Search Publications

The MOSDEF Survey: A Census of AGN-driven Ionized Outflows at z = 1.4-3.8
DOI: 10.3847/1538-4357/ab4a7c Bibcode: 2019ApJ...886...11L

Siana, Brian; Azadi, Mojegan; Aird, James +13 more

Using data from the MOSFIRE Deep Evolution Field (MOSDEF) survey, we present a census of active galactic nucleus (AGN)-driven ionized outflows in a sample of 159 AGNs at 1.4 ≤ z ≤ 3.8. The sample spans AGN bolometric luminosities of 1044-47 erg s-1 and includes both quiescent and star-forming galaxies extending across 3 order…

2019 The Astrophysical Journal
eHST 70
Proper Motions of Stellar Streams Discovered in the Dark Energy Survey
DOI: 10.3847/1538-4357/ab44bf Bibcode: 2019ApJ...885....3S

Wang, M. Y.; Kuehn, K.; Li, T. S. +14 more

We cross-match high-precision astrometric data from Gaia DR2 with accurate multiband photometry from the Dark Energy Survey (DES) DR1 to confidently measure proper motions for nine stellar streams in the DES footprint: Aliqa Uma, ATLAS, Chenab, Elqui, Indus, Jhelum, Phoenix, Tucana III, and Turranburra. We determine low-confidence proper-motion me…

2019 The Astrophysical Journal
Gaia 69
Relative Alignment between the Magnetic Field and Molecular Gas Structure in the Vela C Giant Molecular Cloud Using Low- and High-density Tracers
DOI: 10.3847/1538-4357/ab1eb0 Bibcode: 2019ApJ...878..110F

Ward-Thompson, Derek; Fissel, Laura M.; Friesen, Rachel +37 more

We compare the magnetic field orientation for the young giant molecular cloud Vela C inferred from 500 µm polarization maps made with the BLASTPol balloon-borne polarimeter to the orientation of structures in the integrated line emission maps from Mopra observations. Averaging over the entire cloud we find that elongated structures in integr…

2019 The Astrophysical Journal
Gaia 69
Whistler Fan Instability Driven by Strahl Electrons in the Solar Wind
DOI: 10.3847/2041-8213/ab01bd Bibcode: 2019ApJ...871L..29V

Bale, S. D.; Krasnoselskikh, V.; Mozer, F. S. +3 more

We present a theoretical analysis of electron heat flux inhibition in the solar wind when a significant portion of the heat flux is carried by strahl electrons. We adopt core-strahl velocity distribution functions typical for the solar wind at 0.3-4 au to demonstrate that strahl electrons are capable of generating highly oblique whistler waves at …

2019 The Astrophysical Journal
Cluster 69
The Type II-plateau Supernova 2017eaw in NGC 6946 and Its Red Supergiant Progenitor
DOI: 10.3847/1538-4357/ab1136 Bibcode: 2019ApJ...875..136V

Van Dyk, Schuyler D.; Filippenko, Alexei V.; Kelly, Patrick L. +31 more

We present extensive optical photometric and spectroscopic observations, from 4 to 482 days after explosion, of the Type II-plateau (II-P) supernova (SN) 2017eaw in NGC 6946. SN 2017eaw is a normal SN II-P intermediate in properties between, for example, SN 1999em and SN 2012aw and the more luminous SN 2004et, also in NGC 6946. We have determined …

2019 The Astrophysical Journal
eHST 69
ALMA 200 pc Resolution Imaging of Smooth Cold Dusty Disks in Typical z ∼ 3 Star-forming Galaxies
DOI: 10.3847/1538-4357/ab3791 Bibcode: 2019ApJ...882..107R

Daddi, E.; Elbaz, D.; Franco, M. +14 more

We present high-fidelity, 30 mas (200 pc) resolution ALMA rest-frame 240 µm observations of cold dust emission in three typical main-sequence star-forming galaxies (SFGs) at z ∼ 3 in the Hubble Ultra-Deep Field (HUDF). The cold dust is distributed within the smooth disklike central regions of star formation 1-3 kpc in diameter, despite their…

2019 The Astrophysical Journal
eHST 69
Searching for Highly Magnified Stars at Cosmological Distances: Discovery of a Redshift 0.94 Blue Supergiant in Archival Images of the Galaxy Cluster MACS J0416.1-2403
DOI: 10.3847/1538-4357/ab297d Bibcode: 2019ApJ...881....8C

Filippenko, Alexei V.; Foley, Ryan J.; Kelly, Patrick L. +12 more

Individual highly magnified stars have been recently discovered at lookback times of more than half the age of the universe, in lensed galaxies that straddle the critical curves of massive galaxy clusters. Having established their detectability, it is now important to carry out systematic searches for them in order to establish their frequency, an…

2019 The Astrophysical Journal
eHST 68
CLEAR. I. Ages and Metallicities of Quiescent Galaxies at 1.0 < z < 1.8 Derived from Deep Hubble Space Telescope Grism Data
DOI: 10.3847/1538-4357/aaf22e Bibcode: 2019ApJ...870..133E

Papovich, Casey; Dickinson, Mark; Giavalisco, Mauro +14 more

We use deep Hubble Space Telescope spectroscopy to constrain the metallicities and (light-weighted) ages of massive ({log}{M}* /{M}≳ 10) galaxies selected to have quiescent stellar populations at 1.0 < z < 1.8. The data include twelve-orbit depth coverage with the WFC3/G102 grism covering ∼8000 < λ < 11,500 Å at…

2019 The Astrophysical Journal
eHST 68
Recovering Thermodynamics from Spectral Profiles observed by IRIS: A Machine and Deep Learning Approach
DOI: 10.3847/2041-8213/ab15d9 Bibcode: 2019ApJ...875L..18S

De Pontieu, Bart; Gošić, Milan; Sainz Dalda, Alberto +1 more

Inversion codes allow the reconstruction of a model atmosphere from observations. With the inclusion of optically thick lines that form in the solar chromosphere, such modeling is computationally very expensive because a non-LTE evaluation of the radiation field is required. In this study, we combine the results provided by these traditional metho…

2019 The Astrophysical Journal
IRIS 67
New Constraints From Dust Lines on the Surface Densities of Protoplanetary Disks
DOI: 10.3847/1538-4357/ab20ce Bibcode: 2019ApJ...878..116P

Murray-Clay, Ruth; Pérez, Laura M.; Powell, Diana +2 more

We present new determinations of disk surface density, independent of an assumed dust opacity, for a sample of seven bright, diverse, protoplanetary disks using measurements of disk dust lines. We develop a robust method for determining the location of dust lines by modeling disk interferometric visibilities at multiple wavelengths. The disks in o…

2019 The Astrophysical Journal
Gaia 67