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INTEGRAL, Swift, and RXTE observations of the 518 Hz accreting transient pulsar Swift J1749.4-2807
DOI: 10.1051/0004-6361/201015033 Bibcode: 2011A&A...525A..48F

Campana, S.; Stella, L.; Belloni, T. +7 more

Context. The burst-only source Swift J1749.4-2807 was discovered in a high X-ray-active state, during an INTEGRAL observations of the Galactic bulge on 2010 April 10. Pulsations at 518 Hz were discovered in the RXTE data, confirming previous suggestions of possible associations between burst-only sources and accreting millisecond X-ray pulsars. Th…

2011 Astronomy and Astrophysics
INTEGRAL 33
67P/Churyumov-Gerasimenko activity evolution during its last perihelion before the Rosetta encounter
DOI: 10.1051/0004-6361/201015515 Bibcode: 2011A&A...525A..36L

Lara, L. M.; Rodrigo, R.; Ip, W. -H. +1 more

Context. The comet 67P/Churyumov-Gerasimenko, target of the Rosetta Mission (ESA) was monitored from January to April 2009 during its last perihelion passage before the Rosetta spacecraft encounters the comet nucleus in May 2014. Photometric data were obtained only from January 25 to March 19, 2009 and they were used to monitor the comet gas and d…

2011 Astronomy and Astrophysics
Rosetta 33
On the Lx - L6 µm ratio as a diagnostic for Compton-thick AGN
DOI: 10.1051/0004-6361/201117400 Bibcode: 2011A&A...534A..23G

Vignali, C.; Gilli, R.; Ranalli, P. +6 more

As the mid-IR luminosity represents a good isotropic proxy of the AGN power, a low X-ray to mid-IR luminosity ratio is often claimed to be a reliable indicator of Compton-thick AGN. We assess the efficiency of the X-ray to mid-IR luminosity ratio diagnostic by examining the 12 µm IRAS AGN sample (intrinsic L2-10 keV > 1042…

2011 Astronomy and Astrophysics
ISO XMM-Newton 33
A2163: Merger events in the hottest Abell galaxy cluster. II. Subcluster accretion with galaxy-gas separation
DOI: 10.1051/0004-6361/201014907 Bibcode: 2011A&A...527A..21B

Arnaud, M.; Pratt, G. W.; Bourdin, H. +7 more

Located at z = 0.203, A2163 is a rich galaxy cluster with an intra-cluster medium (ICM) that exhibits extraordinary properties, including an exceptionally high X-ray luminosity, average temperature, and a powerful and extended radio halo. The irregular and complex morphology of its gas and galaxy structure suggests that this cluster has recently u…

2011 Astronomy and Astrophysics
XMM-Newton 33
First results of Herschel-SPIRE observations of Titan
DOI: 10.1051/0004-6361/201118304 Bibcode: 2011A&A...536L...2C

Hartogh, P.; Lellouch, E.; Moreno, R. +4 more

We investigate the composition of Titan's stratosphere from high-resolution submillimetric observations performed with the SPIRE instrument on the Herschel satellite. From the flux density spectrum measured in the 20 - 52 cm-1 interval at an apodized resolution of 0.08 cm-1, we determine the stratospheric abundances of CH

2011 Astronomy and Astrophysics
Herschel 32
Multiwavelength campaign on Mrk 509. V. Chandra-LETGS observation of the ionized absorber
DOI: 10.1051/0004-6361/201117067 Bibcode: 2011A&A...534A..40E

Kaastra, J. S.; Kriss, G. A.; Arav, N. +11 more

Context. We present here the results of a 180 ks Chandra-LETGS observation as part of a large multi-wavelength campaign on Mrk 509.
Aims: We study the warm absorber in Mrk 509 and use the data from a simultaneous HST-COS observation in order to assess whether the gas responsible for the UV and X-ray absorption are the same.
Methods: We a…

2011 Astronomy and Astrophysics
eHST 32
The cosmic far-infrared background buildup since redshift 2 at 70 and 160 microns in the COSMOS and GOODS fields
DOI: 10.1051/0004-6361/201015432 Bibcode: 2011A&A...525A..52J

Kneib, J. -P.; Aussel, H.; Le Floc'h, E. +10 more

Context. The cosmic far-infrared background (CIB) at wavelengths around 160 µm corresponds to the peak intensity of the whole extragalactic background light, which is being measured with increasing accuracy. However, the build up of the CIB emission as a function of redshift is still not well known.
Aims: Our goal is to measure the CIB …

2011 Astronomy and Astrophysics
Herschel 32
A spectroscopic investigation of early-type stars in the young open cluster Westerlund 2
DOI: 10.1051/0004-6361/201117000 Bibcode: 2011A&A...535A..40R

Nazé, Y.; Rauw, G.; Sana, H.

Context. The distance of the very young open cluster Westerlund 2, which contains the very massive binary system WR 20a and is likely associated with a TeV source, has been the subject of much debate.
Aims: We attempt a joint analysis of spectroscopic and photometric data of eclipsing binaries in the clus…

2011 Astronomy and Astrophysics
eHST 32
Non-LTE models for the gaseous metal component of circumstellar discs around white dwarfs
DOI: 10.1051/0004-6361/201116625 Bibcode: 2011A&A...530A...7H

Rauch, T.; Werner, K.; Nagel, T. +1 more

Context. Gaseous metal discs around single white dwarfs have been discovered recently. They are thought to develop from disrupted planetary bodies.
Aims: Spectroscopic analyses will allow us to study the composition of extrasolar planetary material. We investigate in detail the first object for which a gas disc was discovered (SDSS J122859.93…

2011 Astronomy and Astrophysics
eHST 31
The extinction map of the OMC-1 molecular cloud behind the Orion nebula
DOI: 10.1051/0004-6361/201116554 Bibcode: 2011A&A...533A..38S

Robberto, M.; Scandariato, G.; Pagano, I. +1 more

Context. The Orion nebula and its associated young stellar cluster are located at the front-side of the optically thick OMC-1 molecular cloud. In order to disentangle the cluster members from background contamination, it is important to know the extinction provided by the OMC-1, which is poorly known, the available measurements …

2011 Astronomy and Astrophysics
eHST 31