Search Publications
X-ray emission from MP Muscae: an old classical T Tauri star
Peres, G.; Argiroffi, C.; Maggio, A.
Aims:We study the properties of X-ray emitting plasma of
OVII and OVIII line emission in the diffuse soft X-ray background: heliospheric and galactic contributions
Ballet, J.; Lallement, R.; Acero, F. +2 more
Aims:We study the 0.57 keV (O VII triplet) and 0.65 keV (O VIII) diffuse emission generated by charge transfer collisions between solar wind (SW) oxygen ions and interstellar H and He neutral atoms in the inner Heliosphere. These lines which dominate the 0.3-1.0 keV energy interval are also produced by hot gas in the galactic halo (GH) and possibl…
An updated survey of globular clusters in M 31. II. Newly discovered bright and remote clusters
Bellazzini, M.; Galleti, S.; Federici, L. +2 more
Aims:We present the first results of a large spectroscopic survey of candidate globular clusters located in the extreme outskirts of the nearby M 31 galaxy. The survey is aimed at ascertaining the nature of the selected candidates to increase the sample of confirmed M 31 clusters lying more that 2° away from the center of the galaxy.
Methods: …
X-ray monitoring of optical novae in M 31 from July 2004 to February 2005
Stiele, H.; Pietsch, W.; Haberl, F. +9 more
Context: Optical novae have recently been identified as the major class of supersoft X-ray sources in M 31 based on ROSAT and early XMM-Newton and Chandra observations.
Aims: This paper reports on a search for X-ray counterparts of optical novae in M 31 based on archival Chandra HRC-I and ACIS-I as well as XMM-Newton observations of the galaxy…
Multiple protostellar systems. II. A high resolution near-infrared imaging survey in nearby star-forming regions
Duchêne, G.; Ghez, A. M.; Bontemps, S. +3 more
Context: Multiple systems are the product of protostellar core fragmentation. Studying their statistical properties in young stellar populations therefore probes the physical processes at play during star formation.
Aims: Our project endeavors to obtain a robust view of multiplicity among embedded Class I and Flat Spectrum protostars in a wide…
A statistical analysis of X-ray variability in pre-main sequence objects of the Taurus molecular cloud
Audard, M.; Güdel, M.; Micela, G. +5 more
Context: This work is part of a systematic X-ray survey of the Taurus star-forming complex with XMM-Newton.
Aims: We study the time series of all X-ray sources associated with Taurus members, to statistically characterize their X-ray variability, and compare the results to those for pre-main sequence stars in the Orion Nebula Cluster and to ex…
The blue plume population in dwarf spheroidal galaxies. Genuine blue stragglers or young stellar population?
Gullieuszik, M.; Momany, Y.; Held, E. V. +3 more
Aims:Blue stragglers (BSS) in the Milky Way field and globular/open clusters are thought to be the product of either primordial or collisional binary systems. In the context of dwarf spheroidal galaxies it is hard to firmly disentangle a genuine BSS population from young main sequence (MS) stars tracing a ∼ 1-2 Gyr old star forming episode.
Me…
X-ray/ultraviolet observing campaign of the Markarian 279 active galactic nucleus outflow: a close look at the absorbing/emitting gas with Chandra-LETGS
Kaastra, J. S.; Kriss, G. A.; Arav, N. +12 more
We present a Chandra-LETGS observation of the Seyfert 1 galaxy
X-ray emission from classical T Tauri stars: accretion shocks and coronae?
Liefke, C.; Schmitt, J. H. M. M.; Robrade, J. +1 more
Context: Classical T Tauri stars (CTTS) are surrounded by actively accreting disks. According to current models material falls along the magnetic field lines from the disk with more or less free-fall velocity onto the star, where the plasma heats up and generates X-rays.
Aims: We want to quantitatively explain the observed high energy emission…
Cosmic shear analysis of archival HST/ACS data. I. Comparison of early ACS pure parallel data to the HST/GEMS survey
Simon, P.; Heymans, C.; Schrabback, T. +9 more
Context: This is the first paper of a series describing our measurement of weak lensing by large-scale structure, also termed “cosmic shear”, using archival observations from the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST).
Aims: In this work we present results from a pilot study testing the capabilities of the …