Search Publications
Multiwavelength observations of a rich galaxy cluster at z ∼ 1. The HST/ACS colour-magnitude diagram
Böhringer, H.; Lidman, C.; Perlmutter, S. +12 more
Context: XMMU J1229+0151 is a rich galaxy cluster with redshift z=0.975 that was serendipitously detected in X-rays within the scope of the XMM-Newton Distant Cluster Project. Both HST/ACS observations in the i775 and z850 passbands and VLT/FORS2 spectroscopy were obtained, in addition to follow-up Near-Infrared (NIR) imaging…
Molecular gas in NUclei of GAlaxies (NUGA). XII. The head-on collision in NGC 1961
Tacconi, L. J.; Hunt, L. K.; Schinnerer, E. +6 more
We present high-resolution maps of the CO(1-0) and CO(2-1) emission from the LINER 2 galaxy NGC 1961. This galaxy is unusual among late-type (Sc) disk galaxies in having a very large radial extent and inferred dynamical mass. We propose a head-on collision scenario to explain the perturbed morphology of this galaxy - both the off-centered rings an…
Quantifying the contamination by old main-sequence stars in young moving groups: the case of the Local Association
Montes, D.; Micela, G.; López-Santiago, J.
Context: The associations and moving groups of young stars are excellent laboratories for investigating stellar formation in the solar neighborhood. Previous results have confirmed that a non-negligible fraction of old main-sequence stars is present in the lists of possible members of young stellar kinematic groups. A detailed study of the propert…
Integral field optical spectroscopy of a representative sample of ULIRGs. II. Two-dimensional kpc-scale extinction structure
Colina, L.; Arribas, S.; García-Marín, M.
Context: Ultraluminous infrared galaxies are merging systems characterized for containing large amounts of dust and emitting the bulk of their energy in the infrared. Dust affects several of the observed properties derived from optical and near-IR rest-frame data, such as the stellar morphology and the ionized gas distribution. Systematic analysis…
The optical counterparts of accreting millisecond X-ray pulsars during quiescence
Covino, S.; D'Avanzo, P.; Campana, S. +3 more
Context: Eight accreting millisecond X-ray pulsars (AMXPs) are known to date. Although these systems are well studied at high energies, very little information is available for their optical/NIR counterparts. Up to now, only two of them, SAX J1808.4-3658 and IGR J00291+5934, have a secure multi-band detection of their optical counterparts in quies…
Hydrogen Lyman-α and Lyman-β spectral radiance profiles in the quiet Sun
Marsch, E.; Curdt, W.; Tian, H. +1 more
Aims: We extend earlier work by studying the line profiles of the hydrogen Lyman-α and Lyman-β lines in the quiet Sun. They were obtained quasi-simultaneously in a raster scan with a size of about 150'' × 120'' near disk center.
Methods: The self-reversal depths of the Ly-α and Ly-β profiles. we are quantified by measuring the maximum spectral…
Ionization processes in the atmosphere of Titan. II. Electron precipitation along magnetic field lines
Gronoff, G.; Lilensten, J.; Modolo, R.
Context: The Cassini probe regularly passes the vicinity of Titan, providing new insights into particle precipitation by use of its electron and ion spectrometers. A discrepancy between precipitation models and observations of electron fluxes has been found. This discrepancy was suspected to be caused by the geometry of the magnetic field.
Aim…
Integral field optical spectroscopy of a representative sample of ULIRGs. I. The data
Colina, L.; Monreal-Ibero, A.; Arribas, S. +1 more
Context: Ultraluminous infrared galaxies (ULIRGs) are among the brightest objects in the local Universe. They are powered by strong star formation and/or an AGN. As a result of the merger process, they are also likely to be the progenitors of elliptical galaxies. The study of the structure and kinematics of samples of local ULIRGs is necessary to …
The first cyclotron harmonic of 4U 1538-52
Torrejón, J. M.; Camero-Arranz, A.; Kreykenbohm, I. +3 more
Context: Cyclotron resonant scattering features are an essential tool for studying the magnetic field of neutron stars. The fundamental line provides a measure of the field strength, while the harmonic lines provide information about the structure and configuration of the magnetic field. Until now only a handful of sources are known to display mor…
Genetic inversion of sparse disk-integrated photometric data of asteroids: application to Hipparcos data
Mottola, S.; Tanga, P.; Cellino, A. +2 more
Context: The development of techniques for the inversion of sparse disk-integrated photometric data of asteroids is a very urgent task, due to the imminent commencements of large sky surveys from both space (Gaia) and the ground (Pan-STARRS).
Aims: We developed a numerical algorithm for the inversion of sparse photometric data of asteroids. An…