Search Publications

Hard X-ray flux from low-mass stars in the Cygnus OB2 association

Micela, G.; Drake, J. J.; Flaccomio, E. +1 more

Context: The Cygnus OB2 association, the central engine of the Cygnus X star-forming region, is the subject of an extensive INTEGRAL Key Project that will accumulate 6Ms of observations. Analysis of 2Ms of observations by De Becker and co-workers provides the most sensitive limit yet obtained on hard X-ray emission from the cluster.
Aims: We i…

A decade of X-ray astronomy with XMM-Newton. Commentary on: Jansen F., Lumb D., Altieri B., et al., 2001, A&A, 365, L1; Strüder L., Briel U., Dennerl K., et al., 2001, A&A, 365, L18; Turner M. J. L., Abbey A., Arnaud M., et al., 2001, A&A, 365, L27

Güdel, M.

INTEGRAL and Swift/XRT observations of IGR J16460+0849

Zhang, S.; Chen, Y. P.; Li, T. P. +2 more

Aims: IGR J16460+0849 is reported in the 3rd IBIS catalog with the shortest exposure of about 11 ks among all the detected sources, which makes it the most interesting target to be investigated with a deeper exposure. The currently available data have increased to an exposure time of a few hundred ks. This stimulates us to investigate the source a…

INTEGRAL and Swift/XRT observations of IGR J19405-3016

Torres, D. F.; Zhang, S.; Chen, Y. P. +3 more

Aims: IGR J19405-3016 is reported in the 3rd IBIS catalog as one of its lowest significance sources (~4.6σ under an exposure of about 371 ks). This leads to a caveat in multi-wavelength studies, although the source was identified in the optical as a Seyfert 1. The currently available INTEGRAL data on the source have increased to an exposure time o…

Evolution of asymptotic giant branch stars. II. Optical to far-infrared isochrones with improved TP-AGB models

Bressan, A.; Girardi, L.; Granato, G. L. +3 more

We present a large set of theoretical isochrones, whose distinctive features mostly reside on the greatly-improved treatment of the thermally-pulsing asymptotic giant branch (TP-AGB) phase. Essentially, we have coupled the TP-AGB tracks described in Paper I, at their stages of pre-flash quiescent H-shell burning, with the evolutionary tracks for t…

Extragalactic optical-infrared background radiation, its time evolution and the cosmic photon-photon opacity

Rodighiero, G.; Franceschini, A.; Vaccari, M.

Context: The background radiation in the optical and the infrared cause energy loss in the propagation of high energy particles through space. In particular, TeV observations with Cherenkov telescopes of extragalactic sources are influenced by the opacity effects due to the interaction of the very high-energy source photons with the background lig…

GMASS ultradeep spectroscopy of galaxies at z ~ 2. II. Superdense passive galaxies: how did they form and evolve?

Berta, S.; Cimatti, A.; Daddi, E. +13 more

Aims: The aim of this work is to investigate the physical, structural and evolutionary properties of old, passive galaxies at z > 1.4 and to place new constraints on massive galaxy formation and evolution.
Methods: We combine ultradeep optical spectroscopy from the GMASS project (Galaxy Mass Assembly ultradeep Spectroscopic Survey) with GOO…

Rayleigh scattering in the transit spectrum of HD 189733b

Pont, F.; Vidal-Madjar, A.; Lecavelier Des Etangs, A. +1 more

The transit spectrum of the exoplanet HD 189733b has recently been obtained between 0.55 and 1.05 µm. Here we present an analysis of this spectrum. We develop first-order equations to interpret absorption spectra. In the case of HD 189733b, we show that the observed slope of the absorption as a function of wavelength is characteristic of ext…

A catalog of galaxy clusters observed by XMM-Newton

Davis, D. S.; Mushotzky, R. F.; Kuntz, K. D. +1 more

Aims:We present a uniform catalog of the images and radial profiles of the temperature, abundance, and brightness for 70 clusters of galaxies observed by XMM-Newton.
Methods: We use a new “first principles” approach to the modeling and removal of the background components; the quiescent particle background, the cosmic diffuse emission, the sof…

The great observatories origins deep survey. VLT/FORS2 spectroscopy in the GOODS-South field: Part III

Popesso, P.; Cesarsky, C.; Stern, D. +15 more

Aims:We present the full data set of the spectroscopic campaign of the ESO/GOODS program in the GOODS-South field, obtained with the FORS2 spectrograph at the ESO/VLT.
Methods: Objects were selected as candidates for VLT/FORS2 observations primarily based on the expectation that the detection and measurement of their spectral features would be…