Search Publications
X-ray eclipse time delays in 4U 2129+47
Campana, S.; Israel, G.; Stella, L. +8 more
Aims:4U 2129+47 was discovered in the early 80's and classified as an accretion disk corona source due to its broad and partial X-ray eclipses. The 5.24 h binary orbital period was inferred from the X-ray and optical light curve modulation, implying a late K or M spectral type companion star. The source entered a low state in 1983, during which th…
Solar energetic particle spectra from the SOHO-EPHIN sensor by application of regularization methods
Wimmer-Schweingruber, R. F.; Böhm, E.; Kharytonov, A.
Context: The Electron Proton Helium Instrument (EPHIN) on ESA's Solar and Heliospheric Observatory (SOHO) measures solar energetic electrons, protons, and alpha particles with a stack of six solid-state detectors forming a telescope. The energy deposit in these detectors must be inverted to derive the original energy of the incident particles, thu…
Correlation and asymmetry between solar flare hard X-ray footpoints: a statistical study
Ding, M. D.; Jin, M.
Aims:We study the correlation and asymmetry between solar flare hard X-ray footpoint time profiles that can be used to constrain the energy release and particle acceleration processes in solar flares.
Methods: We perform a statistical analysis of correlations and asymmetries of hard X-ray footpoints for 29 solar flares that were observed by th…
High resolution imaging of the early-type galaxy NGC 1380: an insight into the nature of extended extragalactic star clusters
Santiago, B. X.; Pastoriza, M. G.; Chies-Santos, A. L.
Context: NGC 1380 is a lenticular galaxy located near the centre of the Fornax Cluster, northeast of NGC 1399. The globular cluster system of this galaxy has hitherto only been studied from the ground. Recent studies of similar early-type galaxies, specially lenticular ones, reveal the existence of star clusters that apparently break up the tradit…
Constituents of the soft X-ray background
Sołtan, A. M.
Context: The X-ray background (XRB) is generated by various classes of objects and a variety of emission mechanisms. Relative contribution of individual components depends on energy.
Aims: The goal is to assess the integral emission of the major components of the soft XRB (extragalactic discrete sources dominated by active galactic nuclei (AGN…
A direct and differential imaging search for sub-stellar companions to ɛ Indi A
Henning, T.; Kürster, M.; Brandner, W. +7 more
We have carried out a direct and differential imaging search for sub-stellar companions to
A deep XMM-Newton X-ray observation of the Chamaeleon I dark cloud
Schmitt, J. H. M. M.; Robrade, J.
Context: Low-mass stars are known to exhibit strong X-ray emission during the early stages of evolution. Nearby star forming regions are ideal targets to study the X-ray properties of pre-main sequence stars.
Aims: A deep XMM-Newton exposure is used to investigate X-ray properties of the pre-main sequence population of the Chamaeleon I star fo…
Analysis of ISO SWS01 spectra of S stars
Wang, J.; Yang, X. H.; Chen, P. +1 more
The Infrared Space Observatory (ISO) Short-Wavelength Spectrometer (SWS01) plays an important role in studying properties of S stars. We reduce and analyze the SWS01 spectra of 17 S stars, and identify the candidate carriers of molecular absorption features. The ISO Spectral Analysis Package (ISAP) developed by the LWS and SWS Instrument Teams and…
High resolution γ-ray spectroscopy of flares on the east and west limbs of the Sun
Kiener, J.; Tatischeff, V.; Weidenspointner, G. +2 more
A new generation of Ge-based high-resolution gamma-ray spectrometers has allowed accurate measurements to be made of the profiles, widths and energies of the gamma-ray lines emitted in the impulsive phases of solar flares. Here we present measurements in two flares of the energies of the de-excitation lines of 12C and 16O at …
Multispectral analysis of solar EUV images: linking temperature to morphology
Auchère, F.; Dudok de Wit, T.
Context: Solar images taken simultaneously at different wavelengths in the EUV are widely used for understanding structures such as flares, coronal holes, loops, etc. The line-of-sight integration and the finite spectral resolution of EUV telescopes, however, hinders interpretation of these individual images in terms of temperature bands. Traditio…