Search Publications
Using XMM-Newton to measure the spectrum of the Vela pulsar and its phase variation
De Luca, Andrea; Caraveo, Patrizia A.; Manzali, Armando
We report on our analysis of two XMM-Newton observations of the Vela pulsar performed in December 2000 (total exposure time: 96.5 ks). We succeeded in resolving the pulsar spectrum from the surrounding bright nebular emission taking advantage both of the accurate calibration of the EPIC point spread function and of the Chandra/HRC surface brightne…
Ultraviolet spectroscopy of Comet 9P/Tempel 1 with Alice/Rosetta during the Deep Impact encounter
Parker, Joel Wm.; Bertaux, Jean-Loup; Stern, S. Alan +5 more
We report on spectroscopic observations of periodic Comet 9P/Tempel 1 by the Alice ultraviolet spectrograph on the Rosetta spacecraft in conjunction with NASA's Deep Impact mission. Our objectives were to measure an increase in atomic and molecular emissions produced by the excavation of volatile sub-surface material. We unambiguously detected ato…
A near-ultraviolet view of the inner region of M 31 with the large binocular telescope
Pasian, F.; Fontana, A.; Grazian, A. +28 more
Aims:We present a 900 s, wide-field U image of the inner region of the Andromeda galaxy obtained during the commissioning of the blue channel of the Large Binocular Camera mounted on the prime focus of the Large Binocular Telescope.
Methods: Relative photometry and absolute astrometry of individual sources in the image was obtained along with …
Revised Periods for QS Geminorum and V367 Geminorum
Brown, Peter J.; Hintz, Eric G.
We have examined the field around the variable stars QS Geminorum and V367 Geminorum. For the δ Scuti-type variable QS Gem, we determined a revised period of 0.1346116 days, which is close to the originally published period from Hipparcos. For the eclipsing system V367 Gem, we found a period of 0.6992285 days, which is substantially different from…
Ultra-Low-Frequency Solar He II 30.4 nm Pulsations
Didkovsky, L.; Judge, D. L.; Gangopadhyay, P. +2 more
Solar EUV and X-ray measurements from the Charge, Element and Isotope Analysis System/Solar EUV Monitor (CELIAS/SEM) on board Solar and Heliospheric Observatory (SOHO) and the Geostationary Operational Environmental Satellites (GOES) have been studied for four time periods. Two ultra-low-frequency CELIAS/SEM He II 30.4 nm pulsations were observed …
Stellar population in bulge of spiral galaxies
Saglia, R. P.; Morelli, L.; Corsini, E. M. +6 more
We present a preliminary analysis of ASTRO-F data of a complete sample of ~150 EROs (R-K>5) down to K(Vega)<19, for which reliable photometric redshifts are available, in the range 0.8<z<2, selected over two fields (S7 and S2) of the MUNICS survey. The area covered is about 420 arcmin^2. We have imaged this area with AKARI telescope in…
X-ray emission of OH megamaser galaxies
Hambaryan, V. V.; Kandalyan, R. A.; Sabat, H. A.
The properties of OH megamaser galaxies in the x-ray region are discussed. Observational data from the XMM-Newton x-ray satellite are presented for three megamasers, IRAS 01418+1651, IRAS 11010+4107, and IRAS 13218+0552. Based on a sample of OH megamaser galaxies it is shown that the x-ray and OH emission are closely coupled. Megamaser emission al…
Evolution of coronal mass ejections in the early stage
Zhang, Hongqi; Lin, Jun; Li, Leping +2 more
This work reports the investigation of two coronal mass ejections (CME) observed in white light, Hα, EUV and X-ray by various instruments both in space and on ground on February 18, 2003 and January 19, 2005, respectively. The white light coronal images show that the first CME began with the rarefaction of a region above the solar limb and was fol…
Tracking UVCS/SOHO Responsivity with Observations of ζ Tau
Kohl, John L.; Raymond, John C.; Gardner, Larry D. +3 more
We have tracked the spectral responsivity of the ultraviolet channels of the UVCS (Ultraviolet Coronagraph Spectrometer) instrument on SOHO by repeated observations of a stable hot star. We demonstrate first that the ultraviolet spectral irradiance of the Be star ζ Tau (HD 37202) for the 100- to 125-nm wavelength range has been sufficiently consta…
Evolution of a Coronal Loop System
Wiegelmann, T.; Gontikakis, C.; Tziotziou, K. +3 more
The temporal variation of a loop system that appears to be changing rapidly is examined. The analyzed data were obtained on 15 May 1999, with the Transition Region and Coronal Explorer (TRACE) during an observing campaign and consist of observations in the Fe IX/Fe X 171 Å and Fe XII 195 Å passbands taken at a cadence of ∼10 min. The special inter…