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The Main-Sequence Luminosity Function of Palomar 5 from THE HUBBLE SPACE TELESCOPE
Smith, Graeme H.; Grillmair, Carl J.
A low mass, large core radius, low central concentration, and strong tidal tails suggest that the globular cluster Palomar 5 has lost a large fraction of its initial mass over time. If the dynamical evolution of Pal 5 has been dominated by the effects of mass loss, then theoretical arguments suggest that the luminosity function should be deficient…
Coronal Inflows and the Sun's Nonaxisymmetric Open Flux
Sheeley, N. R., Jr.; Wang, Y. -M.; Knudson, T. N.
Wang et al. recently described white-light coronagraph observations of faint coronal features moving inward toward the Sun at heliocentric distances of 2-6 Rsolar. In a study of these inflows during 1996-2000, we have found that they occur along bends of the coronal streamer belt and are especially common when the magnetic field has a f…
Coordinated 1996 HST and IRTF Imaging of Neptune and Triton. II. Implications of Disk-Integrated Photometry
Baines, K. H.; Sromovsky, L. A.; Fry, P. M. +1 more
Near-IR groundbased observations coordinated with Wide Field Planetary Camera 2 (WFPC2) HST observations (Sromovsky et al.Icarus149, 416-434, 459-488) provide new insights into the variations of Neptune and Triton over a variety of time scales. From 1996 WFPC2 imaging we find that a broad circumpolar nonaxisymmetric dark band dominates Neptune's l…
Double Loop Configuration of a Flaring Region from Microwave, Extreme-Ultraviolet, and X-Ray Imaging Data
Kundu, M. R.; White, S. M.; Grechnev, V. V. +1 more
We use extensive multiwavelength data to study a flare belonging to the interacting-loop class of events identified by Hanaoka. The class of flares is identified morphologically from the presence of two well-separated radio sources in 17 GHz images (in this event, 160" apart), with only one source showing soft X-ray emission. This event shows many…
Hubble Space Telescope Images of the Ultraluminous Supernova Remnant Complex in NGC 6946
Blair, William P.; Fesen, Robert A.; Schlegel, Eric M.
We present Hubble Space Telescope (HST) narrow-passband Hα and [S II] images and broadband continuum images of the region around an extremely luminous optical and X-ray supernova remnant complex in the spiral galaxy NGC 6946. These images, obtained with the PC1 CCD of the Wide Field Planetary Camera 2, show a circular, limb-brightened shell of dia…
Kinematics of Molecular Hydrogen Emission from Pre-Planetary Nebulae: RAFGL 2688 and RAFGL 618
Kastner, Joel H.; Weintraub, David A.; Gatley, Ian +1 more
We present high spectral resolution maps of near-infrared molecular hydrogen emission from the bipolar pre-planetary nebulae RAFGL 2688 and RAFGL 618, obtained with the NOAO Phoenix spectrometer. The measured velocity gradients along the polar axes of both nebulae indicate that the highest velocity gas lies closest to the central stars. These resu…
Charge-equilibration of Fe ions accelerated in a hot plasma
Torsti, J.; Kocharov, L.; Kovaltsov, G. A. +2 more
We examine the energy-dependent rates of charge-changing processes of energetic Fe ions in the hot plasma of the solar corona. For ionization of the Fe-ion projectile in collisions with ambient protons, three different methods of estimating the corresponding ionization cross sections are presented and compared. Proton-impact ionization is found to…
A Massive Disk Galaxy at z=1.34
van Dokkum, Pieter G.; Stanford, S. A.
We report on the discovery of a rapidly rotating disk in a K-selected galaxy at z=1.34. Spatially resolved kinematics are determined from deep, moderate-resolution Keck spectroscopy covering the redshifted [O II] 3727 Å line. A conservative estimate of the maximum rotation velocity Vmax=290+/-20 km s-1, placing the galaxy amo…
Simultaneous Observations of Solar Energetic Particle Events by imp 8 and the Ulysses Cospin High Energy Telescope at High Solar Latitudes
McKibben, R. B.; Zhang, M.; Lopate, C.
With Ulysses approaching the south solar polar latitudes during a period of high solar activity, it is for the first time possible to study the distribution of solar energetic particles (SEPs) in solar latitude as well as in radius and longitude. From July 1997 to August 2000, Ulysses moved from near the solar equator at ∼5 AU to ∼67° S latitude a…
Discovery of an Extremely Red Galaxy at z=0.65 with Dusty Star Formation and Nuclear Activity
Mobasher, B.; Afonso, J.; Chan, B. +1 more
In the course of the follow-up multiwavelength study of a deep radio survey, we have discovered that the millijansky radio source PDF J011423 is a low-redshift (z=0.65) extremely red galaxy (ERG) with K=15.3, R-K=5.8, and J-K=3.1. Optical, infrared, and radio photometry, together with optical and near-infrared spectroscopy, reveal a heavily obscur…