Search Publications
The Brightest Gamma-Ray Flaring Blazar in the Sky: AGILE and Multi-wavelength Observations of 3C 454.3 During 2010 November
Maraschi, L.; Sakamoto, T.; Pian, E. +84 more
Since 2005, the blazar 3C 454.3 has shown remarkable flaring activity at all frequencies, and during the last four years it has exhibited more than one γ-ray flare per year, becoming the most active γ-ray blazar in the sky. We present for the first time the multi-wavelength AGILE, Swift, INTEGRAL, and GASP-WEBT data collected in order to explain t…
SMA Observations of GOODS 850-11 and GOODS 850-13: First Examples of Multiple Submillimeter Sources Resolved by an Interferometer
Williams, Jonathan P.; Wang, Wei-Hao; Cowie, Lennox L. +1 more
We carried out extremely sensitive Submillimeter Array (SMA) 340 GHz continuum imaging on two submillimeter galaxies (SMGs): GOODS 850-11 and GOODS 850-13. The observations reach sub-mJy rms sensitivities and, interestingly, resolve both sources into multiple, physically unrelated SMGs. GOODS 850-11 is resolved into two sources at different redshi…
Detection of the Cosmic Far-infrared Background in AKARI Deep Field South
Clements, D. L.; White, G. J.; Burgarella, D. +14 more
We report new limits on the absolute brightness and spatial fluctuations of the cosmic infrared background (CIB) via the AKARI satellite. We carried out observations at 65, 90, 140, and 160 µm as a cosmological survey in AKARI Deep Field South, which is one of the lowest cirrus regions with a contiguous area of the sky. After removing bright…
The Host Galaxies of Low-mass Black Holes
Ho, Luis C.; Barth, Aaron J.; Greene, Jenny E. +2 more
Using Hubble Space Telescope observations of 147 host galaxies of low-mass black holes (BHs), we systematically study the structures and scaling relations of these active galaxies. Our sample is selected to have central BHs with virial masses of ~105-106 M ⊙. The host galaxies have total I-band magnitudes of -23.2 …
Redshift Evolution of the Galaxy Velocity Dispersion Function
Brinchmann, Jarle; van Dokkum, Pieter G.; Franx, Marijn +9 more
We present a study of the evolution of the galaxy velocity dispersion function (VDF) from z = 0 to z = 1.5 using photometric data from the Ultra-Deep and the NEWFIRM Medium-Band Survey in the COSMOS field. The VDF has been measured locally using direct kinematic measurements from the Sloan Digital Sky Survey (SDSS), but direct studies of the VDF a…
Population Parameters of Intermediate-age Star Clusters in the Large Magellanic Cloud. II. New Insights from Extended Main-sequence Turnoffs in Seven Star Clusters
Chandar, Rupali; Goudfrooij, Paul; Puzia, Thomas H. +1 more
We discuss new photometry from high-resolution images of seven intermediate-age (1-2 Gyr) star clusters in the Large Magellanic Cloud taken with the Advanced Camera for Surveys on board the Hubble Space Telescope. We fit color-magnitude diagrams (CMDs) with several different sets of theoretical isochrones and determine systematic uncertainties for…
The Globular Cluster NGC 2419: A Crucible for Theories of Gravity
Dalessandro, E.; Bellazzini, M.; Chapman, S. C. +3 more
We present the analysis of a kinematic data set of stars in the globular cluster NGC 2419, taken with the DEep Imaging Multi-Object Spectrograph at the Keck II telescope. Combined with a reanalysis of deep Hubble Space Telescope and Subaru Telescope imaging data, which provide an accurate luminosity profile of the cluster, we investigate the valid…
AEGIS: Demographics of X-ray and Optically Selected Active Galactic Nuclei
Koekemoer, Anton M.; Weiner, Benjamin J.; Nandra, Kirpal +19 more
We develop a new diagnostic method to classify galaxies into active galactic nucleus (AGN) hosts, star-forming galaxies, and absorption-dominated galaxies by combining the [O III]/Hβ ratio with rest-frame U - B color. This can be used to robustly select AGNs in galaxy samples at intermediate redshifts (z < 1). We compare the result of this opti…
Quantitative Examination of a Large Sample of Supra-arcade Downflows in Eruptive Solar Flares
Savage, Sabrina L.; McKenzie, David E.
Sunward-flowing voids above post-coronal mass ejection flare arcades were first discovered using the soft X-ray telescope aboard Yohkoh and have since been observed with TRACE (extreme ultraviolet (EUV)), SOHO/LASCO (white light), SOHO/SUMER (EUV spectra), and Hinode/XRT (soft X-rays). Supra-arcade downflow (SAD) observations suggest that they are…
Probing Very Bright End of Galaxy Luminosity Function at z >~ 7 Using Hubble Space Telescope Pure Parallel Observations
Koekemoer, Anton M.; Fan, Xiaohui; McCarthy, Patrick J. +8 more
We report the first results from the Hubble Infrared Pure Parallel Imaging Extragalactic Survey, which utilizes the pure parallel orbits of the Hubble Space Telescope to do deep imaging along a large number of random sightlines. To date, our analysis includes 26 widely separated fields observed by the Wide Field Camera 3, which amounts to 122.8 ar…