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Procyon B: Outside the Iron Box
Provencal, J. L.; Bergeron, P.; Wesemael, F. +2 more
Procyon B is one of a select group of white dwarf stars in visual binaries that are used to put stringent constraints on the fundamental physics of stellar degeneracy. We present Space Telescope Imaging Spectrograph observations of this elusive white dwarf. Our spectra cover 1800-10000 Å and contain carbon Swan bands, Mg II, and numerous iron feat…
GRB 010222: A Burst within a Starburst
Menten, K. M.; Price, P. A.; Harrison, F. A. +17 more
We present millimeter- and submillimeter-wavelength observations and near-infrared K-band imaging toward the bright gamma-ray burst GRB 010222. Over seven different epochs, a constant source was detected with an average flux density of 3.74+/-0.53 mJy at 350 GHz and 1.05+/-0.22 mJy at 250 GHz, giving a spectral index α=3.78+/-0.25 (where F~να…
The Acceleration and Release of Near-relativistic Electrons by Coronal Mass Ejections
Simnett, G. M.; Roelof, E. C.; Haggerty, D. K.
We have examined transient coronal activity observed by the Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph Experiment (LASCO) around the release time of beams of near-relativistic electrons (~40-300 keV) observed by the Advanced Composition Explorer (ACE)/Electron, Proton, and Alpha Monitor (EPAM) at 1 AU. The …
A Galactic Wind at z=5.190
Dey, Arjun; Spinrad, Hyron; Stern, Daniel +4 more
We report the serendipitous detection in high-resolution optical spectroscopy of a strong, asymmetric Lyα emission line at z=5.190. The detection was made in a 2.25 hr exposure with the Echelle Spectrograph and Imager on the Keck II telescope through a spectroscopic slit of dimensions 1''×20''. The progenitor of the emission …
The Low End of the Initial Mass Function in Young Clusters. II. Evidence for Primordial Mass Segregation in NGC 330 in the Small Magellanic Cloud
Leitherer, Claus; Clampin, Mark; Nota, Antonella +2 more
As part of a larger program aimed at investigating the universality of the initial mass function (IMF) at low masses in a number of young clusters in the LMC and SMC, we present a new study of the low end of the stellar IMF of NGC 330, the richest young star cluster in the SMC, from deep broadband V and I images obtained with HST/WFPC2. We detect …
Characteristics of Coronal Inflows
Sheeley, N. R., Jr.; Wang, Y. -M.
This paper describes coronal inflows observed with the Large Angle Spectrometric Coronagraph (LASCO). The inflows are not seen above 5.5 Rsolar, which appears to be a ``point of no return'' for the Sun's plasmas and fields. Below this height, most inflows seem to indicate magnetic flux that is returning to the Sun after its reconnection…
Evidence for Tidal Stripping of Dark Matter Halos in Massive Cluster Lenses
Smail, Ian; Kneib, Jean-Paul; Natarajan, Priyamvada
In this Letter, we present the results of our study of galaxy-galaxy lensing in massive cluster lenses spanning z=0.17-0.58, utilizing high-quality archival Hubble Space Telescope data. Local anisotropies in the shear maps are assumed to arise from dark matter substructure within these clusters. Associating the substructure with bright early-type …
K-Band Red Clump Distance to the Large Magellanic Cloud
Minniti, Dante; Rejkuba, Marina; Alves, David R. +1 more
The Hipparcos I-band calibration of horizontal-branch red clump giants as standard candles has lead to controversial results for the distance to the Large Magellanic Cloud (LMC). In an attempt to properly ascertain the corrections for interstellar extinction and clump age and metallicity, we analyze new multiwavelength luminosity functions of the …
Nuclear Cusps and Cores in Early-Type Galaxies as Relics of Binary Black Hole Mergers
Ravindranath, Swara; Filippenko, Alexei V.; Ho, Luis C.
We present an analysis of the central cusp slopes and core parameters of early-type galaxies using a large database of surface brightness profiles obtained from Hubble Space Telescope observations. We examine the relation between the central cusp slopes, core parameters, and black hole masses in early-type galaxies, in light of two models that att…
Observations of T Tauri Stars using Hubble Space Telescope GHRS. I. Far-Ultraviolet Emission Lines
Valenti, Jeff A.; Walter, Frederick M.; Ardila, David R. +2 more
We have analyzed Goddard High Resolution Spectrograph data of eight classical T Tauri stars (CTTSs) and one weak-lined T Tauri star (WTTS). The GHRS data consist of spectral ranges 40 Å wide centered on 1345, 1400, 1497, 1550, and 1900 Å. These UV spectra show strong Si IV and C IV emission and large quantities of sharp (~40 km s-1) H