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Water Vapor in the Spectrum of the Extrasolar Planet HD 189733b. II. The Eclipse
Deming, Drake; Madhusudhan, Nikku; Crouzet, Nicolas +1 more
Spectroscopic observations of exoplanets are crucial to infer the composition and properties of their atmospheres. HD 189733b is one of the most extensively studied exoplanets and is a cornerstone for hot Jupiter models. In this paper, we report the dayside emission spectrum of HD 189733b in the wavelength range 1.1-1.7 µm obtained with the …
Young Galaxy Candidates in the Hubble Frontier Fields. I. A2744
Broadhurst, Tom; Kelson, Daniel D.; Moustakas, John +10 more
We report the discovery of 24 Lyman-break candidates at 7 <~ z <~ 10.5, in the Hubble Frontier Fields (HFF) imaging data of A2744 (z = 0.308), plus Spitzer/IRAC data and archival ACS data. The sample includes a triple image system with a photometric redshift of z ~= 7.4. This high redshift is geometrically confirmed by our lens model corresp…
MOSFIRE Absorption Line Spectroscopy of z > 2 Quiescent Galaxies: Probing a Period of Rapid Size Growth
Ellis, Richard S.; Belli, Sirio; Newman, Andrew B. +1 more
Using the MOSFIRE near-infrared multi-slit spectrograph on the Keck 1 Telescope, we have secured high signal-to-noise ratio absorption line spectra for six massive galaxies with redshift 2 < z < 2.5. Five of these galaxies lie on the red sequence and show signatures of passive stellar populations in their rest-frame optical spectra. By fitti…
NuSTAR Unveils a Compton-thick Type 2 Quasar in Mrk 34
Harrison, F. A.; Stern, D.; Zhang, W. W. +27 more
We present Nuclear Spectroscopic Telescope Array (NuSTAR) 3-40 keV observations of the optically selected Type 2 quasar (QSO2) SDSS J1034+6001 or Mrk 34. The high-quality hard X-ray spectrum and archival XMM-Newton data can be fitted self-consistently with a reflection-dominated continuum and a strong Fe Kα fluorescence line with equivalent width …
The Angular Clustering of WISE-selected Active Galactic Nuclei: Different Halos for Obscured and Unobscured Active Galactic Nuclei
Stern, D.; Assef, R. J.; Yan, Lin +1 more
We calculate the angular correlation function for a sample of ~170,000 active galactic nuclei (AGNs) extracted from the Wide-field Infrared Survey Explorer (WISE) catalog, selected to have red mid-IR colors (W1 - W2 > 0.8) and 4.6 µm flux densities brighter than 0.14 mJy). The sample is expected to be >90% reliable at identifying AGNs …
A Survey for Hα Pulsar Bow Shocks
Romani, Roger W.; Brownsberger, Sasha
We report on a survey for Hα bow shock emission around nearby γ-detected energetic pulsars. This survey adds three Balmer-dominated neutron star bow shocks to the six previously confirmed examples. In addition to the shock around Fermi pulsar PSR J1741-2054, we now report Hα structures around two additional γ-ray pulsars, PSR J2030+4415 and PSR J1…
Detection of White Dwarf Companions to Blue Stragglers in the Open Cluster NGC 188: Direct Evidence for Recent Mass Transfer
Sills, Alison; Knigge, Christian; Leigh, Nathan +3 more
Several possible formation pathways for blue straggler stars have been developed recently, but no one pathway has yet been observationally confirmed for a specific blue straggler. Here we report the first findings from a Hubble Space Telescope Advanced Camera for Surveys/Solar Blind Channel far-UV photometric program to search for white dwarf comp…
Molecular Gas Heating Mechanisms, and Star Formation Feedback in Merger/Starbursts: NGC 6240 and Arp 193 as Case Studies
Greve, T. R.; van der Werf, Paul; Zhang, Zhi-Yu +6 more
We used the SPIRE/FTS instrument aboard the Herschel Space Observatory to obtain the Spectral Line Energy Distributions (SLEDs) of CO from J = 4-3 to J = 13-12 of Arp 193 and NGC 6240, two classical merger/starbursts selected from our molecular line survey of local Luminous Infrared Galaxies (L IR >= 1011 L ⊙). …
Three Ancient Halo Subgiants: Precise Parallaxes, Compositions, Ages, and Implications for Globular Clusters
Schaefer, Gail H.; Nelan, Edmund P.; Bond, Howard E. +3 more
The most accurate ages for the oldest stars are those obtained for nearby halo subgiants because they depend almost entirely on just the measured parallaxes and absolute oxygen abundances. In this study, we have used the Fine Guidance Sensors on the Hubble Space Telescope to determine trigonometric parallaxes, with precisions of 2.1% or better, fo…
Hubble Space Telescope/Advanced Camera for Surveys Confirmation of the Dark Substructure in A520
Hoekstra, H.; Jee, M. J.; Mahdavi, A. +1 more
We present a weak-lensing study of the cluster A520 based on Advanced Camera for Surveys (ACS) data. The excellent data quality provides a mean source density of ~109 arcmin-2, which improves both resolution and significance of the mass reconstruction compared to a previous study based on Wide Field Planetary Camera 2 (WFPC2) images. We…