Search Publications
Photocentric variability of quasars caused by variations in their inner structure: consequences for Gaia measurements
Jovanović, P.; Popović, L. Č.; Stalevski, M. +4 more
Context. We study the photocenter position variability caused by variations in the quasar inner structure. We consider the variability in the accretion disk emissivity and torus structure variability caused by the different illumination by the central source. We discuss the possible detection of these effects by Gaia. Observations of the photocent…
The circumstellar disk of HH 30. Searching for signs of disk evolution with multi-wavelength modeling
Wolf, S.; Guilloteau, S.; Dutrey, A. +1 more
Context. Circumstellar disks are characteristic for star formation and vanish during the first few Myr of stellar evolution. During this time planets are believed to form in the dense midplane by growth, sedimentation and aggregation of dust. Indicators of disk evolution, such as holes and gaps, can be traced in the spectral energy distribution (S…
The first outburst of the black-hole candidate MAXI J1836-194 observed by INTEGRAL, Swift, and RXTE
Capitanio, F.; Ferrigno, C.; Bozzo, E. +1 more
MAXI J1836-194 is a transient black-hole candidate discovered in outburst on 30 August 2011. We report on the available INTEGRAL, Swift, and RXTE observations performed in the direction of the source during this event before 55 864 MJD. Combining the broad band (0.6-200 keV) spectral and timing information obtained from these data with the results…
The ROSAT-ESO flux limited X-ray galaxy cluster survey (REFLEX II). I. Newly identified X-ray luminous clusters at z ≥ 0.2
Böhringer, H.; Chon, G.
We report 19 intermediate redshift clusters newly detected in the ROSAT All-Sky survey that are spectroscopically confirmed. They form a part of 911 objects in the REFLEX II cluster catalogue with a limiting flux of 1.8 × 10-12 erg/s/cm2 in the 0.1-2.4 keV ROSAT band at redshift z ≥ 0.2. In addition we report three clusters f…
Angular correlation functions of X-ray point-like sources in the full exposure XMM-LSS field
Chiappetti, L.; Pierre, M.; Gosset, E. +8 more
Aims: Our aim is to study the large-scale structure of different types of AGN using the medium-deep XMM-LSS survey.
Methods: We measure the two-point angular correlation function of 5700 and 2500 X-ray point-like sources over the 11 sq. deg. XMM-LSS field in the soft (0.5-2 keV) and hard (2-10 keV) bands. For the conversion from the angu…
Infrared excess around nearby red giant branch stars and Reimers law
Groenewegen, M. A. T.
Context. Mass loss is one of the fundamental properties of asymptotic giant branch (AGB) stars, but for stars with initial masses below ~1 M⊙, the mass loss on the first red giant branch (RGB) actually dominates mass loss on the AGB. Nevertheless, mass loss on the RGB is still often parameterised by a simple Reimers law in stellar evolu…
Globules and pillars seen in the [CII] 158 µm line with SOFIA
Hill, T.; Lebouteiller, V.; Cormier, D. +22 more
Molecular globules and pillars are spectacular features, found only in the interface region between a molecular cloud and an H II-region. Impacting far-ultraviolet (FUV) radiation creates photon-dominated regions (PDRs) on their surfaces that can be traced by typical cooling lines. With the GREAT receiver onboard SOFIA we mapped and spectrally res…
Dynamics of quiescent prominence fine structures analyzed by 2D non-LTE modelling of the Hα line
Heinzel, P.; Schmieder, B.; Gunár, S. +2 more
Aims: We analyze the dynamics of the prominence fine structures of a quiescent prominence observed on April 26, 2007 during a coordinated campaign of several spaceborne and ground-based instruments. We use Lyman spectra observed by SOHO/SUMER and the Hα line spectra obtained by MSDP spectrograph working at the Meudon Solar Tower.
Methods…
Detection of HF emission from the Orion Bar
Ossenkopf, V.; Nagy, Z.; Bergin, E. A. +3 more
Context. The clumpy density structure of photon-dominated regions is well established, but the physical properties of the clumps and of the surrounding interclump medium are only approximately known.
Aims: The aim of this paper is to constrain the physical and chemical conditions in the Orion Bar, a prototypical nearby photon-dominated region…
Ammonia and other parent molecules in comet 10P/Tempel 2 from Herschel/HIFI and ground-based radio observations
Küppers, M.; Hartogh, P.; Crovisier, J. +12 more
The Jupiter-family comet 10P/Tempel 2 was observed during its 2010 return with the Herschel Space Observatory. We present here the observation of the JK (10-00) transition of NH3 at 572 GHz in this comet with the Heterodyne Instrument for the Far Infrared (HIFI) of Herschel. We also report on radio obser…