Search Publications
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…
Magnetic helicity accumulation and tilt angle evolution of newly emerging active regions
Zhang, H.; Yang, S.; Büchner, J.
Context: It has been known for years that there is a general dominance of negative (positive) helicity of active regions (ARs) in the northern (southern) solar hemisphere. For a better understanding of the role of helicity in the evolution of active regions, it is necessary to know more about the accumulation of helicity during the emergence of ac…
A forming disk at z ~ 0.6: collapse of a gaseous disk or major merger remnant?
Yang, Y.; Neichel, B.; Flores, H. +2 more
Context: Local spiral galaxies contain roughly two-thirds of the present-day stellar mass density. However, the formation process of disks is still poorly understood.
Aims: We present and analyze observations of J033241.88-274853.9 at z = 0.6679 to understand how its stellar disk was formed.
Methods: We combine multi-wavelength EIS, HST/AC…
The architecture of the GJ 876 planetary system. Masses and orbital coplanarity for planets b and c
Bean, J. L.; Seifahrt, A.
We present a combined analysis of previously published high-precision radial velocities and astrometry for the GJ 876 planetary system using a self-consistent model that accounts for the planet-planet interactions. Assuming the three planets so far identified in the system are coplanar, we find that including the astrometry in the analysis does no…
XMM-Newton observation of the persistent Be/NS X-ray binary pulsar RX J1037.5-5647 in a low luminosity state
Tiengo, A.; Mereghetti, S.; Sidoli, L. +2 more
The spectra of several X-ray binary pulsars display a clear soft excess, which in most cases can be described with a blackbody model, above the main power-law component. While in the high-luminosity sources it is usually characterized by low temperature (kT < 0.5 keV) and a large emission radius (R > 100 km), in the two persistent and low-lu…
High-precision multi-band measurements of the angular clustering of X-ray sources
Ebrero, J.; Carrera, F. J.; Watson, M. G. +2 more
Aims: We aim to study the large-scale structure of an extragalactic serendipitous X-ray survey with unprecedented accuracy thanks to the large statistics involved, and provide insight into the environment of AGN at the epochs when their space density declines (z ∼ 1{-}2).
Methods: In this paper we present the two-point angular correlation func…
Phase-resolved XMM-Newton observations of the massive WR+O binary WR 22
Gosset, E.; Nazé, Y.; Rauw, G. +2 more
Aims. To better understand the phenomenon of colliding winds in massive binary stars, we study the X-ray lightcurve of a WR+O system of the Carina region, a system well known for the high mass of its primary.
Methods: Phase-resolved X-ray observations of the massive WR+O binary system WR 22 were performed with the XMM-Newton facility. We obser…