Search Publications
Photometric variability of the Be star CoRoT-ID 102761769
Suárez, J. C.; Baglin, A.; Frémat, Y. +16 more
Context. Classical Be stars are rapid rotators of spectral type late O to early A and luminosity class V-III, which exhibit Balmer emission lines and often a near infrared excess originating in an equatorially concentrated circumstellar envelope, both produced by sporadic mass ejection episodes. The causes of the abnormal mass loss (the so-called …
The outflow in Mrk 509. A method to calibrate XMM-Newton EPIC-pn and RGS
Kaastra, J. S.; Cappi, M.; Costantini, E. +3 more
We analyzed three XMM-Newton observations of the Seyfert 1 galaxy Mrk 509, with the goal of detecting small variations in the ionized outflow properties. Measurements such as these are limited by the quality of the cross-calibration between RGS, the best instrument for characterizing the spectrum, and EPIC-pn, the best instrument for characterizin…
HESS J1632-478: an energetic relic
Tramacere, A.; Walter, R.; Pohl, M. +4 more
Aims: HESS J1632-478 is an extended and still unidentified TeV source in the galactic plane.
Methods: In order to identify the source of the very high energy emission and to constrain its spectral energy distribution, we used a deep observation of the field obtained with XMM-Newton together with data from Molonglo, Spitzer and Fermi to d…
XMM-Newton long-look observation of the narrow line Seyfert 1 galaxy PKS 0558-504. I. Spectral analysis
Papadakis, I. E.; Brinkmann, W.; Nicastro, F. +3 more
Context. PKS 0558-504 has been observed repeatedly by XMM-Newton as a calibration and performance verification (PV) target. In this work, we present results from the spectral analysis of a long XMM-Newton observation of the radio loud Narrow Line Seyfert 1 galaxy PKS 0558-504.
Aims: To study the soft excess component in this object, the spect…
A HIFI preview of warm molecular gas around χ Cygni: first detection of H2O emission toward an S-type AGB star
de Graauw, Th.; Olofsson, H.; Marston, A. P. +24 more
Aims: A set of new, sensitive, and spectrally resolved, sub-millimeter line observations are used to probe the warm circumstellar gas around the S-type AGB star χ Cyg. The observed lines involve high rotational quantum numbers, which, combined with previously obtained lower-frequency data, make it possible to study in detail the chemical and …
Orbital motion of the young brown dwarf companion TWA 5 B
Neuhäuser, R.; Schmidt, T. O. B.; Vogt, N. +1 more
Context. It is difficult to determine masses and test formation models for brown dwarfs, because they are always above the main sequence, so that there is a degeneracy between mass and age. However, for brown dwarf companions to normal stars, such determinations may be possible, because one can know the distance and age of the primary star. As a r…
Herschel observations of deuterated water towards Sgr B2(M)
Menten, K. M.; Martin, P. G.; Murphy, J. A. +53 more
Observations of HDO are an important complement for studies of water, because they give strong constraints on the formation processes - grain surfaces versus energetic process in the gas phase, e.g. in shocks. The HIFI observations of multiple transitions of HDO in Sgr B2(M) presented here allow the determination of the HDO abundance throughout th…
The O I] 1641 Å line as a probe of symbiotic star winds
Shore, S. N.; Wahlgren, G. M.
Aims: The neutral oxygen resonance λ1302 Å line can, if the optical depth is sufficiently high, de-excite by an intercombination transition at λ1641 Å to a metastable state. This has been noted in a number of previous studies but never systematically investigated as a diagnostic of the neutral red giant wind in symbiotic stars and symbiotic-l…
Multi-color, rotationally resolved photometry of asteroid 21 Lutetia from OSIRIS/Rosetta observations
Jorda, L.; Lamy, P. L.; Hviid, S. F. +2 more
Context. Asteroid 21 Lutetia is the second target of the Rosetta space mission. Extensive pre-encounter, space-, and ground-based observations are being performed to prepare for the flyby in July 2010.
Aims: The aim of this article is to accurately characterize the photometric properties of this asteroid over a broad spectral range from the u…
The Herschel revolution: Unveiling the morphology of the high-mass star-formation sites N44 and N63 in the LMC
Bernard, J. -P.; Okumura, K.; Madden, S. C. +21 more
Aims: We study the structure of the medium surrounding sites of high-mass star formation to determine the interrelation between the H ii regions and the environment from which they were formed. The density distribution of the surroundings is key in determining how the radiation of the newly formed stars interacts with the surroundings in a wa…