Search Publications
Ultradeep ATCA Imaging of 47 Tucanae Reveals a Central Compact Radio Source
Kamann, Sebastian; Dreizler, Stefan; Strader, Jay +9 more
We present the results of an ultradeep radio continuum survey, containing ~480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 µJy beam-1 at 5.5 GHz, 940 nJy beam-1 at 9 GHz,…
Variability of Blue Supergiants in the LMC with TESS
de Mink, Selma E.; Johnston, Cole; Ma, Linhao +1 more
The blue supergiant (BSG) problem, namely, the overabundance of BSGs inconsistent with classical stellar evolution theory, remains an open question in stellar astrophysics. Several theoretical explanations have been proposed, which may be tested by their predictions for the characteristic time variability. In this work, we analyze the light curves…
JWST Confirms the Nature of CID-42
Shen, Yue; Zhuang, Ming-Yang; Li, Junyao
The galaxy CID-42 (CXOC J100043.1+020637.2) at z = 0.359 has been proposed to contain a promising candidate for a gravitational-wave recoiling supermassive black hole (SMBH), a slingshot SMBH from a triple-SMBH interaction, or a kiloparsec-scale dual active galactic nucleus (AGN). These claims were primarily based on a pair of bright cores separat…
New Measurements of the Lyα Forest Continuum and Effective Optical Depth with LyCAN and DESI Y1 Data
Juneau, S.; Moustakas, J.; Brooks, D. +42 more
We present the Lyα Continuum Analysis Network (LyCAN), a convolutional neural network that predicts the unabsorbed quasar continuum within the rest-frame wavelength range of 1040–1600 Å based on the red side of the Lyα emission line (1216–1600 Å). We developed synthetic spectra based on a Gaussian mixture model representation of nonnegative matrix…
Chemical Diversity on Small Scales: Abundance Analysis of the Tucana V Ultrafaint Dwarf Galaxy
Li, Ting S.; Hansen, Terese T.; Simon, Joshua D. +5 more
The growing number of Milky Way satellites detected in recent years has introduced a new focus for stellar abundance analysis. Abundances of stars in satellites have been used to probe the nature of these systems and their chemical evolution. However, for most satellites, only centrally located stars have been examined. This paper presents an anal…
Hidden Gems on a Ring: Infant Massive Clusters and Their Formation Timeline Unveiled by ALMA, HST, and JWST in NGC 3351
Wilson, Christine D.; Bolatto, Alberto D.; Henshaw, Jonathan D. +38 more
We use 0.1″ observations from the Atacama Large Millimeter Array (ALMA), Hubble Space Telescope (HST), and JWST to study young massive clusters (YMCs) in their embedded "infant" phase across the central starburst ring in NGC 3351. Our new ALMA data reveal 18 bright and compact (sub-)millimeter continuum sources, of which 8 have counterparts in JWS…
Measuring the Milky Way Vertical Potential with the Phase Snail in a Model-independent Way
Mao, Shude; Liu, Chao; Shen, Juntai +2 more
The vertical phase-space spiral (snail) is a direct sign of disequilibrium of the Milky Way's disk. Nevertheless, the wrapping of the phase snail contains information on the vertical potential. We propose a novel method to measure the vertical potential utilizing the intersections between the snail and z/V z axes, for which we know th…
Signatures of Tidal Disruption of the Hercules Ultrafaint Dwarf Galaxy
Erkal, Denis; Geha, Marla; Frebel, Anna +6 more
The Hercules ultrafaint dwarf galaxy (UFD) has long been hypothesized to be tidally disrupting, yet no conclusive evidence has been found for tidal disruption owing partly to difficulties in identifying Hercules member stars. In this work, we present a homogeneous reanalysis of new and existing observations of Hercules, including the detection of …
AT 2023lli: A Tidal Disruption Event with Prominent Optical Early Bump and Delayed Episodic X-Ray Emission
Liu, Hao; Liu, Wei; Kong, Xu +42 more
High-cadence, multiwavelength observations have continuously revealed the diversity of tidal disruption events (TDEs), thus greatly advancing our knowledge and understanding of TDEs. In this work, we conducted an intensive optical-UV and X-ray follow-up campaign of TDE AT 2023lli and found a remarkable month-long bump in its UV/optical light curve…
FRESCO: The Paschen-α Star-forming Sequence at Cosmic Noon
Maseda, Michael V.; van Dokkum, Pieter; Reddy, Naveen A. +17 more
We present results from the JWST First Reionization Epoch Spectroscopically Complete Observations survey on the star-forming sequence (SFS) of galaxies at 1.0 < z < 1.7, around the peak of the cosmic star formation history. Star formation rates (SFRs) are measured from the redshifted, relatively dust-insensitive Paschen-α emission line, and …