Search Publications

Evidence of unrelaxed IGM around IC 1262
DOI: 10.1051/0004-6361:20066156 Bibcode: 2007A&A...463..153T

Pietsch, W.; Wolter, A.; Breitschwerdt, D. +2 more

Aims:A peculiar morphology of the hot gas was discovered at the center of IC 1262 with the ROSAT HRI. Sensitive Chandra and XMM-Newton data were requested to investigate the characteristics of this structure to understand its nature.
Methods: We have exploited the high resolution and sensitivity of Chandra's ACIS-S to invest…

2007 Astronomy and Astrophysics
XMM-Newton 9
Accurate masses of low mass stars GJ 765.2AB (0.83 M + 0.76 M)
DOI: 10.1051/0004-6361:20066224 Bibcode: 2007A&A...464..635B

Weigelt, G.; Schertl, D.; Ségransan, D. +10 more

Context: Because of the lack of precise masses, the coverage of the main-sequence empirical mass-luminosity relation for stars in the mass range from 0.6 M to 0.9 M is incomplete. The nearby K-type visual and spectroscopic binary GJ 765.2 = MLR 224 is a good candidate for new reliable points in this significant part of the …

2007 Astronomy and Astrophysics
Hipparcos 9
UV flux distributions of γ Doradus stars
DOI: 10.1051/0004-6361:20065958 Bibcode: 2007A&A...472..241G

Caffau, E.; Gerbaldi, M.; Faraggiana, R.

Context: It seems that the recently identified class of pulsating stars, the γ Dor type-variables, includes objects with different metal abundances and a large percentage of binaries.
Aims: We looked for indicators of metal abundance peculiarities and stellar binarity in a sample of 40 confirmed γ Dor stars.
Methods: Absolute magnitudes fr…

2007 Astronomy and Astrophysics
Hipparcos 9
Radio burst from converging separatrices
DOI: 10.1051/0004-6361:20077544 Bibcode: 2007A&A...471L..37A

Mann, G.; Aurass, H.; Rausche, G.

Context: In a previous paper on the X17 flare October 28, 2003, we found, among other radio flare sources, one displaced at ≈0.2 R_⊙ north of the flaring AR 10486, away from the main Hα and hard X-ray flare emission. The source came to our attention due to its timing, its spatial displacement from the flaring active region, and due to the behavior…

2007 Astronomy and Astrophysics
SOHO 9
Optical detection of the radio supernova SN 2000ft in the circumnuclear region of the luminous infrared galaxy NGC 7469
DOI: 10.1051/0004-6361:20067043 Bibcode: 2007A&A...467..559C

Panagia, N.; Colina, L.; Díaz-Santos, T. +4 more

Context: (Ultra)Luminous Infrared Galaxies (ULIRGs) produce massive stars in large quantities in their central starburst regions. The expected rate of supernova explosions is, on average, about one per year. Detection of these supernovae in the expected numbers has proven elusive so far.
Aims: Illustrate the general benefits and limitations of…

2007 Astronomy and Astrophysics
eHST 9
Spectral variability analysis of an XMM-Newton observation of Ark 564
DOI: 10.1051/0004-6361:20066420 Bibcode: 2007A&A...465..107B

Papadakis, I. E.; Brinkmann, W.; Raeth, C.

Context: We present a spectral variability analysis of the X-ray emission of the Narrow Line Seyfert 1 galaxy Ark 564 using the data from a ~100 ks XMM-Newton observation.
Aims: Taking advantage of the high sensitivity of this long observation and the simple spectral shape of Ark 564, we determine accurately the spectral variability patterns i…

2007 Astronomy and Astrophysics
XMM-Newton 9
Cygnus X-3 transition from the ultrasoft to the hard state
DOI: 10.1051/0004-6361:20078160 Bibcode: 2007A&A...473..903B

Gehrels, N.; von Kienlin, A.; De Cesare, G. +8 more

Aims:The nature of Cygnus X-3 is still not understood well. This binary system might host a black hole or a neutron star. Recent observations by INTEGRAL have shown that Cygnus X-3 was again in an extremely ultrasoft state. Here we present our analysis of the transition from the ultrasoft state, dominated by blackbody radiation at soft X-rays plus…

2007 Astronomy and Astrophysics
INTEGRAL 8
Multicolour CCD measurements of visual double and multiple stars. III
DOI: 10.1051/0004-6361:20065639 Bibcode: 2007A&A...464..641L

Strigachev, A.; Lampens, P.; Duval, D.

Context: Recent CCD observations were performed in the period 1998-2004 for a large sample of visual double and multiple stars selected from the Hipparcos Catalogue and/or from the Gliese Catalogue of Nearby Stars.
Aims: Accurate astrometric and photometric data allowing us to characterise the individual components are provided. These data are…

2007 Astronomy and Astrophysics
Hipparcos 8
A compact dust shell in the symbiotic system HM Sagittae
DOI: 10.1051/0004-6361:20066642 Bibcode: 2007A&A...465..469S

Cruzalèbes, P.; Chesneau, O.; Sacuto, S. +1 more

Aims:We present high spatial resolution observations of the mid-infrared core of the dusty symbiotic system HM Sge.
Methods: The MIDI interferometer was used with the VLT Unit Telescopes and Auxiliary Telescopes providing baselines oriented from PA = 42° to 105°. The MIDI visibilities are compared with the ones predicted in …

2007 Astronomy and Astrophysics
ISO 8
XMM-Newton observation of the classical T Tauri star SU Aurigae and the surrounding field
DOI: 10.1051/0004-6361:20077110 Bibcode: 2007A&A...471..951F

Audard, M.; Pallavicini, R.; Franciosini, E. +1 more

Aims: We investigate the properties of the X-ray emitting plasma of the classical T Tauri star SU Aurigae and of other sources in the field of view.
Methods: We use XMM-Newton to obtain a high-resolution RGS spectrum of SU Aur as well as EPIC imaging data and low-resolution spectra of the star and of other X-ray sources in the surrounding fiel…

2007 Astronomy and Astrophysics
XMM-Newton 8