Search Publications

Circumgalactic Mg II Emission from an Isotropic Starburst Galaxy Outflow Mapped by KCWI
DOI: 10.3847/1538-4357/abd4e0 Bibcode: 2021ApJ...909..151B

Hennawi, Joseph F.; Prochaska, J. Xavier; Coil, Alison L. +3 more

We present spatially resolved spectroscopy from the Keck Cosmic Web Imager (KCWI) of a star-forming galaxy at z = 0.6942, which shows emission from the Mg II λλ2796, 2803 doublet in the circumgalactic medium (CGM) extending ∼37 kpc at 3σ significance in individual spaxels (1σ detection limit 4.8 × 10-19 erg s-1 cm-2

2021 The Astrophysical Journal
eHST 78
Characterizing Extreme Emission-line Galaxies. I. A Four-zone Ionization Model for Very High-ionization Emission
DOI: 10.3847/1538-4357/ac141b Bibcode: 2021ApJ...922..170B

Skillman, Evan D.; Chisholm, John; Erb, Dawn K. +3 more

Stellar population models produce radiation fields that ionize oxygen up to O+2, defining the limit of standard H II region models (<54.9 eV). Yet, some extreme emission-line galaxies, or EELGs, have surprisingly strong emission originating from much higher ionization potentials. We present UV HST/COS and optical LBT/MODS spectra of …

2021 The Astrophysical Journal
eHST 76
Dissecting the Local Environment of FRB 190608 in the Spiral Arm of its Host Galaxy
DOI: 10.3847/1538-4357/ac2818 Bibcode: 2021ApJ...922..173C

Chittidi, Jay S.; Simha, Sunil; Mannings, Alexandra +15 more

We present a high-resolution analysis of the host galaxy of fast radio burst (FRB) 190608, an SB(r)c galaxy at z = 0.11778 (hereafter HG 190608), to dissect its local environment and its contributions to the FRB properties. Our Hubble Space Telescope Wide Field Camera 3 ultraviolet and visible light image reveals that the subarcsecond localization…

2021 The Astrophysical Journal
Gaia eHST 76
Turbulent Gas in Lensed Planck-selected Starbursts at z ∼ 1-3.5
DOI: 10.3847/1538-4357/abcc01 Bibcode: 2021ApJ...908...95H

Frayer, D. T.; Frye, B. L.; Jiménez-Andrade, E. F. +26 more

Dusty star-forming galaxies at high redshift (1 < z < 3) represent the most intense star-forming regions in the universe. Key aspects to these processes are the gas heating and cooling mechanisms, and although it is well known that these galaxies are gas-rich, little is known about the gas excitation conditions. Only a few detailed radiative…

2021 The Astrophysical Journal
Herschel 76
Elevated r-process Enrichment in Gaia Sausage and Sequoia
DOI: 10.3847/2041-8213/abdbb8 Bibcode: 2021ApJ...908L...8A

Myeong, G. C.; Kobayashi, Chiaki; Belokurov, Vasily +6 more

The Gaia Sausage (GS) and the Sequoia represent the major accretion events that formed the stellar halo of the Milky Way. A detailed chemical study of these main building blocks provides a pristine view of the early steps of the Galaxy's assembly. We present the results of the analysis of the UVES high-resolution spectroscopic observations at the …

2021 The Astrophysical Journal
Gaia 75
A Diversity of Wave-driven Presupernova Outbursts
DOI: 10.3847/1538-4357/abc87c Bibcode: 2021ApJ...906....3W

Fuller, Jim; Wu, Samantha

Many core-collapse supernova (SN) progenitors show indications of enhanced pre-SN mass loss and outbursts, some of which could be powered by wave energy transport within the progenitor star. Depending on the star's structure, convectively excited waves driven by late-stage nuclear burning can carry substantial energy from the core to the envelope,…

2021 The Astrophysical Journal
eHST 72
The Broadband Counterpart of the Short GRB 200522A at z = 0.5536: A Luminous Kilonova or a Collimated Outflow with a Reverse Shock?
DOI: 10.3847/1538-4357/abc74a Bibcode: 2021ApJ...906..127F

Berger, E.; Cucchiara, A.; Dong, Y. +20 more

We present the discovery of the radio afterglow and near-infrared (NIR) counterpart of the Swift short gamma-ray burst (GRB) GRB 200522A, located at a small projected offset of ≈1 kpc from the center of a young, star-forming host galaxy at z = 0.5536. The radio and X-ray luminosities of the afterglow are consistent with those of on-axis cosmologic…

2021 The Astrophysical Journal
eHST 72
On the Three-dimensional Structure of Local Molecular Clouds
DOI: 10.3847/1538-4357/ac1f96 Bibcode: 2021ApJ...919...35Z

Koch, Eric W.; Alves, João; Speagle, Joshua S. +9 more

We leverage the 1 pc spatial resolution of the Leike et al. three-dimensional (3D) dust map to characterize the 3D structure of nearby molecular clouds (d ≲ 400 pc). We start by "skeletonizing" the clouds in 3D volume density space to determine their "spines," which we project on the sky to constrain cloud distances with ≈1% uncertainty. For each …

2021 The Astrophysical Journal
Gaia 72
Probabilistic Association of Transients to their Hosts (PATH)
DOI: 10.3847/1538-4357/abe8d2 Bibcode: 2021ApJ...911...95A

Prochaska, J. Xavier; Deller, Adam T.; Tendulkar, Shriharsh P. +4 more

We introduce a new method to estimate the probability that an extragalactic transient source is associated with a candidate host galaxy. This approach relies solely on simple observables: sky coordinates and their uncertainties, galaxy fluxes, and angular sizes. The formalism invokes Bayes' rule to calculate the posterior probability $P\left({O}_{…

2021 The Astrophysical Journal
eHST 72
Early-time Light Curves of Type Ia Supernovae Observed with TESS
DOI: 10.3847/1538-4357/abcd42 Bibcode: 2021ApJ...908...51F

Pál, András; Kochanek, C. S.; Latham, David W. +19 more

We present the early-time light curves of Type Ia supernovae (SNe Ia) observed in the first six sectors of Transiting Exoplanet Survey Satellite (TESS) data. Ten of these SNe were discovered by ASAS-SN, seven by ATLAS, six by ZTF, and one by Gaia. For nine of these objects with sufficient dynamic range (>3.0 mag from detection to peak), we fit …

2021 The Astrophysical Journal
Gaia 71