Search Publications

The red and blue galaxy populations in the GOODS field: evidence for an excess of red dwarfs
DOI: 10.1051/0004-6361:20077959 Bibcode: 2008A&A...477..763S

Castellano, M.; Pentericci, L.; Fontana, A. +8 more

Aims: We study the evolution of the galaxy population up to z∼ 3 as a function of its colour properties. In particular, luminosity functions and luminosity densities were derived as a function of redshift for the blue/late and red/early populations.
Methods: We use data from the GOODS-MUSIC catalogue, which have typical magnitude limits z

2008 Astronomy and Astrophysics
eHST 27
Extremely massive young clusters in NGC 1365
DOI: 10.1051/0004-6361:20077621 Bibcode: 2008A&A...492....3G

Pantin, E.; Panuzzo, P.; Alloin, D. +5 more

Context: In a previous work, three bright mid-infrared/radio sources were discovered in the nuclear region of starburst/AGN galaxy NGC 1365.
Aims: The present study aims to confirm that these sources are indeed young and massive “embedded” clusters, and derive their physical parameters, such as extinction, age and mass.
Methods: Using ISAA…

2008 Astronomy and Astrophysics
eHST 26
CME liftoff with high-frequency fragmented type II burst emission
DOI: 10.1051/0004-6361:200810049 Bibcode: 2008A&A...490..357P

Vainio, R.; Pomoell, J.; Pohjolainen, S.

Aims: Solar radio type II bursts are rarely seen at frequencies higher than a few hundred MHz. Since metric type II bursts are thought to be signatures of propagating shock waves, it is of interest to know how these shocks, and the type II bursts, are formed. In particular, how are high-frequency, fragmented type II bursts created? Are there diffe…

2008 Astronomy and Astrophysics
SOHO 26
Abundances of planetary nebula NGC 2392
DOI: 10.1051/0004-6361:20079041 Bibcode: 2008A&A...481..393P

Pottasch, S. R.; Bernard-Salas, J.; Roellig, T. L.

The spectra of the planetary nebula NGC 2392 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope. The aim is to determine the chemical composition of this object. We also make use of IUE and ground based spectra. Abundances determined from the mid-infrared lines, which are insensit…

2008 Astronomy and Astrophysics
IUE 26
Infrared to X-ray observations of PKS 2155-304 in a low state
DOI: 10.1051/0004-6361:200809973 Bibcode: 2008A&A...484L..35F

Maraschi, L.; Covino, S.; Tagliaferri, G. +14 more

Aims: Our goal is to understand the nature of blazars and the mechanisms for the generation of high-energy γ-rays, through the investigation of the prototypical blazar PKS 2155{-}304, which shows complex behaviour.
Methods: We analyze simultaneous infrared-to-X-ray observations obtained with XMM-Newton and REM on November 7, 2006, when the sou…

2008 Astronomy and Astrophysics
XMM-Newton 26
Star cluster versus field star formation in the nucleus of the prototype starburst galaxy M 82
DOI: 10.1051/0004-6361:200809653 Bibcode: 2008A&A...484..711B

de Grijs, R.; Cerviño, M.; Barker, S.

We analyse high-resolution Hubble Space Telescope/Advanced Camera for Surveys imaging of the nuclear starburst region of M 82, obtained as part of the Hubble Heritage mosaic made of this galaxy, in four filters (Johnson-Cousins equivalent B, V, and I broad bands, and an Hα narrow-band filter), as well as subsequently acquired U-band images. We fin…

2008 Astronomy and Astrophysics
eHST 26
Time variability of X-ray sources in the M 31 centre field
DOI: 10.1051/0004-6361:20078858 Bibcode: 2008A&A...480..599S

Stiele, H.; Pietsch, W.; Haberl, F. +1 more

Aims:We present an extension to our XMM-Newton X-ray source catalogue of M 31 containing 39 newly found sources. In order to classify and identify more of the sources we search for X-ray time variability in XMM-Newton archival data of the M 31 centre field.
Methods: As a source list we used our extended ca…

2008 Astronomy and Astrophysics
XMM-Newton 26
Asteroid 2867 Steins. III. Spitzer Space Telescope observations, size determination, and thermal properties
DOI: 10.1051/0004-6361:20078996 Bibcode: 2008A&A...487.1187L

Jorda, L.; Lamy, P. L.; Barucci, M. A. +6 more

Context: Asteroid 2867 Steins is the first target of the Rosetta space mission with a flyby scheduled in September 2008.
Aims: An early characterization is needed to optimize the flyby parameters and the science operations, and to maximize the scientific return.
Methods: We used the infrared spectrograph (IRS) of the Spitzer Space Telescop…

2008 Astronomy and Astrophysics
Rosetta 26
Spectroscopy and multiband photometry of the afterglow of intermediate duration γ-ray burst GRB 040924 and its host galaxy
DOI: 10.1051/0004-6361:20078050 Bibcode: 2008A&A...481..319W

Hornstrup, A.; Vreeswijk, P. M.; Wijers, R. A. M. J. +19 more

Aims: We present optical photometry and spectroscopy of the afterglow and host galaxy of gamma-ray burst GRB 040924. This GRB had a rather short duration of T90 ~2.4 s, and a well sampled optical afterglow light curve. We aim to use this dataset to find further evidence that this burst is consistent with a massive star core-collapse pro…

2008 Astronomy and Astrophysics
eHST 26
The serendipituous discovery of a short-period eclipsing polar in 2XMMp
DOI: 10.1051/0004-6361:20079341 Bibcode: 2008A&A...485..787V

Watson, M. G.; Schwope, A.; Osborne, J. P. +3 more

We report the serendipituous discovery of the new eclipsing polar 2XMMp J131223.4+173659. Its striking X-ray light curve attracted immediate interest when we were visually inspecting the source products of the 2XMMp catalogue. This light curve revealed its likely nature as a magnetic cataclysmic variable of AM Herculis (or polar) type with an orbi…

2008 Astronomy and Astrophysics
XMM-Newton 26