Search Publications
Measurements of Water Surface Snow Lines in Classical Protoplanetary Disks
Zhang, Ke; Banzatti, Andrea; Najita, Joan R. +5 more
We present deep Herschel-PACS spectroscopy of far-infrared water lines from a sample of four protoplanetary disks around solar-mass stars, selected to have strong water emission at mid-infrared wavelengths. By combining the new Herschel spectra with archival Spitzer-IRS spectroscopy, we retrieve a parameterized radial surface water vapor distribut…
The MOSDEF Survey: Detection of [O III]λ4363 and the Direct-method Oxygen Abundance of a Star-forming Galaxy at z = 3.08
Siana, Brian; Shapley, Alice E.; Reddy, Naveen A. +8 more
We present measurements of the electron-temperature-based oxygen abundance for a highly star-forming galaxy at z = 3.08, COSMOS-1908. This is the highest redshift at which [O III]λ4363 has been detected and the first time that this line has been measured at z\gt 2. We estimate an oxygen abundance of 12+{log}({{O}}/{{H}})={8.00}-0.14
Bright Galaxies at Hubble’s Redshift Detection Frontier: Preliminary Results and Design from the Redshift z ~ 9-10 BoRG Pure-Parallel HST Survey
Shull, J. M.; Brammer, G.; Treu, T. +14 more
We present the first results and design from the redshift z ∼ 9-10 Brightest of the Reionizing Galaxies Hubble Space Telescope survey BoRG[z9-10], aimed at searching for intrinsically luminous unlensed galaxies during the first 700 Myr after the Big Bang. BoRG[z9-10] is the continuation of a multi-year pure-parallel near-IR and optical imaging cam…
Measurements of Non-thermal Line Widths in Solar Active Regions
Warren, Harry P.; Brooks, David H.
Spectral line widths are often observed to be larger than can be accounted for by thermal and instrumental broadening alone. This excess broadening is a key observational constraint for both nanoflare and wave dissipation models of coronal heating. Here we present a survey of non-thermal velocities measured in the high temperature loops (1-4 MK) o…
Late-time Photometry of Type Ia Supernova SN 2012cg Reveals the Radioactive Decay of 57 Co
Rest, Armin; Riess, Adam G.; Graur, Or +3 more
Seitenzahl et al. have predicted that roughly three years after its explosion, the light we receive from a Type Ia supernova (SN Ia) will come mostly from reprocessing of electrons and X-rays emitted by the radioactive decay chain 57Co → 57Fe, instead of positrons from the decay chain 56Co → 56Fe that do…
A 5 x 109 Msun Black Hole in NGC 1277 from Adaptive Optics Spectroscopy
Gebhardt, Karl; Richstone, Douglas O.; Husemann, Bernd +4 more
The nearby lenticular galaxy NGC 1277 is thought to host one of the largest black holes known, however the black hole mass measurement is based on low spatial resolution spectroscopy. In this paper, we present Gemini Near-infrared Integral Field Spectrometer observations assisted by adaptive optics. We map out the galaxy's stellar kinematics withi…
The Grism Lens-Amplified Survey from Space (GLASS). III. A Census of Lyα Emission at z ≳ 7 from HST Spectroscopy
Vulcani, B.; Hoag, A.; Bradač, M. +15 more
We present a census of Lyα emission at z≳ 7, utilizing deep near-infrared Hubble Space Telescope grism spectroscopy from the first six completed clusters of the Grism Lens-Amplified Survey from Space (GLASS). In 24/159 photometrically selected galaxies we detect emission lines consistent with Lyα in the GLASS spectra. Based on the distribution of …
Explosive Chromospheric Evaporation in a Circular-ribbon Flare
Guo, Y.; Li, D.; Ji, H. S. +3 more
In this paper, we report our multiwavelength observations of the C4.2 circular-ribbon flare in active region (AR) 12434 on 2015 October 16. The short-lived flare was associated with positive magnetic polarities and a negative polarity inside, as revealed by the photospheric line-of-sight magnetograms. Such a magnetic pattern is strongly indicative…
The Correlation between Metallicity and Debris Disk Mass
Rieke, George H.; Gáspár, András; Ballering, Nicholas
We find that the initial dust masses in planetary debris disks are correlated with the metallicities of their central stars. We compiled a large sample of systems, including Spitzer, the Herschel DUNES and DEBRIS surveys, and WISE debris disk candidates. We also merged 33 metallicity catalogs to provide homogeneous [Fe/H] and {σ }[{Fe/{…
Rest-frame Optical Emission Lines in z ∼ 3.5 Lyman-break-selected Galaxies: The Ubiquity of Unusually High [OIII]/Hβ Ratios at 2 Gyr
Oesch, P. A.; van Dokkum, P.; Illingworth, G. D. +6 more
We present K-band spectra of rest-frame optical emission lines for 24 star-forming galaxies at z ∼ 3.2-3.7 using MOSFIRE on the Keck I telescope. Strong rest-frame optical [O III] and Hβ emission lines were detected in 18 Lyman break galaxies (LBGs). The median flux ratio of [O III]λ5007 to Hβ is {5.1}-0.5+0.5. This is a fact…