Search Publications
The extended molecular envelope of the asymptotic giant branch star π1 Gruis as seen by ALMA. I. Large-scale kinematic structure and CO excitation properties
Lindqvist, M.; Höfner, S.; Wittkowski, M. +8 more
Context. The S-type asymptotic giant branch (AGB) star π1 Gru has a known companion at a separation of 2.̋7 (≈400 AU). Previous observations of the circumstellar envelope (CSE) show strong deviations from spherical symmetry. The envelope structure, including an equatorial torus and a fast bipolar outflow, is rarely seen in the AGB phase …
The molecular gas mass of M 33
Boquien, M.; Braine, J.; Calzetti, D. +15 more
Do some environments favor efficient conversion of molecular gas into stars? To answer this, we need to be able to estimate the H2 mass. Traditionally, this is done using CO observations and a few assumptions but the Herschel observations which cover the far-IR dust spectrum make it possible to estimate the molecular gas mass independen…
Water isotopologues in the circumstellar envelopes of M-type AGB stars
Olofsson, H.; Decin, L.; Lombaert, R. +3 more
Aims: In this study we intend to examine rotational emission lines of two isotopologues of water: H217O and H218O. By determining the abundances of these molecules, we aim to use the derived isotopologue - and hence oxygen isotope - ratios to put constraints on the masses of a sample of M-type AGB s…
A revised moving cluster distance to the Pleiades open cluster
Bouy, H.; Bouvier, J.; Teixeira, R. +3 more
Context. The distance to the Pleiades open cluster has been extensively debated in the literature over several decades. Although different methods point to a discrepancy in the trigonometric parallaxes produced by the HIPPARCOS mission, the number of individual stars with known distances is still small compared to the number of cluster members to …
In and out star formation in z 1.5 quiescent galaxies from rest-frame UV spectroscopy and the far-infrared
Cimatti, A.; Daddi, E.; Béthermin, M. +18 more
We present a sample of 34 spectroscopically confirmed BzK-selected 1011M⊙ quiescent galaxies (pBzK) in the COSMOS field. The targets were initially observed with VIMOS on the VLT to facilitate the calibration of the photometric redshifts of massive galaxies at z ≳ 1.5. Here we describe the reduction and analysis of the data, …
Herschel survey and modelling of externally-illuminated photoevaporating protoplanetary disks
Kamp, I.; Le Petit, F.; Goicoechea, J. R. +5 more
Context. Protoplanetary disks undergo substantial mass-loss by photoevaporation, a mechanism that is crucial to their dynamical evolution. However, the processes regulating the gas energetics have not so far been well constrained by observations.
Aims: We aim to study the processes involved in disk photoevaporation when it is driven by far-UV…
Stellar laboratories . VIII. New Zr iv-vii, Xe iv-v, and Xe vii oscillator strengths and the Al, Zr, and Xe abundances in the hot white dwarfs G191-B2B and RE 0503-289
Hoyer, D.; Rauch, T.; Werner, K. +5 more
Context. For the spectral analysis of high-resolution and high-signal-to-noise spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation.
Aims: To search for zirconium and xenon lines i…
Herschel observations of the Galactic H II region RCW 79
Liu, Hong-Li; Yuan, Jing-Hua; Wu, Yuefang +12 more
Context. Triggered star formation around H II regions could be an important process. The Galactic H II region RCW 79 is a prototypical object for triggered high-mass star formation.
Aims: We aim to obtain a census of the young stellar population observed at the edges of the H II region and to determine the properties of the young sources in o…
Polyaromatic disordered carbon grains as carriers of the UV bump: Far-UV to mid-IR spectroscopy of laboratory analogs
Dartois, E.; Giuliani, A.; Pino, T. +3 more
Context. A multiwavelength study of laboratory carbons with varying degrees of hydrogenation and sp2 hybridization is required to characterize the structure of the carbonaceous carriers of interstellar and circumstellar extinction.
Aims: We study the spectral properties of carbonaceous dust analogs from the far-ultraviolet to the m…
Recovering galaxy cluster gas density profiles with XMM-Newton and Chandra
Arnaud, M.; Pointecouteau, E.; Pratt, G. W. +6 more
We examined the reconstruction of galaxy cluster radial density profiles obtained from Chandra and XMM-Newton X-ray observations, using high quality data for a sample of twelve objects covering a range of morphologies and redshifts. By comparing the results obtained from the two observatories and by varying key aspects of the analysis procedure, w…