Search Publications
Comparison of Interplanetary CME Charge State Composition with CME-associated Flare Magnitude
Reinard, A.
This paper describes a study of the charge state composition of interplanetary coronal mass ejection (ICME) ejecta in the heliosphere within the context of remote-sensing CME observations at the Sun. First, CME-ICME pairs are examined to determine if a given CME is associated with a flare event. Then, for each ICME, the charge states, O+7
Halos of Spiral Galaxies. II. Halo Metallicity-Luminosity Relation
Ferguson, H. C.; Rich, R. M.; Mouhcine, M. +2 more
Using the Hubble Space Telescope, we have resolved individual red giant branch stars in the halos of eight nearby spiral galaxies. The fields lie at projected distances between 2 and 13 kpc along the galaxies' minor axes. The data set allows a first look at the systematic trends in halo stellar populations. We have found that bright galaxies tend …
The Magnetic Structure of Filament Barbs
Moon, Yong-Jae; Chae, Jongchul; Park, Young-Deuk
There is a controversy about how features protruding laterally from filaments, called barbs, are magnetically structured. On 2004 August 3, we observed a filament that had well-developed barbs. The observations were performed using the 10 inch refractor of the Big Bear Solar Observatory. A fast camera was employed to capture images at five differe…
Hubble Space Telescope ACS Weak-Lensing Analysis of the Galaxy Cluster RDCS 1252.9-2927 at z = 1.24
Ford, H. C.; Demarco, R.; Rosati, P. +12 more
We present a weak-lensing analysis of one of the most distant massive galaxy clusters known, RDCS 1252.9-2927, at z=1.24, using deep images from the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). By taking advantage of the depth and angular resolution of the ACS images, we detect for the first time at z>1 a clear w…
Halos of Spiral Galaxies. III. Metallicity Distributions
Ferguson, H. C.; Rich, R. M.; Mouhcine, M. +2 more
We report results of a campaign to image the stellar populations in the halos of highly inclined spiral galaxies, with the fields roughly 10 kpc (projected) from the nuclei. We use the F814W (I) and F606W (V) filters in the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. We unambiguously resolve the stellar halos 1 to 2 mag fain…
Space Telescope Imaging Spectrograph Ultraviolet/Optical Spectroscopy of ``Warm'' Ultraluminous Infrared Galaxies
Veilleux, S.; Sanders, D. B.; Surace, J. A. +2 more
We present high spatial resolution ultraviolet and optical spectroscopy, obtained using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, of nuclear structures within four ``warm'' ultraluminous infrared galaxies (ULIRGs). We find an active galactic nucleus (AGN) in at least three and probably all four in our sample, ho…
The Transformation of Cluster Galaxies at Intermediate Redshift
Ford, H. C.; Demarco, R.; Infante, L. +40 more
We combine imaging data from the Advanced Camera for Surveys (ACS) with VLT/FORS optical spectroscopy to study the properties of star-forming galaxies in the z=0.837 cluster Cl 0152-1357. We have morphological information for 24 star-forming cluster galaxies, which range in morphology from late-type and irregular to compact early-type galaxies. We…
Extragalactic Source Counts in the 20-50 keV Energy Band from the Deep Observation of the Coma Region by INTEGRAL IBIS
Sunyaev, R.; Krivonos, R.; Churazov, E. +3 more
We present the analysis of serendipitous sources in a deep, 500 ks, hard X-ray observation of the Coma Cluster region with the IBIS instrument on board INTEGRAL. In addition to the Coma Cluster, the final 20-50 keV image contains 12 serendipitous sources with statistical significance >4 σ. We use these data (after correcting for expected number…
The Connection between the Narrow-Line Region and the UV Absorbers in Seyfert Galaxies
Kraemer, S. B.; Crenshaw, D. M.
We present evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow- (emission-) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. Hubble Space Telescope observations show that nearly all Seyfert galaxies have bright, central knots of [O III] emission in…
Spatially Resolved Spectroscopy and Coronagraphic Imaging of the TW Hydrae Circumstellar Disk
Weinberger, Alycia J.; Roberge, Aki; Malumuth, Eliot M.
We present the first spatially resolved spectrum of scattered light from the TW Hydrae protoplanetary disk. This nearly face-on disk is optically thick, surrounding a classical T Tauri star in the nearby 10 Myr old TW Hya association. The spectrum was taken with the Hubble Space Telescope (HST) STIS CCD, providing resolution R~360 over the wavelen…