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An 850 Micron SCUBA Survey of the Hubble Deep Field-North GOODS Region
Wang, W. -H.; Barger, A. J.; Cowie, L. L.
The Hubble Deep Field-North (HDF-N) is one of the best-studied extragalactic fields, and ultradeep optical, radio, X-ray, and mid-infrared wide-field images are available for this area. Here we present an 850 µm survey around the HDF-N, covering most of the area imaged by the Advanced Camera for Surveys as a part of the Great Observatories O…
X-ray source populations in the Galactic plane
Warwick, R. S.; Watson, M. G.; Helfand, D. J. +1 more
We present the first results from the XMM-Newton Galactic Plane Survey (XGPS). In the first phase of the programme, 22 pointings were used to cover a region of approximately 3 deg2 between 19° and 22° in Galactic longitude and +/-0.6° in latitude. In total we have resolved over 400 point X-ray sources, at >= 5σ significance, down to …
Relativistic spectral features from X-ray-illuminated spots and the measure of the black hole mass in active galactic nuclei
Bianchi, S.; Guainazzi, M.; Matt, G. +2 more
Narrow spectral features in the 5-6 keV range were recently discovered in the X-ray spectra of a few active galactic nuclei. We discuss the possibility that these features are due to localized spots which occur on the surface of an accretion disc following its illumination by flares. We present detailed line profiles as a function of orbital phase…
Metals and Dust in Intermediate-Redshift Damped Lyα Galaxies
York, Donald G.; Kulkarni, Varsha P.; Lauroesch, James T. +3 more
We report on spectroscopic observations with the Multiple Mirror Telescope for 11 damped Lyα absorbers (DLAs) or strong DLA candidates at 0.1<z<1.5, including several absorbers discovered in the Sloan Digital Sky Survey. In particular, we have measured absorption lines of Zn II, Cr II, Ni II, Fe II, Mn II, Ti II, Ca II, and Si II. These meas…
The Detailed Fundamental Plane of Two High-Redshift Clusters: MS 2053-04 at z=0.58 and MS 1054-03 at z=0.83
van Dokkum, Pieter G.; Franx, Marijn; Kelson, Daniel D. +2 more
We study the fundamental plane relation in high-redshift clusters using a sample of 26 galaxies in MS 2053-04 (z=0.583) and 22 galaxies in MS 1054-03 (z=0.83). The zero point and scatter are compared to results for lower redshift clusters in order to trace evolutionary effects. Furthermore, our large sample enables us to investigate correlations b…
Probing the Intergalactic Medium-Galaxy Connection toward PKS 0405-123. I. Ultraviolet Spectroscopy and Metal-Line Systems
Weiner, Benjamin J.; Chen, Hsiao-Wen; Howk, J. Christopher +2 more
We present results from an analysis of FUSE spectroscopy of the zem=0.57 quasar PKS 0405-123. We focus on the intervening metal-line systems identified along the sight line and investigate their ionization mechanism, ionization state, and chemical abundances. Including Hubble Space Telescope STIS spectroscopy, we survey the entire sight…
A Possible New Population of Sources with Extreme X-Ray/Optical Ratios
Koekemoer, Anton M.; Alexander, D. M.; Bauer, F. E. +13 more
We describe a possible new class of X-ray sources that have robust detections in ultradeep Chandra data yet have no detections at all in our deep multiband Great Observatories Origins Deep Survey Hubble Space Telescope Advanced Camera for Surveys (ACS) images, which represent the highest quality optical imaging obtained to date on these fields. Th…
ISO observations of the Galactic center interstellar medium. Neutral gas and dust
Rodríguez-Fernández, N. J.; Martín-Pintado, J.; Fuente, A. +1 more
The 500 central pc of the Galaxy (hereafter GC) exhibit a widespread gas component with a kinetic temperature of 100-200 K. The bulk of this gas is not associated to the well-known thermal radio continuum or far infrared sources like Sgr A or Sgr B. How this gas is heated has been a longstanding problem. With the aim of studying the thermal balanc…
Coronal Mass Ejection of 15 May 2001: I. Evolution of Morphological Features of the Eruption
Maričić, D.; Vršnak, B.; Stanger, A. L. +1 more
We study the initiation and development of the limb coronal mass ejection (CME) of 15 May 2001, utilizing observations from Mauna Loa Solar Observatory (MLSO), the Solar and Heliospheric Observatory (SOHO), and Yohkoh. The pre-eruption images in various spectral channels show a quiescent prominence imbedded in the coronal void, being overlaid by t…
Far-infrared and submillimetre observations of the Crab nebula
Tuffs, R. J.; Popescu, C. C.; Green, D. A.
We present far-infrared (FIR) and submillimetre images of the Crab nebula, taken with the ISOPHOT instrument onboard the Infrared Space Observatory (ISO) and with the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. The ISOPHOT observations were made in the bands centred at 60, 100 and 170 µm, with FWHM…