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Production, ionization and redistribution of O 2 in Saturn's ring atmosphere
Luhmann, J. G.; Tokar, R. L.; Johnson, R. E. +10 more
Molecular oxygen produced by the decomposition of icy surfaces is ubiquitous in Saturn's magnetosphere. A model is described for the toroidal O 2 atmosphere indicated by the detection of O2+ and O + over the main rings. The O 2 ring atmosphere is produced primarily by UV photon-induced decomposition of ice on the s…
Black Hole Mass of the Ultraluminous X-Ray Source M82 X-1
Dewangan, Gulab C.; Griffiths, Richard E.; Titarchuk, Lev
We report the first clear evidence for the simultaneous presence of a low-frequency break and a QPO in the fluctuation power spectrum of a well-known ultraluminous X-ray source (ULX) in M82 using long XMM-Newton observations. The break occurs at a frequency of 34.2+6-3 mHz. The QPO has a centroid at νQPO=114.3+/-1.…
Infrared photometry and evolution of mass-losing AGB stars. I. Carbon stars revisited
Ciprini, S.; Guandalini, R.; Busso, M. +2 more
As part of a reanalysis of galactic Asymptotic Giant Branch (AGB) stars at infrared (IR) wavelengths, we discuss a sample (357) of carbon stars for which mass loss rates, near-IR photometry and distance estimates exist. For 252 sources we collected mid-IR fluxes from the MSX (6C) and the ISO-SWS catalogues. Most stars have spectral energy distribu…
uvby-β photometry of high-velocity and metal-poor stars. XI. Ages of halo and old disk stars
Moitinho, A.; Schuster, W. J.; Parrao, L. +2 more
New uvby-β data are provided for 442 high-velocity and metal-poor stars; 90 of these stars have been observed previously by us, and 352 are new. When combined with our previous two photometric catalogues, the data base is now made up of 1533 high-velocity and metal-poor stars, all with uvby-β photometry and complete kinematic data, such as proper …
Low-Mass X-Ray Binaries in Six Elliptical Galaxies: Connection to Globular Clusters
Lee, Myung Gyoon; Fabbiano, Giuseppina; Geisler, Doug +4 more
We present a systematic study of the low-mass X-ray binary (LMXB) populations of six elliptical galaxies, aimed at investigating the detected LMXB-globular cluster (GC) connection. We utilize Chandra archival data to identify X-ray point sources and HST archival data supplemented by ground observations to identify 6173 GCs. After screening and cro…
Cassini observations of Saturn's inner plasmasphere: Saturn orbit insertion results
Coates, A. J.; Johnson, R. E.; Thomsen, M. +13 more
We present new and definitive results of Cassini plasma spectrometer (CAPS) data acquired during passage through Saturn's inner plasmasphere by the Cassini spacecraft during the approach phase of the Saturn orbit insertion period. This analysis extends the original analysis of Sittler et al. [2005. Preliminary results on Saturn's inner plasmaspher…
Enhanced Abundances in Three Large-Diameter Mixed-Morphology Supernova Remnants
Slane, P. O.; Lazendic, J. S.
We present an X-ray study of three mixed-morphology (MM) supernova remnants (SNRs)-HB 21, CTB 1, and HB 3-using archival ASCA and ROSAT data. These data are complemented by archival Chandra X-Ray Observatory data for CTB 1 and XMM-Newton X-Ray Observatory data for HB 3. The spectra from HB 21 and HB 3 are well described with a single-temperature t…
Constraining the population of 6 ⪉ {z} ⪉ 10 star-forming galaxies with deep near-IR images of lensing clusters
Kneib, J. -P.; Schaerer, D.; Pelló, R. +2 more
We present the first results of our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z∼6-10, using lensing magnification to improve the search efficiency and subsequent spectroscopic studies. Deep near-IR photometry of two lensing clusters (A1835 and AC114) was obtained with ISAAC/VLT. These images, c…
Rapid evolution of the most luminous galaxies during the first 900million years
Illingworth, Garth D.; Bouwens, Rychard J.
The first 900 million years (Myr) to redshift z ~ 6 (the first seven per cent of the age of the Universe) remains largely unexplored for the formation of galaxies. Large samples of galaxies have been found at z ~ 6 (refs 1-4) but detections at earlier times are uncertain and unreliable. It is not at all clear how galaxies built up from the first s…
Current Sheet Evolution in the Aftermath of a CME Event
Raymond, J. C.; Bemporad, A.; Poletto, G. +4 more
We report on SOHO UVCS observations of the coronal restructuring following a coronal mass ejection (CME) on 2002 November 26, at the time of a SOHO-Ulysses quadrature campaign. Starting about 1.5 hr after a CME in the northwest quadrant, UVCS began taking spectra at 1.7 Rsolar, covering emission from both cool and hot plasma. Observatio…