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First XMM-Newton observations of strongly magnetic cataclysmic variables - I. Spectral studies of DP Leo and WW Hor
Cropper, Mark; Ramsay, Gavin; Córdova, France +4 more
We present an analysis of the X-ray spectra of two strongly magnetic cataclysmic variables, DP Leo and WW Hor, made using XMM-Newton. Both systems were in intermediate levels of accretion. Hard optically thin X-ray emission from the shocked accreting gas was detected from both systems, while a soft blackbody X-ray component from the heated surface…
XMM-Newton EPIC and RGS observations of LMC X-3
Page, M. J.; de Vries, C. P.; Soria, R. +3 more
We report the results of preliminary analysis of the {XMM-Newton} EPIC and RGS observations of the candidate black-hole binary LMC X-3 between February and June 2000. The observations covered both the soft and the hard X-ray spectral states. The hard-state spectra were dominated by a power-law component with a photon index Gamma ~1.9. The soft-sta…
Evidence for a Very Young Age of F Stars with Extrasolar Planets
Schultz, A. B.; Suchkov, A. A.
We assess the age of nine planet-bearing (PB) F stars by comparing their metallicity, Hp variability, brightness anomaly, and location in the color-magnitude diagram with the same parameters for the Hyades and field F stars. Combined evidence from these parameters suggests that the age of our PB F stars is not very much different from the age of t…
Detection of H2 Emission from Mira B in Ultraviolet Spectra from the Hubble Space Telescope
Wood, Brian E.; Karovska, Margarita; Hack, Warren
We present ultraviolet spectra of Mira's companion star from the Space Telescope Imaging Spectrograph (STIS) instrument on board the Hubble Space Telescope (HST). The companion is generally assumed to be a white dwarf surrounded by an accretion disk fed by Mira's wind, which dominates the UV emission from the system. The STIS UV spectrum is domina…
The Physics of the Solar Lower Transition Region
Doschek, G. A.; Mariska, J. T.
We discuss quiet-Sun intensities of spectral lines of O IV λ1401.16 and Si IV λ1402.77, their ratio, and their relation to expected properties of the lower solar transition region. The data consist of simultaneous measurements of the two line intensities for 16,988 pixels with spatial dimensions of 1" square obtained by the Solar Ultraviolet Measu…
Young Clusters in the Magellanic Clouds. II.
Da Costa, G. S.; Bessell, M. S.; Keller, Stefan C.
We present the results of a quantitative study of the degree of extension to the boundary of the classical convective core within intermediate-mass stars. The basis of our empirical study is the stellar population of four young populous clusters in the Magellanic Clouds that has recently been detailed by Keller, Bessell, & Da Costa. The sample…
Global Asymmetry of the Sun Observed in the Extreme Ultraviolet Radiation
Zhukov, A. N.; Hochedez, J. F.; Veselovsky, I. S. +4 more
We report on observations of the solar luminosity variations in the Fe xii line (195 Å) over the period 1996-1999, which corresponds to the minimum and rising phase of the current 23rd solar cycle. The relatively or rather high temporal cadence and spatial resolution of the Extreme-ultraviolet Imaging Telescope (EIT) on board the Solar and Heliosp…
Gas cooling within the diffuse ISM of late-type galaxies
Boselli, A.; Völk, H. J.; Lequeux, J. +2 more
We combine observations of spiral galaxies in the [CII] line at 158 mu m, made with the Long Wavelength Spectrometer aboard ISO, with previous data from the Kuiper Airborne Observatory to study the origin of this line, which is the main coolant of the interstellar medium at relatively low temperatures. We also use HI and CO(1-0) observations of th…
Detection of magnetic dipole lines of Fexii in the ultraviolet spectrum of the dwarf star ɛ Eri
McMurry, A. D.; Jordan, C.; Sim, S. A. +1 more
We report observations of the dwarf star ɛ Eri (K2V) made with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope. The high sensitivity of the STIS instrument has allowed us to detect the magnetic dipole transitions of Fexii at 1242.00 and 1349.38Å for the first time in a star other than the Sun. The width of the stronge…
A Critical Examination of Hypernova Remnant Candidates in M101. I. MF 83
Grebel, Eva K.; Lai, Shih-Ping; Ciardullo, Robin +2 more
The supernova remnant (SNR) candidate MF 83 in M101 is coincident with a very luminous X-ray source. Based on the high X-ray luminosity, it has been suggested that MF 83 is a ``hypernova remnant'' requiring an explosion energy about 2 orders of magnitude higher than normal supernovae. We have analyzed high-quality ground-based and Hubble Space Tel…