Search Publications

A comprehensive study of large-scale structures in the GOODS-SOUTH field up to z ∼ 2.5
DOI: 10.1051/0004-6361/200811570 Bibcode: 2009A&A...501..865S

Fiore, F.; Castellano, M.; Pentericci, L. +14 more

Aims: The aim of the present paper is to identify and study the properties and galactic content of groups and clusters in the GOODS-South field up to z∼ 2.5, and to analyse the physical properties of galaxies as a continuous function of environmental density up to high redshift.
Methods: We used the deep (z850∼ 26), multi-wavelength…

2009 Astronomy and Astrophysics
eHST 44
The X17.2 flare occurred in NOAA 10486: an example of filament destabilization caused by a domino effect
DOI: 10.1051/0004-6361:200809887 Bibcode: 2009A&A...493..629Z

Guglielmino, S. L.; Romano, P.; Contarino, L. +6 more

Context: It is now possible to distinguish between two main models describing the mechanisms responsible for eruptive flares : the standard model, which assumes that most of the energy is released, by magnetic reconnection, in the region hosting the core of a sheared magnetic field, and the breakout model, which assumes reconnection occurs at firs…

2009 Astronomy and Astrophysics
SOHO 44
Properties of the nuclei and comae of 13 ecliptic comets from Hubble Space Telescope snapshot observations
DOI: 10.1051/0004-6361/200811462 Bibcode: 2009A&A...508.1045L

Jorda, L.; Lamy, P. L.; A'Hearn, M. F. +2 more

Context: Knowledge of the size distribution of cometary nuclei and, more generally, of their physical properties is important for constraining models of the formation and evolution of the Solar System.
Aims: We report on our on-going effort to determine the ensemble properties of comets based on our success in detecting the nuclei of active c…

2009 Astronomy and Astrophysics
eHST 44
The enigmatic X-rays from the Herbig star HD 163296: Jet, accretion, or corona?
DOI: 10.1051/0004-6361:200811007 Bibcode: 2009A&A...494.1041G

Schmitt, J. H. M. M.; Günther, H. M.

Context: Herbig Ae/Be stars (HAeBe) are pre-main sequence objects in the mass range 2 M < M* < 8 M. Their X-ray properties are uncertain and, as yet, unexplained.
Aims: We want to elucidate the X-ray generating mechanism in HAeBes.
Methods: We present an XMM-Newton observation of the HAeBe HD 163296…

2009 Astronomy and Astrophysics
XMM-Newton 44
The Compton-thick AGN in the Chandra Deep Field North
DOI: 10.1051/0004-6361/200912395 Bibcode: 2009A&A...507..747G

Georgakakis, A.; Georgantopoulos, I.; Rowan-Robinson, M. +1 more

We present X-ray spectral analysis of the brightest sources (f2{-10 keV} > 10-15 erg cm-2 s-1) in the Chandra Deep Field North. Our sample consists of 222 sources; for the vast majority (171) either a spectroscopic or a photometric redshift is available. Our goal is to discover the Compton-thick AGN i…

2009 Astronomy and Astrophysics
INTEGRAL 44
The orbital velocity anisotropy of cluster galaxies: evolution
DOI: 10.1051/0004-6361/200911757 Bibcode: 2009A&A...501..419B

Poggianti, B. M.; Biviano, A.

Context: In nearby clusters early-type galaxies follow isotropic orbits. The orbits of late-type galaxies are instead characterized by slightly radial anisotropy. Little is known about the orbits of the different populations of cluster galaxies at redshift z > 0.3.
Aims: We investigate the redshift evolution of the orbits of cluster galaxie…

2009 Astronomy and Astrophysics
eHST 43
An analysis of the transit times of CoRoT-1b
DOI: 10.1051/0004-6361/200912030 Bibcode: 2009A&A...506..369B

Bean, J. L.

The CoRoT satellite is expected to discover tens of new transiting exoplanets during its mission. For each of these planets there will be a resulting long, continuous sequence of transit times that can be used to search for perturbations arising from an additional planet in the system. I report the results from a study of the transit times for CoR…

2009 Astronomy and Astrophysics
CoRoT 43
A forming, dust-enshrouded disk at z = 0.43: the first example of a massive, late-type spiral rebuilt after a major merger?
DOI: 10.1051/0004-6361:200810488 Bibcode: 2009A&A...496..381H

Flores, H.; Hammer, F.; Puech, M. +4 more

By combining Ultra Deep Field imagery from HST/ACS with kinematics from VLT/GIRAFFE, we derive a physical model of distant galaxies in a way similar to that achievable for nearby galaxies. A significant part of the evolution in the density of cosmic star formation is related to the rapid evolution of both luminous IR galaxies (LIRGs) and Luminous …

2009 Astronomy and Astrophysics
eHST 43
The pulsations of the B5IVe star HD 181231 observed with CoRoT and ground-based spectroscopy
DOI: 10.1051/0004-6361/200911971 Bibcode: 2009A&A...506..143N

Baudin, F.; Poretti, E.; Michel, E. +25 more

Context: HD 181231 is a B5IVe star, which has been observed with the CoRoT satellite during ~5 consecutive months and simultaneously from the ground in spectroscopy and spectropolarimetry.
Aims: By analysing these data, we aim to detect and characterize as many pulsation frequencies as possible, to search for the presence of…

2009 Astronomy and Astrophysics
CoRoT 43
Discovery of slow X-ray pulsations in the high-mass X-ray binary 4U 2206+54
DOI: 10.1051/0004-6361:200810950 Bibcode: 2009A&A...494.1073R

Wilms, J.; Reig, P.; Torrejón, J. M. +3 more

Context: The source 4U 2206+54 is one of the most enigmatic high-mass X-ray binaries. In spite of intensive searches, X-ray pulsations have not been detected in the time range 10-3-103 s. A cyclotron line at ~30 keV has been suggested by various authors but never detected with significance. The stellar wind of the optical com…

2009 Astronomy and Astrophysics
Exosat INTEGRAL 43