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Deep Near-Infrared Luminosity Function of a Cluster of Galaxies at Z=0.3
Andreon, S.
The deep near-infrared luminosity function of AC 118, a cluster of galaxies at z=0.3, is presented. AC 118 is a bimodal cluster, as evidenced both by our near-infrared images of lensed galaxies, by public X-ray ROSAT images, and by the spatial distribution of bright galaxies. Taking advantage of the extension and depth of our data, which sample an…
Variable Interstellar Absorption toward the Halo Star HD 219188: Implications for Small-Scale Interstellar Structure
Fitzpatrick, Edward L.; Welty, Daniel E.
Within the last 10 yr, strong, narrow Na I absorption has appeared at vsolar~-38 km s-1 toward the halo star HD 219188; that absorption has continued to strengthen, by a factor of 2-3, over the past 3 yr. The line of sight appears to be moving into/through a relatively cold, quiescent intermediate-velocity (IV) cloud, because…
The Large-Scale Ionized Outflow of CH Cygni
Livio, Mario; Corradi, Romano L. M.; Gonçalves, Denise R. +3 more
Hubble Space Telescope (HST) and ground-based [O II] and [N II] images obtained in the period 1996-1999 reveal a complex, ionized optical nebula around the symbiotic binary CH Cyg extending out to 18" or 5000 AU from the central stars. The observed velocity range of the nebula, derived from long-slit echelle spectra, is 130 km s-1. In s…
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…
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…
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…
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…
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…
QSO 2359-1241: A Bright, Highly Polarized, Radio-moderate, Reddened, Low-Ionization Broad Absorption Line Quasar
Gregg, Michael D.; Becker, R. H.; Arav, Nahum +5 more
We report the discovery of a bright quasar (E=15.8, z=0.868) associated with the flat-spectrum radio source NVSS J235953-124148. This quasar, which we designate QSO 2359-1241, possesses a rare combination of extreme properties that make it of special interest. These properties include intrinsic high-velocity outflow seen in absorption for both hig…
Topology of the Galaxy Distribution in the Hubble Deep Fields
Park, Changbom; Gott, J. Richard, III; Choi, Y. J.
We have studied topology of the distribution of the high-redshift galaxies identified in the Hubble Deep Field (HDF) North and South. The two-dimensional genus is measured from the projected distributions of the HDF galaxies at angular scales from 3.8" to 6.1". We have also divided the samples into three redshift slices with roughly equal numbers …