Search Publications

Could electron-positron annihilation lines in the Galactic center result from pulsar winds?
DOI: 10.1051/0004-6361:20053559 Bibcode: 2006A&A...446..943W

Wang, W.; Pun, C. S. J.; Cheng, K. S.

Observations of a strong and extended positron-electron annihilation line emission in the Galactic center (GC) region by the Spectrometer on the International Gamma-Ray Astrophysical Laboratory (SPI/INTEGRAL) are challenging to the existing models of positron sources in the Galaxy. In this paper, we study the possibility that pulsar winds in the G…

2006 Astronomy and Astrophysics
INTEGRAL 44
New γ Cassiopeiae-like objects: X-ray and optical observations of SAO 49725 and HD 161103
DOI: 10.1051/0004-6361:20054589 Bibcode: 2006A&A...454..265L

Haberl, F.; Motch, C.; Janot-Pacheco, E. +2 more

A growing number of early Be stars exhibit X-ray luminosities that are intermediate between those typical of early type stars and those emitted by most Be/X-ray binaries in quiescence. We report on XMM-Newton observations of two such Be stars, SAO 49725 and HD 161103, which were originally discovered in a syst…

2006 Astronomy and Astrophysics
XMM-Newton 43
Diagnostics for specific PAHs in the far-IR: searching neutral naphthalene and anthracene in the Red Rectangle
DOI: 10.1051/0004-6361:20065435 Bibcode: 2006A&A...456..161M

Joblin, C.; Toublanc, D.; Mulas, G. +1 more

Context: .In the framework of the interstellar polycyclic aromatic hydrocarbons (PAHs) hypothesis, far-IR skeletal bands are expected to be the fingerprints of single species in this class.
Aims: .We address the question of detectability of low energy PAH vibrational bands, with respect to spectral contrast and intensity ratio with "classical"…

2006 Astronomy and Astrophysics
ISO 42
The nuclear regions of NGC 7582 from [Ne II] spectroscopy at 12.8 µm - an estimate of the black hole mass
DOI: 10.1051/0004-6361:20053385 Bibcode: 2006A&A...460..449W

Siebenmorgen, R.; Wold, M.; Lacy, M. +1 more

We present a high-resolution (R≈16 000) spectrum and a narrow-band image centered on the [Ne II]12.8 µm line of the central kpc region of the starburst/Seyfert 2 galaxy NGC 7582. The galaxy has a rotating circum-nuclear starburst disk, shown at great detail at a diffraction-limited resolution of 0.4 arcsec (≈ 40 pc). The h…

2006 Astronomy and Astrophysics
eHST 42
XMM-Newton observation of the Be/neutron star system RX J0146.9+6121: a soft X-ray excess in a low luminosity accreting pulsar
DOI: 10.1051/0004-6361:20065107 Bibcode: 2006A&A...455..283L

Mereghetti, S.; La Palombara, N.

We report on the XMM-Newton observation of the Be/neutron star X-ray binary system RX J0146.9+6121, a long period (~23 m) pulsar in the NGC 663 open cluster. The X-ray luminosity decreased by a factor of two compared to the last observation carried out in 1998, reaching a level of ∼1×1034 erg s-1, the lowest ever observed in …

2006 Astronomy and Astrophysics
XMM-Newton 41
Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71. II. A search for intra-day variability at millimetre wavelengths with the IRAM 30 m telescope
DOI: 10.1051/0004-6361:20054649 Bibcode: 2006A&A...456..117A

Grewing, M.; Britzen, S.; Wagner, S. J. +12 more

We report on a densely time sampled polarimetric flux density monitoring of the BL Lac object S5 0716+71 at 86 GHz and 229 GHz. The source was observed with the IRAM 30 m telescope at Pico Veleta within a coordinated multi-frequency observing campaign, which was centred around a 500 ks INTEGRAL observation during November 10 to …

2006 Astronomy and Astrophysics
INTEGRAL 41
VIMOS-IFU survey of z ~ 0.2 massive galaxy clusters. I. Observations of the strong lensing cluster Abell 2667
DOI: 10.1051/0004-6361:20053384 Bibcode: 2006A&A...456..409C

Kneib, J. -P.; Jullo, E.; Richard, J. +3 more

We present extensive multi-color imaging and low-resolution VIMOS integral field unit (IFU) spectroscopic observations of the X-ray luminous cluster Abell 2667 (z=0.233). An extremely bright giant gravitational arc (z=1.0334 ± 0.0003) is easily identified as part of a triple image system, and other fainter multiple images are also revealed by the …

2006 Astronomy and Astrophysics
eHST 41
Detection of water ice grains after the DEEP IMPACT onto Comet 9P/Tempel 1
DOI: 10.1051/0004-6361:200600003 Bibcode: 2006A&A...448L..53S

Rodriguez-Pascual, P. M.; Schulz, R.; Lumb, D. +3 more

Context: Icy grains in the inner coma of a comet may play an important role in the energy balance and in the production of certain gas coma species. Their existence has therefore been assumed repeatedly to explain a variety of observed phenomena. However, owing to their extremely short life time no evidence for the presence of icy grains had been …

2006 Astronomy and Astrophysics
XMM-Newton 41
Seasonal variations of the martian CO over Hellas as observed by OMEGA/Mars Express
DOI: 10.1051/0004-6361:20065586 Bibcode: 2006A&A...459..265E

Bibring, J. -P.; Gondet, B.; Langevin, Y. +6 more

The OMEGA imaging spectrometer aboard Mars Express has been used to study the evolution of the CO abundance over the Hellas basin, as a function of the seasonal cycle. In spite of significant uncertainties, due to the low intensity of the (2-0) CO band at 2.3 µm, these data allow to search for spatial variations over Hellas, where the surfac…

2006 Astronomy and Astrophysics
MEx 41
Absolute motions of globular clusters. II. HST astrometry and VLT radial velocities in NGC 6397
DOI: 10.1051/0004-6361:20064960 Bibcode: 2006A&A...456..517M

Anderson, J.; Milone, A. P.; Bedin, L. R. +5 more

In this paper we present a new, accurate determination of the three components of the absolute space velocity of the Galactic globular cluster NGC 6397 (l≃338°, b≃-12°). We used three HST/WFPC2 fields with multi-epoch observations to obtain astrometric measurements of objects in three different fields in this cluster. The identification of 33 back…

2006 Astronomy and Astrophysics
eHST 40