Search Publications
The Centers of Early-Type Galaxies with Hubble Space Telescope. VI. Bimodal Central Surface Brightness Profiles
Filippenko, Alexei V.; Ho, Luis C.; Gebhardt, Karl +9 more
We combine several HST investigations on the central structure of early-type galaxies to generate a large sample of surface photometry. The studies selected were those that used the ``Nuker law'' to characterize the inner light distributions of the galaxies. The sample comprises WFPC1 and WFPC2 V-band observations published earlier by our group, R…
A Log-Quadratic Relation for Predicting Supermassive Black Hole Masses from the Host Bulge Sérsic Index
Graham, Alister W.; Driver, Simon P.
We reinvestigate the correlation between black hole mass and bulge concentration. With an increased galaxy sample (totaling 27) and updated estimates of galaxy distances, black hole masses, and Sérsic indices n-a measure of concentration-we perform a least-squares regression analysis to obtain a relation suitable for the purpose of predicting blac…
The Stellar Mass Tully-Fisher Relation to z = 1.2 from AEGIS
Weiner, Benjamin J.; Faber, S. M.; Lotz, Jennifer M. +12 more
We combine newly measured rotation velocities, velocity dispersions, and stellar masses to construct stellar mass Tully-Fisher relations (M*TFRs) for 544 galaxies with strong emission lines at 0.1<z<1.2 from the All-Wavelength Extended Groth Strip International Survey (AEGIS) and the Deep Extragalactic Evolutionary Probe 2 (DEEP2)…
Quiet-Sun Internetwork Magnetic Fields from the Inversion of Hinode Measurements
Lites, B. W.; Ichimoto, K.; Bellot Rubio, L. R. +10 more
We analyze Fe I 630 nm observations of the quiet Sun at disk center taken with the spectropolarimeter of the Solar Optical Telescope aboard the Hinode satellite. A significant fraction of the scanned area, including granules, turns out to be covered by magnetic fields. We derive field strength and inclination probability density functions from a M…
The Inner Jet of the Radio Galaxy M87
Kellermann, K. I.; Kovalev, Y. Y.; Lister, M. L. +1 more
We report new 2 cm VLBA images of the inner radio jet of M87 showing a limb-brightened structure and unambiguous evidence for a faint 3 mas long counterfeature which also appears limb brightened. Multiepoch observations of seven separate jet features show typical speeds of less than a few percent of the speed of light, despite the highly asymmetri…
The ACS Survey of Galactic Globular Clusters: M54 and Young Populations in the Sagittarius Dwarf Spheroidal Galaxy
Anderson, Jay; Dotter, Aaron; Majewski, Steven R. +11 more
As part of the ACS Survey of Galactic Globular Clusters, we present new Hubble Space Telescope photometry of the massive globular cluster M54 (NGC 6715) and the superposed core of the tidally disrupted Sagittarius (Sgr) dSph galaxy. Our deep (F606W ~ 26.5), high-precision photometry yields an unprecedentedly detailed color-magnitude diagram showin…
Coronal Pseudostreamers
Sheeley, N. R., Jr.; Wang, Y. -M.; Rich, N. B.
In a recent study of the 2006 solar eclipse, we noted that there are two kinds of coronal streamers: ``helmet streamers,'' which separate coronal holes of opposite magnetic polarity, and ``pseudostreamers,'' which overlie twin loop arcades and separate holes of the same polarity. It is well known that the heliospheric plasma and current sheets rep…
Emergence of Small-Scale Magnetic Loops in the Quiet-Sun Internetwork
Kubo, M.; Ichimoto, K.; Tsuneta, S. +11 more
We study the emergence of magnetic flux at very small spatial scales (less than 2") in the quiet-Sun internetwork. To this aim, a time series of spectropolarimetric maps was taken at disk center using the instrument SP/SOT on board Hinode. The LTE inversion of the full Stokes vector measured in the Fe I 6301 and 6302 Å lines allows us to retrieve …
A Wide-Field Survey of Two z ~ 0.5 Galaxy Clusters: Identifying the Physical Processes Responsible for the Observed Transformation of Spirals into S0s
Smith, Graham P.; Treu, Tommaso; Smail, Ian +3 more
We present new results from our comparative survey of two massive, intermediate-redshift galaxy clusters, Cl 0024+17 (z=0.39) and MS 0451-03 (z=0.54). Combining optical and UV imaging with spectroscopy of member galaxies, we identify and study several key classes of ``transition objects'' whose stellar populations or dynamical states indicate a re…
The Multiplicity of the Subgiant Branch of ω Centauri: Evidence for Prolonged Star Formation
Recio-Blanco, A.; Anderson, J.; Cool, A. M. +9 more
We combine spectroscopic and photometric data for subgiant stars of ω Cen to extract results that neither data set could have provided on its own. GIRAFFE@VLT spectra of 80 stars at R=6400 give metallicities for all of them and abundances of C, N, Ca, Ti, and Ba for a subset of them. The photometric data, which have unusually high accuracy, come f…