Search Publications

Wind accretion in the massive X-ray binary 4U 2206+54: abnormally slow wind and a moderately eccentric orbit
DOI: 10.1051/0004-6361:20054206 Bibcode: 2006A&A...449..687R

Reig, P.; Torrejón, J. M.; Negueruela, I. +2 more

Massive X-ray binaries are usually classified by the properties of the donor star in classical, supergiant and Be X-ray binaries, the main difference being the mass transfer mechanism between the two components. The massive X-ray binary 4U 2206+54 does not fit in any of these groups, and deserves a detailed study to understand h…

2006 Astronomy and Astrophysics
IUE 46
Repetitive occurrence of explosive events at a coronal hole boundary
DOI: 10.1051/0004-6361:20053826 Bibcode: 2006A&A...446..327D

Doyle, J. G.; Popescu, M. D.; Taroyan, Y.

SUMER/SoHO data taken at a coronal hole boundary show a repetitive explosive event occurrence rate of around 3 min increasing to over 5 min towards the end of the activity. We suggest that the neighbouring oppositely directed closed and open field lines at the coronal hole boundary undergo repetitive reconnection seen as a sequence of explosive ev…

2006 Astronomy and Astrophysics
SOHO 46
VLT spectroscopy and non-LTE modeling of the C/O-dominated accretion disks in two ultracompact X-ray binaries
DOI: 10.1051/0004-6361:20053768 Bibcode: 2006A&A...450..725W

Rauch, T.; Werner, K.; Dreizler, S. +2 more

Aims.We present new medium-resolution high-S/N optical spectra of the ultracompact low-mass X-ray binaries 4U 0614+091 and 4U 1626-67, taken with the ESO Very Large Telescope. They are pure emission line spectra and the lines are identified as due to CII-IV and OII-III.
Methods: .Line identification is corroborated by first results from modeli…

2006 Astronomy and Astrophysics
eHST 46
Power spectrum of the SDSS luminous red galaxies: constraints on cosmological parameters
DOI: 10.1051/0004-6361:20065377 Bibcode: 2006A&A...459..375H

Hütsi, G.

In this paper we determine the constraints on cosmological parameters using the CMB data from the Wmap experiment together with the recent power spectrum measurement of the SDSS Luminous Red Galaxies (LRGs). Specifically, we focus on spatially flat, low matter density models with adiabatic Gaussian initial conditions. The spatial flatness is achie…

2006 Astronomy and Astrophysics
eHST 46
The size and albedo of Rosetta fly-by target 21 Lutetia from new IRTF measurements and thermal modeling
DOI: 10.1051/0004-6361:20053742 Bibcode: 2006A&A...447.1153M

Hora, J. L.; Mueller, M.; Adams, J. D. +3 more

Recent spectroscopic observations indicate that the M-type asteroid 21 Lutetia has a primitive, carbonaceous-chondrite-like (C-type) surface composition for which a low geometric albedo would be expected; this is incompatible with the IRAS albedo of 0.221± 0.020. From new thermal-infrared spectrophotometric measurements and detailed thermophysical…

2006 Astronomy and Astrophysics
Rosetta 46
Dynamics and evolution of an eruptive flare
DOI: 10.1051/0004-6361:20065065 Bibcode: 2006A&A...455.1123T

Maltagliati, L.; Teriaca, L.; Falchi, A. +2 more

Aims.We study the dynamics and the evolution of a C2.3 two-ribbon flare, developed on 2002 August 11, during the impulsive phase as well as during the long gradual phase. To this end we obtained multiwavelength observations using the CDS spectrometer aboard SOHO, facilities at the National Solar Observatory/Sacramento Peak, and the TRACE and RHESS…

2006 Astronomy and Astrophysics
SOHO 45
The absolute motion of the peculiar cluster NGC 6791
DOI: 10.1051/0004-6361:20066085 Bibcode: 2006A&A...460L..27B

Anderson, J.; Bedin, L. R.; King, I. R. +2 more

We present improved values of the three components of the absolute space velocity of the open cluster NGC 6791. One HST ACS/WFC field with two-epoch observations provides astrometric measurements of objects in a field containing the cluster center. Identification of 60 background galaxies with sharp nuclei allows us to determine an absolute refere…

2006 Astronomy and Astrophysics
eHST 45
Observations of the intense and ultra-long burst GRB 041219a with the Germanium spectrometer on INTEGRAL
DOI: 10.1051/0004-6361:20065203 Bibcode: 2006A&A...455..433M

McGlynn, S.; McBreen, S.; Foley, S. +5 more

Context.GRB 041219a is the brightest burst localised by INTEGRAL. The peak flux of 43 ph cm-2 s-1 (1.84 × 10-5 erg cm-2 s-1, 20 keV-8 MeV, 1 s integration) is greater than that for ~98% of all bursts and the T_90 duration of ~186 s (~20 keV-8 MeV) is longer than all but a small number of burst…

2006 Astronomy and Astrophysics
INTEGRAL 45
A close look into the carbon disk at the core of the planetary nebula CPD-56°8032
DOI: 10.1051/0004-6361:20054585 Bibcode: 2006A&A...455.1009C

Wolf, S.; Lopez, B.; Collioud, A. +7 more

Aims.We present high spatial resolution observations of the dusty core of the Planetary Nebula with Wolf-Rayet central star CPD-56°8032, for which indications of a compact disk have been found by HST/SITS observations.
Methods: .These observations were taken with the mid-infrared interferometer VLTI/MIDI in imaging mode providing a typical 30…

2006 Astronomy and Astrophysics
eHST 45
Global fitting of globular cluster age indicators
DOI: 10.1051/0004-6361:20065133 Bibcode: 2006A&A...456.1085M

Weiss, A.; Meissner, F.

Context: .Stellar models and the methods for the age determinations of globular clusters are still in need of improvement.
Aims: .We attempt to obtain a more objective method of age determination based on cluster diagrams, avoiding the introduction of biases due to the preference of one single age indicator.
Methods: .We compute new stella…

2006 Astronomy and Astrophysics
eHST 44