Search Publications
XMM-Newton observation of 4U 1820-30. Broad band spectrum and the contribution of the cold interstellar medium
Waters, L. B. F. M.; Kaastra, J. S.; Costantini, E. +6 more
We present an analysis of the bright X-ray binary 4U 1820-30, thet is based mainly on XMM-Newton-RGS data, in addition to complementary data from XMM-Newton-EPIC-pn, INTEGRAL, and Chandra-HETG, to investigate different aspects of the source. The broad band continuum is fitted well by a classical combination of black body and Comptonized emission. …
Spacecraft VLBI and Doppler tracking: algorithms and implementation
Molera Calvés, G.; Gurvits, L. I.; Duev, D. A. +3 more
Aims: We present the results of several multi-station Very Long Baseline Interferometry (VLBI) experiments conducted with the ESA spacecraft Venus Express as a target. To determine the true capabilities of VLBI tracking for future planetary missions in the solar system, it is necessary to demonstrate the accuracy of the method for existing op…
Accretion-related properties of Herbig Ae/Be stars. Comparison with T Tauris
Eiroa, C.; Montesinos, B.; Mora, A. +4 more
Context. The mass accretion rate M⊙;acc) is a key parameter that has not accurately been determined for a wide sample of Herbig Ae/Be (HAeBe) stars until recently.
Aims: We look for trends relating M⊙acc and the stellar ages (t), spectral energy distributions (SEDs), and disk masses for a sample of 38 HAeBe stars, compar…
Strong lensing by a node of the cosmic web. The core of MACS J0717.5+3745 at z = 0.55
Smail, I.; Kneib, J. -P.; Smith, G. P. +9 more
We present results of a strong-lensing analysis of MACS J0717.5+3745 (hereafter MACS J0717), an extremely X-ray luminous galaxy cluster at z = 0.55. Observations at different wavelengths reveal a complex and dynamically very active cluster, whose core is connected to a large scale filament extended over several Mpc. Using multi-passband imaging da…
Stochastic gravito-inertial modes discovered by CoRoT in the hot Be star HD 51452
Poretti, E.; Rainer, M.; Samadi, R. +24 more
Context. Be stars are rapidly rotating stars with a circumstellar decretion disk. They usually undergo pressure and/or gravity pulsation modes excited by the κ-mechanism, i.e. an effect of the opacity of iron-peak elements in the envelope of the star. In the Milky Way, p-modes are observed in stars that are hotter than or equal to the B3 spectral …
The Earliest Phases of Star formation (EPoS) observed with Herschel: the dust temperature and density distributions of B68
Henning, Th.; Krause, O.; Balog, Z. +13 more
Context. Isolated starless cores within molecular clouds can be used as a testbed to investigate the conditions prior to the onset of fragmentation and gravitational proto-stellar collapse.
Aims: We aim to determine the distribution of the dust temperature and the density of the starless core B68.
Methods: In the framework of the Hersche…
Dust coagulation processes as constrained by far-infrared observations
Abergel, A.; Bernard, J. -P.; Ristorcelli, I. +4 more
Aims: We develop a simple model of coagulated dust particles of two sizes (3.5 and 60 nm radius) to understand the nature and the effects of coagulation, which could explain the evolution of the far-infrared (FIR) dust opacity observed in the transition between the diffuse and the dense interstellar medium (ISM) (nH > 103
On the physical structure of IRC +10216. Ground-based and Herschel observations of CO and C2H
Waters, L. B. F. M.; Barlow, M. J.; de Koter, A. +17 more
Context. The carbon-rich asymptotic giant branch star IRC +10 216 undergoes strong mass loss, and quasi-periodic enhancements of the density of the circumstellar matter have previously been reported. The star's circumstellar environment is a well-studied and complex astrochemical laboratory, in which many molecular species have been proved to be p…
Interstellar matter and star formation in W5-E. A Herschel view
Abergel, A.; Roussel, H.; André, Ph. +7 more
Aims: We identify the young stellar objects (YSOs) present in the vicinity of the W5-E H ii region, and study the influence of this H ii region on the star formation process in its surrounding molecular material.
Methods: W5-E has been observed with the Herschel-PACS and -SPIRE photometers, as part of the HOBYS key program; maps have bee…
"TNOs are Cool": A survey of the trans-Neptunian region. VI. Herschel/PACS observations and thermal modeling of 19 classical Kuiper belt objects
Fornasier, S.; Hartogh, P.; Lellouch, E. +20 more
Context. Trans-Neptunian objects (TNO) represent the leftovers of the formation of the solar system. Their physical properties provide constraints to the models of formation and evolution of the various dynamical classes of objects in the outer solar system.
Aims: Based on a sample of 19 classical TNOs we determine radiometric sizes, geometri…