101 citations · 741 across the 32 of their papers we have counts for
14 papers · 1 filter
Resolved 24.5 micron emission from massive young stellar objects
W. J. de Wit, M. G. Hoare, T. Fujiyoshi +8
Massive young stellar objects (MYSO) are surrounded by massive dusty envelopes. Our aim is to establish their density structure on scales of ~1000 AU, i.e. a factor 10 increase in…
Towards micro-arcsecond spatial resolution with Air Cherenkov Telescope arrays as optical intensity interferometers
W. J. de Wit, S. LeBohec, J. A. Hinton +3
In this poster contribution we highlight the equivalence between an Imaging Air Cherenkov Telescope (IACT) array and an Intensity Interferometer for a range of technical requiremen…
Post-Red Supergiants
Rene Oudmaijer, Ben Davies, Willem-Jan de Wit +1
The yellow hypergiants are found in a stage between the massive Red Supergiants and the Wolf-Rayet stars. This review addresses current issues concerning the evolution of massive s…
Detection of the lithium depletion boundary in the young open cluster IC 4665
S. Manzi, S. Randich, W. J. de Wit +1
The so-called lithium depletion boundary (LDB) provides a secure and independent tool for deriving the ages of young open clusters.In this context, our goal is to determine members…
Resolving the ionized wind of the post-Red Supergiant IRC +10 420 with VLTI/AMBER
W. J. de Wit, R. D. Oudmaijer, M. A. T. Groenewegen +3
The paper investigates the milli-arcsecond scale structure of the present-day mass-loss of the post-Red Supergiant IRC+10420. We use three telescopes of the VLT Interferometer in c…
The potential for intensity interferometry with gamma-ray telescope arrays
W. J. de Wit, S. Le Bohec, J. A. Hinton +4
Intensity interferometry exploits a quantum optical effect in order to measure objects with extremely small angular scales. The first experiment to use this technique was the Narra…
Stellar Intensity Interferometry with Air Cherenkov Telescope arrays
S. Le Bohec, M. Daniel, W. J. de Wit +5
The present generation of ground-based Very High Energy (VHE) gamma-ray observatories consist of arrays of up to four large (> 12m diameter) light collectors quite similar to those…
Small Magellanic Cloud Be stars: colour-magnitude relations and mass-loss
W. J. de Wit, H. J. G. L. M. Lamers, J. B. Marquette +1
We present an analysis of optical lightcurves of Small Magellanic Cloud Be-type stars. Observations show that (1) optical excess flux is correlated with near-IR excess flux indicat…
The remarkable light and colour variability of Small Magellanic Cloud Be stars
W. J. de Wit, H. J. G. L. M. Lamers, J. B. Marquette +2
(Abridged) Some 240 blue stars in the Small Magellanic Cloud are investigated on their fantastic irregular continuum variability. We report here two results regarding these stars.…
A deep wide-field optical survey in the young open cluster Collinder 359
N. Lodieu, J. Bouvier, D. J. James +4
We present the first deep, optical, wide-field imaging survey of the young open cluster Collinder 359, complemented by near-infrared follow-up observations. This study is part of a…
Exploring the Lower Mass Function in the young open Cluster IC 4665
W. J. de Wit, J. Bouvier, F. Palla +8
We present a study of the young (30-100Myr) open cluster IC 4665 with the aim to determine the shape of the mass function well into the brown dwarf regime. We photometrically selec…
The Origin of Massive O-type Field Stars. Part I: A Search for Clusters
W. J. de Wit, L. Testi, F. Palla +2
We present a study aimed at clarifying the birthplace for 43 massive O-type field stars. In this first paper we present the observational part: a search for stellar clusters near t…
A Quest for PMS candidate stars at low metallicity: Variable HAe/Be and Be stars in the Small Magellanic Cloud
W. J. de Wit, J-P. Beaulieu, H. J. G. L. M. Lamers +3
We report the discovery of 5 new Herbig Ae/Be candidate stars in the Small Magellanic Cloud in addition to the 2 reported in Beaulieu et al. (2001). We discuss these 7 HAeBe candid…
Some results based on the EROS microlensing survey
J. P. Beaulieu, H. J. G. L. M. Lamers, W. J. de Wit
We will review some results based on the EROS and the on going EROS-2 microlensing surveys to search for dark matter in the Galactic halo via microlensing effects on LMC/SMC stars.…