the descendants of stars with masses less than 8 M ⊙ on the main sequence, white dwarfs provide a unique way to constrain planetary occurrence around intermediate-mass stars (spectral types BAF) that are otherwise difficult to measure with radial-velocity or transit surveys. We update the analysis of more than 250 ultraviolet spectra…
The Gasing Pangkah Collaboration. I. Asteroseismic Identification and Characterization of a Rapidly Rotating Engulfment Candidate
Lewis, Geraint F.; van Saders, Jennifer; Ong, J. M. Joel +19 more
We report the discovery and characterization of TIC 350842552 ("Zvrk"), an apparently isolated, rapidly rotating (P rot ∼ 99 days) red giant observed by TESS in its southern Continuous Viewing Zone. The star's fast surface rotation is independently verified by the use of p-mode asteroseismology, strong periodicity in TESS and ASAS-SN ph…
The Sun Remains Relatively Refractory Depleted: Elemental Abundances for 17,412 Gaia RVS Solar Analogs and 50 Planet Hosts
Rampalli, Rayna; Bedell, Megan; Ness, Melissa K. +2 more
The element abundances of stars, particularly the refractory elements (e.g., Fe, Si, and Mg), play an important role in connecting stars to their planets. Most Sun-like stars do not have refractory abundance measurements since obtaining a large sample of high-resolution spectra is difficult with oversubscribed observing resources. In this work we …
CORINOS. II. JWST-MIRI Detection of Warm Molecular Gas from an Embedded, Disk-bearing Protostar
Bergner, Jennifer B.; van Dishoeck, Ewine F.; Evans, Neal J. +8 more
We present James Webb Space Telescope (JWST) Mid-InfraRed Instrument (MIRI) observations of warm CO and H2O gas in emission toward the low-mass protostar IRAS 15398-3359, observed as part of the CORINOS program. The CO is detected via the rovibrational fundamental band and hot band near 5 µm, whereas the H2O is detected…
Discovery of the Longest-period Classical Cepheid in the Milky Way
Soszyński, I.; Udalski, A.; Szymański, M. K. +12 more
We report the discovery of the classical Cepheid OGLE-GD-CEP-1884 (= GDS_J1535467-555656) with the longest pulsation period known in our Galaxy. The period of 78.14 days is nearly 10 days longer than that of the previous record-holding Cepheid, S Vulpeculae, and thus, OGLE-GD-CEP-1884 can be categorized as the first ultra-long-period Cepheid in th…
Magnetic Fields in M-dwarf Members of the Pleiades Open Cluster Using APOGEE Spectra
Wanderley, Fábio; Cunha, Katia; Smith, Verne V. +10 more
Average magnetic field measurements are presented for 62 M-dwarf members of the Pleiades open cluster, derived from Zeeman-enhanced Fe I lines in the H band. A Markov Chain Monte Carlo methodology was employed to model magnetic filling factors using Sloan Digital Sky Survey (SDSS) IV APOGEE high-resolution spectra, along with the radiative transfe…
Dark Photon Dark Matter and Low-frequency Gravitational-wave Detection with Gaia-like Astrometry
Wang, Xin; Zhao, Yue; An, Haipeng +3 more
Astrometric surveys offer us a method for searching for elusive cosmic signatures, such as ultralight dark photon dark matter and gravitational waves (GWs), by observing the temporal change of stars' apparent locations. The detection capabilities of such surveys rapidly decrease at low frequencies, because the signals become hardly distinguishable…
Blowing Star Formation Away in Active Galactic Nuclei Hosts. I. Observation of Warm Molecular Outflows with JWST MIRI
Riffel, Rogério; Zakamska, Nadia L.; Storchi-Bergmann, Thaisa +4 more
We use the James Webb Space Telescope Mid-Infrared Instrument medium-resolution spectrometer observations of the radio-loud active galactic nucleus (AGN) host UGC 8782 to map the warm molecular and ionized gas kinematics. The data reveal spatially resolved outflows in the inner 2 kpc, seen in low ionization (traced by the [Ar II] 6.99 µm emi…