Search Publications
Near-infrared Spectroscopy of Galaxies During Reionization: Measuring C III] in a Galaxy at z = 7.5
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +9 more
We present Keck/MOSFIRE H-band spectroscopy targeting C III] λ1907, 1909 in a z = 7.5056 galaxy previously identified via Lyα emission. We detect strong line emission at 1.621+/- 0.002 µ {{m}} with a line flux of (2.63 ± 0.52) × 10-18 erg s-1 cm-2. We tentatively identify this line as [C III] λ1907, but we ar…
Molecular and Ionized Gas Phases of an AGN-driven Outflow in a Typical Massive Galaxy at z ≈ 2
Lutz, D.; Wuyts, S.; Genzel, R. +22 more
Nuclear outflows driven by accreting massive black holes are one of the main feedback mechanisms invoked at high-z to reproduce the distinct separation between star-forming disk galaxies and quiescent spheroidal systems. Yet our knowledge of feedback at high-z remains limited by the lack of observations of the multiple gas phases in galaxy outflow…
First Resolution of Microlensed Images
Kochanek, C. S.; Gould, Andrew; Stanek, K. Z. +12 more
We employ Very Large Telescope Interferometer GRAVITY to resolve, for the first time, the two images generated by a gravitational microlens. The measurements of the image separation {{Δ }}{θ }-,+=3.78+/- 0.05 mas, and hence the Einstein radius θ E = 1.87 ± 0.03 mas, are precise. This demonstrates the robustness of the method,…
The MOSDEF Survey: A Census of AGN-driven Ionized Outflows at z = 1.4-3.8
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…
Proper Motions of Stellar Streams Discovered in the Dark Energy Survey
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…
Relative Alignment between the Magnetic Field and Molecular Gas Structure in the Vela C Giant Molecular Cloud Using Low- and High-density Tracers
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…
Whistler Fan Instability Driven by Strahl Electrons in the Solar Wind
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 …
The Type II-plateau Supernova 2017eaw in NGC 6946 and Its Red Supergiant Progenitor
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 …
ALMA 200 pc Resolution Imaging of Smooth Cold Dusty Disks in Typical z ∼ 3 Star-forming Galaxies
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…
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
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…