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The opacity of spiral galaxy disks. V. Dust opacity, HI distributions and sub-mm emission
Allen, Ronald J.; Holwerda, B. W.; van der Kruit, P. C. +1 more
The opacity of spiral galaxy disks, from counts of distant galaxies, is compared to HI column densities. The opacity measurements are calibrated using the "Synthetic Field Method" from González et al. (1998, ApJ, 506, 152), Holwerda et al. (2005a, AJ, 129, 1381). When compared for individual disks, the HI column density and dust opacity do not see…
Magnetosheath Interaction with the High Latitude Magnetopause
Khotyaintsev, Y.; Amata, E.; Fritz, T. A. +23 more
We present both statistical and case studies of magnetosheath interaction with the high-latitude magnetopause on the basis of Interball-1 and other ISTP spacecraft data. We discuss those data along with recently published results on the topology of cusp-magnetosheath transition and the roles of nonlinear disturbances in mass and energy transfer ac…
Outflows in the Orion Nebula: HH 540 from the Beehive Proplyd
Smith, Nathan; Bally, John; Walawender, Josh +1 more
We present Hubble Space Telescope Advanced Camera for Surveys images of the giant proplyd 181-826 in the southern Orion Nebula. This object exhibits a variety of known proplyd properties-an optically visible central star, a silhouette disk, a bright proplyd ionization front, and a bipolar microjet emerging along the disk axis that powers a larger …
The Halo, Hot Spots, and Jet/Cloud Interaction of PKS 2153-69
Young, A. J.; Heinz, S.; Wilson, A. S. +1 more
We report Chandra X-Ray Observatory and 1.4 GHz Australian Long Baseline Array (LBA) observations of the radio galaxy PKS 2153-69 and its environment. The Chandra image reveals a roughly spherical halo of hot gas extending out to 30 kpc around PKS 2153-69. Two depressions in the surface brightness of the X-ray halo correspond to the large-scale ra…
An XMM-Newton observation of the multiple system HD 167971 (O5-8V + O5-8V + (O8I)) and the young open cluster NGC 6604
Blomme, R.; Rauw, G.; De Becker, M. +3 more
We discuss the results of two XMM-Newton observations of the open cluster NGC 6604 obtained in April and September 2002. We concentrate mainly on the multiple system HD 167971 (O5-8V + O5-8V + (O8I)). The soft part of the EPIC spectrum of this system is thermal with typical temperatures of about 2 × 106 to 9 × 106 K. The natu…
Statistics of high-altitude and high-latitude O+ ion outflows observed by Cluster/CIS
Lundin, R.; Yamauchi, M.; Nilsson, H. +8 more
The persistent outflows of O+ ions observed by the Cluster CIS/CODIF instrument were studied statistically in the high-altitude (from 3 up to 11 RE) and high-latitude (from 70 to ~90 deg invariant latitude, ILAT) polar region. The principal results are: (1) Outflowing O+ ions with more than 1keV are observed above …
The very low-mass population of the Corona Australis and Chamaeleon II star forming regions
Eislöffel, J.; López Martí, B.; Mundt, R.
We present the results of a deep optical survey in the Corona Australis and Chamaeleon II star forming regions. Our optical photometry is combined with available near- and mid-infrared photometry to identify very low-mass candidate members in these dark clouds. In our Chamaeleon II field, only one object exhibits clear Hα emission, but the discrep…
Far Ultraviolet Spectroscopic Explorer Observations of the Symbiotic Star AG Draconis
Young, P. R.; Dupree, A. K.; Espey, B. R. +2 more
Spectra of the bright symbiotic star AG Draconis (BD +67°922) in the wavelength range 905-1187 Å obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) are presented. The spectra show a number of narrow, nebular emission lines, together with a uniform continuum from the hot component of the system, and numerous interstellar absorption lin…
A possible bright blue supernova in the afterglow of GRB 020305
Nugent, P.; Fynbo, J. P. U.; Gorosabel, J. +8 more
We report on ground-based and HST(+STIS) imaging of the afterglow and host galaxy of the Gamma-Ray Burst (GRB) of March 5, 2002. The GRB occurred in a R=25.17 ± 0.14 galaxy, which apparently is part of an interacting system. The lightcurve of the optical afterglow shows a rebrightening, or at least a plateau, 12 16 days after the gamma-ray event. …
RR Lyrae stars: kinematics, orbits and z-distribution
de Boer, K. S.; Maintz, G.
RR Lyrae stars in the Milky Way are good tracers to study the kinematic behaviour and spatial distribution of older stellar populations. A recently established well documented sample of 217 RR Lyr stars with V<12.5 mag, for which accurate distances and radial velocities as well as proper motions from the Hipparcos and Tycho-2 catalogues are ava…