Search Publications
Star Formation Rates and Stellar Masses of z = 7-8 Galaxies from IRAC Observations of the WFC3/IR Early Release Science and the HUDF Fields
Trenti, M.; Oesch, P. A.; Carollo, C. M. +9 more
We investigate the Spitzer/IRAC properties of 36 z ~ 7 z 850-dropout galaxies and three z ~ 8 Y 098 galaxies derived from deep/wide-area WFC3/IR data of the Early Release Science, the ultradeep HUDF09, and wide-area NICMOS data. We fit stellar population synthesis models to the spectral energy distributions to derive mean red…
On the physical properties of z ≈ 6-8 galaxies
Schaerer, D.; de Barros, S.
Aims: We analyse the spectral energy distributions (SEDs) of the most distant galaxies discovered with the Hubble Space telescope and from the COSMOS survey and determine their physical properties, such as stellar age and mass, dust attenuation, and star-formation rate.
Methods: We use our SED fitting tool including the effects of nebula…
Anomalously low solar extreme-ultraviolet irradiance and thermospheric density during solar minimum
Woods, Thomas N.; Didkovsky, Leonid V.; Solomon, Stanley C. +2 more
Solar activity during 2007-2009 was very low, and during this protracted solar minimum period, the terrestrial thermosphere was cooler and lower in density than expected. Measurements from instruments on the SOHO and TIMED spacecraft, and by suborbital rocket flights, indicate that solar extreme-ultraviolet irradiance levels were lower than they w…
Accretion dynamics and disk evolution in NGC 2264: a study based on CoRoT photometric observations
Aigrain, S.; Bouvier, J.; Teixeira, P. S. +6 more
Context. The young cluster NGC 2264 was observed with the CoRoT satellite for 23 days uninterruptedly in March 2008 with unprecedented photometric accuracy. We present the first results of our analysis of the accreting population belonging to the cluster as observed by CoRoT.
Aims: We search for possible light curve variability of the same na…
A Herschel PACS and SPIRE study of the dust content of the Cassiopeia A supernova remnant
Ivison, R. J.; Olofsson, G.; Henning, Th. +13 more
Using the 3.5-m Herschel Space Observatory, imaging photometry of Cas A has been obtained in six bands between 70 and 500 µm with the PACS and SPIRE instruments, with angular resolutions ranging from 6 to 37”. In the outer regions of the remnant the 70-µm PACS image resembles the 24-µm image Spitzer image, with the emission attri…
The Persistence of Cool Galactic Winds in High Stellar Mass Galaxies between z ~ 1.4 and ~1
Weiner, Benjamin J.; Martin, Crystal L.; Prochaska, J. Xavier +4 more
We present an analysis of the Mg II λλ2796, 2803 and Fe II λλ2586, 2600 absorption line profiles in co-added spectra of 468 galaxies at 0.7 < z < 1.5. The galaxy sample, drawn from the Team Keck Treasury Redshift Survey of the GOODS-N field, has a range in stellar mass (M *) comparable to that of the sample at z ~ 1.4 analyzed in …
The Nature of Starbursts. I. The Star Formation Histories of Eighteen Nearby Starburst Dwarf Galaxies
McQuinn, Kristen B. W.; Cannon, John M.; Skillman, Evan D. +7 more
We use archival Hubble Space Telescope observations of resolved stellar populations to derive the star formation histories (SFHs) of 18 nearby starburst dwarf galaxies. In this first paper, we present the observations, color-magnitude diagrams (CMDs), and the SFHs of the 18 starburst galaxies, based on a homogeneous approach to the data reduction,…
Spectral Evolution of the Extraordinary Type IIn Supernova 2006gy
Filippenko, Alexei V.; Foley, Ryan J.; Smith, Nathan +2 more
We present a detailed analysis of the extremely luminous and long-lasting Type IIn supernova (SN) 2006gy using spectra obtained between days 36 and 237 after explosion. We derive the temporal evolution of the effective temperature, radius, blast-wave and SN-ejecta expansion speeds, and bolometric luminosity, as well as the progenitor wind density …
The Rise and Fall of Passive Disk Galaxies: Morphological Evolution Along the Red Sequence Revealed by COSMOS
Koekemoer, Anton M.; Scarlata, Claudia; Ma, Chung-Pei +13 more
The increasing abundance of passive "red-sequence" galaxies since z ~ 1-2 is mirrored by a coincident rise in the number of galaxies with spheroidal morphologies. In this paper, however, we show in detail, that, the correspondence between galaxy morphology and color is not perfect, providing insight into the physical origin of this evolution. Usin…
On the Origin of the Extended Hα Filaments in Cooling Flow Clusters
Veilleux, Sylvain; Rupke, David S. N.; Mushotzky, Richard +1 more
We present a high spatial resolution Hα survey of 23 cooling flow clusters using the Maryland Magellan Tunable Filter, covering 1-2 orders of magnitude in cooling rate, dM/dt, temperature, and entropy. We find that 8/23 (35%) of our clusters have complex, filamentary morphologies at Hα, while an additional 7/23 (30%) have marginally extended or nu…