Search Publications

Massive Dead Galaxies at z ∼ 2 with HST Grism Spectroscopy. I. Star Formation Histories and Metallicity Enrichment
DOI: 10.3847/1538-4357/ab1d53 Bibcode: 2019ApJ...877..141M

Vulcani, B.; Treu, T.; Jones, T. +7 more

Observations have revealed massive ({log}{M}* /{M}≳ 11) galaxies that were already dead when the universe was only ∼2 Gyr. Given the short time before these galaxies were quenched, their past histories and quenching mechanism(s) are of particular interest. In this paper, we study star formation histories (SFHs) of 24 massiv…

2019 The Astrophysical Journal
eHST 65
Highly Magnified Stars in Lensing Clusters: New Evidence in a Galaxy Lensed by MACS J0416.1-2403
DOI: 10.3847/1538-4357/ab2888 Bibcode: 2019ApJ...880...58K

Miralda-Escudé, Jordi; Frye, Brenda; Dai, Liang +2 more

We examine a caustic-straddling arc at z = 0.9397 in the field of the galaxy cluster MACS J0416.1-2403 (z = 0.397) using archival multiband Hubble Space Telescope images and show that its surface brightness exhibits anomalies that can be explained by a single highly magnified star undergoing microlensing. First, we show that the surface brightness…

2019 The Astrophysical Journal
eHST 65
A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S II]-deficiency
DOI: 10.3847/1538-4357/ab418f Bibcode: 2019ApJ...885...57W

Heckman, Timothy M.; Leitherer, Claus; Wang, Bingjie +3 more

The source responsible for the reionization of the universe is believed to be the population of star-forming galaxies at z ∼ 6 to 12. The biggest uncertainty concerns the fraction of Lyman-continuum photons that actually escape from the galaxies. In recent years, several relatively small samples of “leaky” galaxies have been discovered, and clues …

2019 The Astrophysical Journal
eHST 65
Merging Cluster Collaboration: A Panchromatic Atlas of Radio Relic Mergers
DOI: 10.3847/1538-4357/ab2f90 Bibcode: 2019ApJ...882...69G

Bradač, M.; Venturi, T.; Jee, M. J. +13 more

Golovich et al. present an optical imaging and spectroscopic survey of 29 radio relic merging galaxy clusters. In this paper, we study this survey to identify substructure and quantify the dynamics of the mergers. Using a combined photometric and spectroscopic approach, we identify the minimum number of substructures in each system to describe the…

2019 The Astrophysical Journal
XMM-Newton eHST 64
The Polycyclic Aromatic Hydrocarbon Mass Fraction on a 10 pc Scale in the Magellanic Clouds
DOI: 10.3847/1538-4357/ab16cf Bibcode: 2019ApJ...876...62C

Gordon, Karl D.; Bot, Caroline; Leroy, Adam K. +8 more

We present maps of the dust properties in the Small and Large Magellanic Clouds (SMC, LMC) from fitting Spitzer and Herschel observations with the Draine & Li dust model. We derive the abundance of the small carbonaceous grain (or polycyclic aromatic hydrocarbon; PAH) component. The global PAH fraction ({q}{{PAH}}, the fraction of t…

2019 The Astrophysical Journal
Herschel 64
ALMA 26 arcmin2 Survey of GOODS-S at 1 mm (ASAGAO): Near-infrared-dark Faint ALMA Sources
DOI: 10.3847/1538-4357/ab0d22 Bibcode: 2019ApJ...878...73Y

Ouchi, Masami; Fujimoto, Seiji; Tamura, Yoichi +21 more

We report detections of two 1.2 mm continuum sources (S 1.2 mm ∼ 0.6 mJy) without any counterparts in the deep H- and/or K-band image (i.e., K-band magnitude ≳26 mag). These near-infrared-dark faint millimeter sources are uncovered by ASAGAO, a deep and wide-field (≃26 arcmin2) Atacama Large Millimeter/submillimeter Array (AL…

2019 The Astrophysical Journal
Gaia eHST 64
The ALMA Discovery of the Rotating Disk and Fast Outflow of Cold Molecular Gas in NGC 1275
DOI: 10.3847/1538-4357/ab3e6e Bibcode: 2019ApJ...883..193N

Fukazawa, Y.; Nagai, H.; Onishi, K. +13 more

We present observations using the Atacama Large Millimeter/submillimeter Array of the CO(2-1), HCN(3-2), and HCO+(3-2) lines in the nearby radio galaxy/brightest cluster galaxy (BCG) NGC 1275 with a spatial resolution of ∼20 pc. In previous observations, the CO(2-1) emission was detected as radial filaments lying in the east-west direct…

2019 The Astrophysical Journal
eHST 64
The Evolution of the Quenching of Star Formation in Cluster Galaxies since z ∼ 1
DOI: 10.3847/1538-4357/ab14ee Bibcode: 2019ApJ...876...40P

Muzzin, A.; Wilson, G.; Yee, H. K. C. +2 more

We study the star-forming (SF) population of galaxies within a sample of 209 IR-selected galaxy clusters at 0.3 ≤ z ≤ 1.1 in the ELAIS-N1 and XMM-LSS fields, exploiting the first HSC-SSP data release. The large area and depth of these data allow us to analyze the dependence of the SF fraction, f SF, on stellar mass and environment separ…

2019 The Astrophysical Journal
eHST 64
Pulsating in Unison at Optical and X-Ray Energies: Simultaneous High Time Resolution Observations of the Transitional Millisecond Pulsar PSR J1023+0038
DOI: 10.3847/1538-4357/ab2fdf Bibcode: 2019ApJ...882..104P

Campana, S.; Stella, L.; Sanna, A. +22 more

PSR J1023+0038 is the first millisecond pulsar discovered to pulsate in the visible band; such a detection took place when the pulsar was surrounded by an accretion disk and also showed X-ray pulsations. We report on the first high time resolution observational campaign of this transitional pulsar in the disk state, using simultaneous observations…

2019 The Astrophysical Journal
XMM-Newton 63
Prevalence of SED Turndown among Classical Be Stars: Are All Be Stars Close Binaries?
DOI: 10.3847/1538-4357/ab48e7 Bibcode: 2019ApJ...885..147K

Hallinan, G.; Klement, Robert; Carciofi, A. C. +16 more

Rapid rotation is a fundamental characteristic of classical Be stars and a crucial property allowing for the formation of their circumstellar disks. Past evolution in a mass and angular momentum transferring binary system offers a plausible solution to how Be stars attained their fast rotation. Although the subdwarf remnants of mass donors in such…

2019 The Astrophysical Journal
AKARI Gaia 63