Search Publications
Injection of energetic protons during solar eruption on 1999 May 9: Effect of flare and coronal mass ejection
Torsti, J.; Innes, D. E.; Kocharov, L. +2 more
A solar energetic particle (SEP) event was observed on 1999 May 9 by the Energetic and Relativistic Nuclei and Electron instrument (ERNE) onboard the Solar and Heliospheric Observatory (SOHO) spacecraft in association with a coronal mass ejection (CME) and X-ray flare at the western limb. Near flare onset the active region coronal loop structure w…
Spectral imaging maps of AR Lacertae . I. Results from IUE observations in 1994 October
Pagano, I.; Linsky, J. L.; Rodonò, M. +4 more
In October 1994 the RS CVn eclipsing binary
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…
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…
A relation between dynamics of coronal mass ejections and production of solar energetic particles
St. Cyr, O. C.; Torsti, J.; Kocharov, L. +1 more
During January 1997-June 1998, the Large Angle Spectroscopic Coronagraph (LASCO) aboard the Solar and Heliospheric Observatory spacecraft (SOHO) registered 670 coronal mass ejections (CMEs). We compare two groups of the 300-800 km s-1 CMEs: (i) (very) gradually accelerating CMEs with acceleration below 10;m;s-2, and (ii) impu…
Internal kinematics and binarity of X-ray stars in the Pleiades open cluster
Makarov, V. V.; Robichon, N.
The classical convergent point analysis is implemented for the Pleiades stars with proper motions in the Tycho-2 Catalogue and X-ray fluxes measured by the ROSAT satellite. It is demonstrated that, with the standard astrometric errors as given in Tycho-2, strong X-ray sources in the cluster (log L_X > 29.1, where L_X is in erg s-1) e…
AGN in the XMM-Newton first-light image as probes for the interstellar medium in the LMC
Pietsch, W.; Haberl, F.; Filipović, M. D. +3 more
The XMM-Newton first-light image revealed X-ray point sources which show heavily absorbed power-law spectra. The spectral indices and the probable identification of a radio counterpart for the brightest source suggest AGN shining through the interstellar gas of the Large Magellanic Cloud (LMC). The column densities derived from the X-ray spectra i…
The nuclear starburst activity in the Seyfert 2 galaxy NGC 7679
Lei, S. J.; Huang, J. H.; Gu, Q. S. +3 more
We present our recent spectrophotometric results of the infrared luminous Seyfert 2 galaxy NGC 7679. We find compelling evidence for the presence of a recent nuclear starburst, revealed by the observations of a) the spectral features of high order Balmer absorption lines, b) the weak equivalent widths for CaIIK lambda 3933, CN lambda 4200, G-band …
Mid infrared polarisation of Ultraluminous Infrared Galaxies
Siebenmorgen, R.; Efstathiou, A.
The mid infrared polarisation properties of four Ultraluminous Infrared Galaxies (ULIRGs) have been investigated by broad band filter observations with the ISOCAM instrument on board the Infrared Space Observatory (ISO). The wavelength region from 5 to 18 mu m was selected where the emission from the putative torus peaks. We report detection of po…
On the determination of the light curve parameters of detached active binaries. I. The prototype RS Canum Venaticorum
Becciani, U.; Lanza, A. F.; Rodonò, M.
Photospheric cool spots are responsible for wave-like distortions observed in the wide-band light curves of close active binaries. They affect the determination of the photometric parameters in eclipsing systems making it necessary to accurately model the spot effects in order to estimate the true luminosity ratio, the fractionary radii and the in…