Search Publications
The Herschel Exploitation of Local Galaxy Andromeda (HELGA). II. Dust and Gas in Andromeda
Blommaert, J. A. D. L.; Clements, D. L.; Boquien, M. +27 more
We present an analysis of the dust and gas in Andromeda, using Herschel images sampling the entire far-infrared peak. We fit a modified-blackbody model to ~4000 quasi-independent pixels with spatial resolution of ~140 pc and find that a variable dust-emissivity index (β) is required to fit the data. We find no significant long-wavelength excess ab…
Cosmic Microwave Background Constraints on the Duration and Timing of Reionization from the South Pole Telescope
Doré, O.; Bleem, L. E.; Stark, A. A. +48 more
The epoch of reionization is a milestone of cosmological structure formation, marking the birth of the first objects massive enough to yield large numbers of ionizing photons. However, the mechanism and timescale of reionization remain largely unknown. Measurements of the cosmic microwave background (CMB) Doppler effect from ionizing bubbles embed…
The CFHTLS-Strong Lensing Legacy Survey (SL2S): Investigating the Group-scale Lenses with the SARCS Sample
Kneib, J. -P.; Alard, C.; Gavazzi, R. +5 more
We present the Strong Lensing Legacy Survey-ARCS (SARCS) sample compiled from the final T0006 data release of the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) covering a total non-overlapping area of 159 deg2. We adopt a semi-automatic method to find gravitational arcs in the survey that makes use of an arc-finding algorithm. T…
The Star Formation Rate Function for Redshift z ~ 4-7 Galaxies: Evidence for a Uniform Buildup of Star-forming Galaxies during the First 3 Gyr of Cosmic Time
van Dokkum, Pieter G.; Franx, Marijn; Illingworth, Garth D. +4 more
We combine recent estimates of dust extinction at z ~ 4-7 with UV luminosity function (LF) determinations to derive star formation rate (SFR) functions at z ~ 4-7. SFR functions provide a more physical description of galaxy buildup at high redshift and allow for direct comparisons to SFRs at lower redshifts determined by a variety of techniques. O…
HST-COS Observations of AGNs. I. Ultraviolet Composite Spectra of the Ionizing Continuum and Emission Lines
Shull, J. Michael; Danforth, Charles W.; Stevans, Matthew
The ionizing fluxes from quasars and other active galactic nuclei (AGNs) are critical for interpreting the emission-line spectra of AGNs and for photoionization and heating of the intergalactic medium. Using ultraviolet spectra from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST), we have directly measured the rest-frame …
The Nature of Double-peaked [O III] Active Galactic Nuclei
Djorgovski, S. G.; Myers, Adam D.; Aldering, G. +4 more
Active galactic nuclei (AGNs) with double-peaked [O III] lines are suspected to be sub-kpc or kpc-scale binary AGNs. However, pure gas kinematics can produce the same double-peaked line profile in spatially integrated spectra. Here we combine integral-field spectroscopy and high-resolution imaging of 42 double-peaked [O III] AGNs from the Sloan Di…
Polarimetric Imaging of Large Cavity Structures in the Pre-transitional Protoplanetary Disk around PDS 70: Observations of the Disk
Kuzuhara, M.; Tamura, M.; Ishii, M. +52 more
We present high-resolution H-band polarized intensity (FWHM = 0farcs1: 14 AU) and L'-band imaging data (FWHM = 0farcs11: 15 AU) of the circumstellar disk around the weak-lined T Tauri star PDS 70 in Centaurus at a radial distance of 28 AU (0farcs2) up to 210 AU (1farcs5). In both images, a giant inner gap is clearly resolved for the first time, an…
IDCS J1426.5+3508: Discovery of a Massive, Infrared-selected Galaxy Cluster at z = 1.75
Dey, Arjun; Gonzalez, Anthony H.; Stanford, S. A. +6 more
We report the discovery of an IR-selected massive galaxy cluster in the IRAC Deep Cluster Survey (IDCS). We present new data from the Hubble Space Telescope and the W. M. Keck Observatory that spectroscopically confirm IDCS J1426.5+3508 at z = 1.75. Moreover, the cluster is detected in archival Chandra data as an extended X-ray source, comprising …
On the Detection of Ionizing Radiation Arising from Star-forming Galaxies at Redshift z ~ 3-4: Looking for Analogs of "Stellar Re-ionizers"
Castellano, Marco; Dickinson, Mark; Ferguson, Henry C. +15 more
We use the spatially resolved, multi-band photometry in the GOODS South field acquired by the CANDELS project to constrain the nature of candidate Lyman continuum (LyC) emitters at redshift z ~ 3.7 identified using ultradeep imaging below the Lyman limit (1σ limit of ≈30 AB in a 2'' diameter aperture). In 19 candidates out of a sample of 20 with f…
The Properties and Prevalence of Galactic Outflows at z ~ 1 in the Extended Groth Strip
Martin, Crystal L.; Shapley, Alice E.; Coil, Alison L. +5 more
We investigate galactic-scale outflowing winds in 72 star-forming galaxies at z ~ 1 in the Extended Groth Strip. Galaxies were selected from the DEEP2 survey and follow-up LRIS spectroscopy was obtained covering Si II, C IV, Fe II, Mg II, and Mg I lines in the rest-frame ultraviolet. Using Galaxy Evolution Explorer (GALEX), Hubble Space Telescope …