Search Publications
Missions
Journals
Publication Years
Metallicities of the SPB stars from the IUE ultraviolet spectra
Niemczura, E.
We derived the stellar parameters (angular diameters, effective temperatures, metallicities) and interstellar reddenings for 20 SPB and 34 reference stars observed during the IUE satellite mission. The parameters were derived by means of an algorithmic procedure of fitting theoretical flux distributions to the low-resolution IUE spectra and optica…
Acceleration and Enrichment of 3He in Impulsive Solar Flares by Electron Firehose Waves
Benz, A. O.; Kallenbach, R.; Paesold, G.
A new mechanism for acceleration and enrichment of 3He during impulsive solar flares is presented. Low-frequency electromagnetic plasma waves excited by the electron firehose instability (EFI) can account for the acceleration of ions up to 1 MeV amu-1 energies as a single-stage process. The EFI arises as a direct consequence …
Tracing a Z-track in the M 31 X-ray binary RX J0042.6+4115
Kolb, U.; Osborne, J. P.; Barnard, R.
Four XMM-Newton observations of the core of M 31, spaced at 6 month intervals, show that the brightest point X-ray source, RX J0042.6+4115, has a 0.4-10 keV luminosity of ~ 5x 1038 erg s-1, and exhibits significant variability in intensity and X-ray spectrum over a time scale of ~ 100 s including hard flares; such behaviour i…
The detection of diffuse emission in HCG 16 with XMM-Newton
Bourdin, H.; Ponman, T. J.; Sauvageot, J. -L. +1 more
We report results obtained from analysis of the XMM-Newton observation of the compact group of galaxies HCG 16. It is a peculiar system composed of 7 spirals, 6 of which are active, and its nature as a bound system has been much debated. The EPIC camera observations give new insights into the X-ray parameters describing the physical status of the …
Deep XMM-Newton observation of a northern LMC field I. Selected X-ray sources
Pietsch, W.; Haberl, F.; Dennerl, K.
First results from a deep XMM-Newton observation of a field in the Large Magellanic Cloud (LMC) near the northern rim of the supergiant shell LMC 4 are presented. Spectral and temporal analyses of a sample of selected X-ray sources yielded two new candidates for supernova remnants, a supersoft X-ray source and a likely high mass X-ray binary (HMXB…
The Dynamical Morphologies of Flares Associated with the Two Types of Solar Coronal Mass Ejections
Golub, Leon; Zhang, Mei
In this paper we study the high-cadence TRACE observations of a sample of 28 X- and M-class flares, with particular focus on the relation between flare morphology and the two types (fast and slow) of solar coronal mass ejections (CMEs). Among the 28 flares studied, 10 are associated with fast CMEs, 10 are associated with slow CMEs, and 8 are loose…
The mineralogy, geometry and mass-loss history of IRAS 16342-3814
Waters, L. B. F. M.; Dominik, C.; de Koter, A. +5 more
We present the 2-200 mu m Infrared Space Observatory (ISO) spectrum and 3.8-20 mu m ISAAC and TIMMI2 images of the extreme OH/IR star IRAS 16342-3814. Amorphous silicate absorption features are seen at 10 and 20 mu m, together with crystalline silicate absorption features up to almost 45 mu m. No other OH/IR star is known to have crystalline silic…
Statistical Characteristics of CMEs and Flares Associated with Solar Type II Radio Bursts
Moon, Y. -J.; Shanmugaraju, A.; Dryer, M. +1 more
We have made a comprehensive statistical study of the characteristics of 290 SOHO/LASCO CMEs and their associated GOES-8 X-ray flares (> C1 class) during the period January 1997-December 2000 of solar cycle 23's rise to maximum. These events were classified into mainly three groups (Group noII - not associated with type IIs, Group II - associat…
Plasma sheet structure during strongly northward IMF
Petrukovich, A. A.; Balogh, A.; Glassmeier, K. -H. +5 more
On 14 September 2001, under stongly northward IMF conditions Cluster registered several fast magnetic field polarity changes which are usually attributed to thin (near-equatorial) current sheet crossings. However, the IMF was northward for the previous 24 hours, the plasma sheet was expanded vertically, filled with cold, dense plasmas with high lo…
An XMM-Newton Observation of Nova LMC 1995: A Bright Supersoft X-Ray Source
Orio, Marina; Greiner, Jochen; Still, Martin +1 more
Nova LMC 1995, previously detected during 1995-1998 with ROSAT, was observed again as a luminous supersoft X-ray source with XMM-Newton in 2000 December. This nova offers the possibility to observe the spectrum of a hot white dwarf, burning hydrogen in a shell and not obscured by a wind or nebular emission as in other supersoft X-ray sources. Notw…