Search Publications
Supermassive Black Holes in Galactic Nuclei: Past, Present and Future Research
Ford, Holland; Ferrarese, Laura
This review discusses the current status of supermassive black hole research, as seen from a purely observational standpoint. Since the early ‘90s, rapid technological advances, most notably the launch of the Hubble Space Telescope, the commissioning of the VLBA and improvements in near-infrared speckle imaging techniques, have not only given us i…
Passively Evolving Early-Type Galaxies at 1.4 <~ z <~ 2.5 in the Hubble Ultra Deep Field
Cimatti, A.; Daddi, E.; Panagia, N. +13 more
We report on a complete sample of seven luminous early-type galaxies in the Hubble Ultra Deep Field (UDF) with spectroscopic redshifts between 1.39 and 2.47, and to KAB<23. Using the BzK selection criterion, we have preselected a set of objects over the UDF, which fulfill the photometric conditions for being passively evolving galaxi…
The Relationship between Luminosity and Broad-Line Region Size in Active Galactic Nuclei
Kaspi, Shai; Peterson, Bradley M.; Maoz, Dan +3 more
We reinvestigate the relationship between the characteristic broad-line region size (RBLR) and the Balmer emission-line, X-ray, UV, and optical continuum luminosities. Our study makes use of the best available determinations of RBLR for a large number of active galactic nuclei (AGNs) from Peterson et al. Using their determina…
Evolution of the Solar Activity over Time and Effects on Planetary Atmospheres. I. High-Energy Irradiances (1-1700 Å)
Güdel, Manuel; Guinan, Edward F.; Audard, Marc +1 more
We report on the results of the Sun in Time multiwavelength program (X-rays to UV) of solar analogs with ages covering ~0.1-7 Gyr. The chief science goals are to study the solar magnetic dynamo and to determine the radiative and magnetic properties of the Sun during its evolution across the main sequence. The present paper focuses on the latter go…
Resolved Massive Star Clusters in the Milky Way and Its Satellites: Brightness Profiles and a Catalog of Fundamental Parameters
van der Marel, Roeland P.; McLaughlin, Dean E.
We present a database of structural and dynamical properties for 153 spatially resolved star clusters in the Milky Way, the Large and Small Magellanic Clouds, and the Fornax dwarf spheroidal. This database complements and extends others in the literature, such as those of Harris and Mackey & Gilmore. Our cluster sample comprises 50 ``young mas…
Spitzer View on the Evolution of Star-forming Galaxies from z = 0 to z ~ 3
Papovich, Casey; Pérez-González, Pablo G.; Rieke, George H. +11 more
We use a 24 µm-selected sample containing more than 8000 sources to study the evolution of star-forming galaxies in the redshift range from z=0 to z~3. We obtain photometric redshifts for most of the sources in our survey using a method based on empirically built templates spanning from ultraviolet to mid-infrared wavelengths. The accuracy o…
Optimization of Starburst99 for Intermediate-Age and Old Stellar Populations
Leitherer, Claus; Vázquez, Gerardo A.
We have incorporated the latest release of the Padova models into the evolutionary synthesis code Starburst99. The Padova tracks were extended to include the full asymptotic giant branch (AGB) evolution until the final thermal pulse over the mass range 0.9-5 Msolar. With this addition, Starburst99 accounts for all stellar phases that co…
The afterglow of GRB 050709 and the nature of the short-hard γ-ray bursts
Cenko, S. B.; Peterson, B. A.; Price, P. A. +33 more
The final chapter in the long-standing mystery of the γ-ray bursts (GRBs) centres on the origin of the short-hard class of bursts, which are suspected on theoretical grounds to result from the coalescence of neutron-star or black-hole binary systems. Numerous searches for the afterglows of short-hard bursts have been made, galvanized by the revolu…
Toward an Understanding of the Rapid Decline of the Cosmic Star Formation Rate
Papovich, Casey; Pérez-González, Pablo G.; Bell, Eric F. +11 more
We present a first analysis of deep 24 µm observations with the Spitzer Space Telescope of a sample of nearly 1500 galaxies in a thin redshift slice, 0.65<=z<0.75. We combine the infrared data with redshifts, rest-frame luminosities, and colors from COMBO-17 and with morphologies from Hubble Space Telescope images collected by the Gala…
The Gemini Deep Deep Survey. VII. The Redshift Evolution of the Mass-Metallicity Relation
Juneau, S.; Glazebrook, K.; Abraham, R. G. +10 more
We have investigated the mass-metallicity (M-Z) relation using galaxies at 0.4<z<1.0 from the Gemini Deep Deep Survey (GDDS) and Canada-France Redshift Survey (CFRS). Deep K- and z'-band photometry allowed us to measure stellar masses for 69 galaxies. From a subsample of 56 galaxies, for which metallicity of the interstellar mediu…