Search Publications
Correlations between Supermassive Black Holes, Velocity Dispersions, and Mass Deficits in Elliptical Galaxies with Cores
Kormendy, John; Bender, Ralf
High-dynamic-range surface photometry in a companion paper makes possible accurate measurement of the stellar light deficits L def and mass deficits M def associated with the cores of elliptical galaxies. We show that L def correlates with velocity dispersions σ of the host galaxy bulge averaged outside the central…
A Determination of the Spin of the Black Hole Primary in LMC X-1
Steiner, James F.; Remillard, Ronald A.; McClintock, Jeffrey E. +7 more
The first extragalactic X-ray binary, LMC X-1, was discovered in 1969. In the 1980s, its compact primary was established as the fourth dynamical black hole candidate. Recently, we published accurate values for the mass of the black hole and the orbital inclination angle of the binary system. Building on these results, we have analyzed 53 X-ray spe…
Abundant Circumstellar Silica Dust and SiO Gas Created by a Giant Hypervelocity Collision in the ~12 Myr HD172555 System
Bryden, G.; Wyatt, M. C.; Chen, C. H. +4 more
The fine dust detected by infrared (IR) emission around the nearby β Pic analog star HD172555 is very peculiar. The dust mineralogy is composed primarily of highly refractory, nonequilibrium materials, with approximately three quarters of the Si atoms in silica (SiO2) species. Tektite and obsidian lab thermal emission spectra (nonequili…
The COSMOS Active Galactic Nucleus Spectroscopic Survey. I. XMM-Newton Counterparts
Trump, Jonathan R.; McCarthy, Patrick J.; Comastri, Andrea +17 more
We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2 deg2 Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph…
Star Clusters in M31. I. A Catalog and a Study of the Young Clusters
Caldwell, Nelson; Harding, Paul; Rose, James A. +3 more
We present an updated catalog of 1300 objects in the field of M31, including 670 likely star clusters of various types, the rest being stars or background galaxies once thought to be clusters. The coordinates in the catalog are accurate to 0farcs2, and are based on images from the Local Group Survey (LGS) or from the Digitized Sky Survey (DSS). Ar…
Suzaku Observations of Abell 1795: Cluster Emission to r200
Miller, Eric D.; Sanders, Jeremy S.; Hughes, John P. +10 more
We report Suzaku observations of the galaxy cluster Abell 1795 that extend to r_200 ~ 2 Mpc, the radius within which the mean cluster mass density is 200 times the cosmic critical density. These observations are the first to probe the state of the intracluster medium in this object at r > 1.3 Mpc. We sample two disjoint sectors in the cluster o…
On the Nature of the Prototype Luminous Blue Variable Ag Carinae. I. Fundamental Parameters During Visual Minimum Phases and Changes in the Bolometric Luminosity During the S-Dor Cycle
Hillier, D. J.; Rossi, C.; Whitelock, P. A. +3 more
We present a detailed spectroscopic analysis of the luminous blue variable (LBV) AG Carinae (AG Car) during the last two visual minimum phases of its S-Dor cycle (1985-1990 and 2000-2003). The analysis reveals an overabundance of He, N, and Na, and a depletion of H, C, and O, on the surface of the AG Car, indicating the presence of a CNO-processed…
An Intermediate Luminosity Transient in NGC 300: The Eruption of a Dust-Enshrouded Massive Star
Berger, E.; Fransson, C.; Chevalier, R. A. +10 more
We present multi-epoch high-resolution optical spectroscopy, UV/radio/X-ray imaging, and archival Hubble and Spitzer observations of an intermediate luminosity optical transient recently discovered in the nearby galaxy NGC 300. We find that the transient (NGC 300 OT2008-1) has a peak absolute magnitude of M bol ≈ -11.8 mag, intermediate…
An Estimate of the Chemical Composition of Titan's Lakes
Mousis, Olivier; Lunine, Jonathan I.; Lavvas, Panayotis +2 more
Hundreds of radar-dark patches interpreted as lakes have been discovered in the north and south polar regions of Titan. We have estimated the composition of these lakes by using the direct abundance measurements from the Gas Chromatograph Mass Spectrometer aboard the Huygens probe and recent photochemical models based on the vertical temperature p…
Fresh Insights on the Structure of the Solar Core
Chaplin, William J.; Basu, Sarbani; Serenelli, Aldo M. +2 more
We present new results on the structure of the solar core, obtained with new sets of frequencies of solar low-degree p modes obtained from the BiSON network. We find that different methods used in extracting the different sets of frequencies cause shifts in frequencies, but the shifts are not large enough to affect solar structure results. We find…