Spectroscopic study of the variability of three northern Of+ supergiants (2009)
De Becker, M., Rauw, G., Linder, N.
The transition from early Of stars to WN type objects is poorly understood. O-type supergiants with emission lines (OIf+) are considered to be intermediate between these two classes. The scope of...
Perrier, C., Breysacher, J., Rauw, G.
We present a technique to determine the orbital and physical parameters of eclipsing eccentric Wolf-Rayet + O-star binaries, where one eclipse is produced by the absorption of the O-star light by the...
Rauw, G., Nazé, Y., Lajús, E. Fernández, Lanotte, A., Solivella, G. R., Sana, H., ...
We present the results of a spectroscopic monitoring campaign devoted to three O-type stars in the Carina nebula. We derive the full SB2 orbital solution of the binary system Tr 16-112, an...
Spectroscopic study of the O-type runaway supergiant HD 195592 (2009)
De Becker, M., Linder, N., Rauw, G.
The scope of this paper is to perform a detailed spectroscopic study of the northern O-type supergiant HD 195592. We use a large sample of high quality spectra in order to investigate its...
Mahy, L., Naze, Y., Rauw, G., Gosset, E., De Becker, M., Sana, H., ...
Aims. We present the results obtained from a long-term spectroscopic campaign devoted to the multiplicity of O-type stars in the young open cluster NGC2244 and in the Mon OB2 association. Methods....
De Becker, M., Blomme, R., Micela, G., Pittard, J. M., Rauw, G., Romero, G. E., ...
Several colliding-wind massive binaries are known to be non-thermal emitters in the radio domain. This constitutes strong evidence for the fact that an efficient particle acceleration process is at...
Dust formation by the colliding-wind WC5+O9 binary WR19 at periastron passage (2009)
Williams, P. M., Rauw, G., Van Der Hucht, K. A.
We present infrared photometry of the episodic dust-making Wolf-Rayet system WR19 (LS3), tracking its fading from a third observed dust-formation episode in 2007 and strengthening the view that these...
A multiwavelength investigation of the massive eclipsing binary Cyg OB2 #5 (2008)
Linder, N., Rauw, G., Manfroid, J., Damerdji, Y., De Becker, M., Eenens, P., ...
The properties of the early-type binary Cyg OB2 #5 have been debated for many years and spectroscopic and photometric investigations yielded conflicting results. We have attempted to constrain the...
High resolution optical spectroscopy of Plaskett's star (2008)
Linder, N., Rauw, G., Martins, F., Sana, H., De Becker, M., Gosset, E.
We present here the analysis of an extensive set of high resolution optical spectra of Plaskett's star (HD 47129). We use a disentangling method to separate the individual spectra of each star. We...
Spectroscopic and photometric variability of the O9.5Vp star HD93521 (2008)
Rauw, G., De Becker, M., Van Winckel, H., Aerts, C., Eenens, P., Lefever, K., ...
The line profile variability and photometric variability of the O9.5 Vp star HD93521 are examined in order to establish the properties of the non-radial pulsations in this star. Fourier techniques...
A binary signature in the non-thermal radio-emitter Cyg OB2 #9 (2008)
Naze, Y., De Becker, M., Rauw, G., Barbieri, C.
Aims: Non-thermal radio emission associated with massive stars is believed to arise from a wind-wind collision in a binary system. However, the evidence of binarity is still lacking in some cases,...
HD148937: a multiwavelength study of the third Galactic member of the Of?p class (2008)
Naze, Y., Walborn, N. R., Rauw, G., Martins, F., Pollock, A. M. T., Bond, H. E.
Three Galactic O-type stars belong to the rare class of Of?p objects: HD108, HD191612, and HD148937. The first two stars show a wealth of phenomena, including magnetic fields and strong X-ray...
The massive binary HD 152218 revisited: A new colliding wind system in NGC 6231 (2008)
Sana, H., Nazé, Y., O'Donnell, B., Rauw, G., Gosset, E.
We present the results of an optical and X-ray monitoring campaign on the short-period massive SB2 binary HD 152218. Combining our HiRes spectroscopic data with previous observations, we unveil the...
XMM-Newton X-ray study of early type stars in the Carina OB1 association (2007)
Antokhin, I. I., Rauw, G., Van Der Hucht, K. A., Brown, J. C.
X-ray properties of the stellar population in the Carina OB1 association are examined with special emphasis on early-type stars. Their spectral characteristics provide some clues to understanding the...
The LMC transition star R 84 and the core of the LH 39 OB association (2007)
Heydari-Malayeri Courbin, M. Heydari-malayeri, F. Courbin, G. Rauw, O. Esslinger, P. Magain
. On the basis of sub-arcsecond imaging obtained at the ESO NTT with SUSI and the ESO ADONIS adaptive optics system at the 3.6 m telescope, we resolve and study the core components of the LMC OB...
The investigation of particle acceleration in colliding-wind massive binaries with SIMBOL-X (2007)
De Becker, M., Rauw, G., Pittard, J. M., Blomme, R., Romero, G. E., Sana, H., ...
An increasing number of early-type (O and Wolf-Rayet) colliding wind binaries (CWBs) is known to accelerate particles up to relativistic energies. In this context, non-thermal emission processes such...
The Struve-Sahade effect in the optical spectra of O-type binaries I. Main-sequence systems (2007)
Linder, N., Rauw, G., Sana, H., De Becker, M., Gosset, E.
We present a spectroscopic analysis of four massive binary systems that are known or are good candidates to display the Struve-Sahade effect (defined as the apparent strengthening of the secondary...
The massive star binary fraction in young open clusters I. NGC 6231 revisited (2007)
Sana, H., Gosset, E., Naze, Y., Rauw, G., Linder, N.
We present the results of a long-term high-resolution spectroscopy campaign on the O-type stars in NGC 6231. We revise the spectral classification and multiplicity of these objects and we constrain...
De Becker, M., Rauw, G., Pittard, J. M., Sana, H., Stevens, I. R., Romero, G. E.
Aims: We analyze INTEGRAL-ISGRI data in order to probe the hard X-ray emission (above 20 keV) from point sources in the Cyg OB2 region and to investigate the putative non-thermal high-energy emission...
Towards an understanding of the Of?p star HD 191612: optical spectroscopy (2007)
Howarth, Ian D., Walborn, Nolan R., Lennon, Danny J., Puls, Joachim, Naze, Yael, Annuk, K., ...
We present extensive optical spectroscopy of the early-type magnetic star HD 191612 (O6.5f?pe-O8fp). The Balmer and HeI lines show strongly variable emission which is highly reproducible on a...
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Yu.A., Lebrun, F., Renaud, M., Terrier, R., ...
We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The JEM-X monitor and ISGRI...
An XMM-Newton view of the young open cluster NGC 6231 III. Optically faint X-ray sources (2007)
Sana, H., Rauw, G., Sung, H., Gosset, E.
We discuss the properties of the X-ray sources with faint optical counterparts in the very young open cluster NGC 6231. From their positions in the H-R diagram, we find that the bulk of these objects...
Constraining the fundamental parameters of the O-type binary CPD-41degr7733 (2007)
Sana, H., Rauw, G., Gosset, E.
Using a set of high-resolution spectra, we studied the physical and orbital properties of the O-type binary CPD-41 7733, located in the core of \ngc. We report the unambiguous detection of the...
Early-type stars in the core of the young open cluster Westerlund2 (2006)
Rauw, G., Manfroid, J., Gosset, E., Naze, Y., Sana, H., De Becker, M., ...
Aims. The properties of the early-type stars in the core of the Westerlund2 cluster are examined in order to establish a link between the cluster and the very massive Wolf-Rayet binary WR20a as well...
On the nature of the hard X-ray source IGR J2018+4043 (2006)
Bykov, A. M., Krassilchtchikov, A. M., Uvarov, Yu. A., Kennea, J. A., Pavlov, G. G., Dubner, G. M., ...
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multi-wavelength observations of the source field. The source, originally discovered in the 20-40...
On the nature of the hard X-ray source IGR J2018+4043 (2006)
Bykov, A. M., Krassilchtchikov, A. M., Uvarov, Yu. A., Kennea, J. A., Pavlov, G. G., Dubner, G. M., ...
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multi-wavelength observations of the source field. The source, originally discovered in the 20-40...
The first orbital solution for the massive colliding-wind binary HD93162 (=WR25) (2006)
Gamen, R., Gosset, E., Morrell, N., Niemela, V., Sana, H., Naze, Y., ...
Since the discovery, with the EINSTEIN satellite, of strong X-ray emission associated with HD93162 (=WR25), this object has been predicted to be a colliding-wind binary system. However,...
GCIRS16SW: a massive eclipsing binary in the Galactic Center (2006)
Martins, F., Trippe, S., Paumard, T., Ott, T., Genzel, R., Rauw, G., ...
We report on the spectroscopic monitoring of GCIRS16SW, an Ofpe/WN9 star and LBV candidate in the central parsec of the Galaxy. SINFONI observations show strong daily spectroscopic changes in the K...
An XMM-Newton view of the young open cluster NGC 6231 -- II. The OB star population (2006)
Sana, H., Rauw, G., Naze, Y., Gosset, E.
In this second paper, we pursue the analysis of the 180 ks XMM-Newton campaign towards the young open cluster NGC 6231 and we focus on its rich OB star population. We present a literature-based...
The atypical emission-line star Hen3-209 (2006)
Naze, Y., Rauw, G., Hutsemekers, D., Gosset, E., Manfroid, J., Royer, P.
We analyse observations, spanning 15 years, dedicated to the extreme emission-line object Hen3-209. Our photometric data indicate that the luminosity of the star undergoes marked variations with a...
De Becker, M., Rauw, G., Manfroid, J., Eenens, P.
Aims: We address the issue of the multiplicity of the three brightest early-type stars of the young open cluster IC1805, namely HD15570, HD15629 and HD15558. Methods: For the three stars, we measured...
An XMM-Newton view of the young open cluster NGC 6231 -- I. The catalogue (2006)
Sana, H., Gosset, E., Rauw, G., Sung, H.
This paper is the first of a series dedicated to the X-ray properties of the young open cluster NGC 6231. Our data set relies on an XMM-Newton campaign of a nominal duration of 180 ks and reveals...
On the nature of the hard X-ray source IGR J2018+4043 (2006)
Bykov, A. M., Krassilchtchikov, A. M., Uvarov, Yu. A., Kennea, J. A., Pavlov, G. G., Dubner, G. M., ...
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multi-wavelength observations of the source field. The source, originally discovered in the 20-40...
GCIRS 16SW: a massive eclipsing binary in the galactic center (2006)
Martins, F., Trippe, S., Paumard, T., Ott, T., Genzel, R., Rauw, G., ...
On the Nature of the Hard X-Ray Source IGR J2018+4043 (2006)
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Y.A., Kennea, J.A., Pavlov, G.G., Dubner, G.M., ...
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multiwavelength observations of the source field. The source, originally discovered in the 20-40...
On the Nature of the Hard X-Ray Source IGR J2018+4043 (2006)
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Y.A., Kennea, J.A., Pavlov, G.G., Dubner, G.M., ...
We found a very likely counterpart to the recently discovered hard X-ray source IGR J2018+4043 in the multiwavelength observations of the source field. The source, originally discovered in the 20-40...
Bykov, A. M., Krassilchtchikov, A. M., Uvarov, Yu. A., Lebrun, F., Renaud, M., Terrier, R., ...
We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The JEM-X monitor and ISGRI...
An exceptional X-ray view of the young open cluster NGC 6231: what XMM-Newton has taught us (2005)
Sana, H., Gosset, E., Rauw, G.
Considered as the core of the Sco OB1 association, the young open cluster NGC 6231 harbours a rich O-type star population. In 2001, the XMM-Newton satellite targeted the cluster for a nominal...
CPD-41deg7742: an unusual wind interaction (2005)
Sana, H., Gosset, E., Rauw, G., Antokhina, E., Royer, P., Manfroid, J., ...
We summarize the results of a multiwavelength observing campaign on the massive eclipsing binary CPD-41deg7742, another remarkable object in the young open cluster NGC 6231. Our campaign relies on...
The massive binary CPD-41 degrees 7742 - II. Optical light curve and X-ray observations (2005)
Sana, H, Antokhina, E, Royer, Pierre; U0037634, Manfroid, J, Gosset, E, Rauw, G, ...
In the first paper of this series, we presented a detailed high-resolution spectroscopic study of CPD - 41 degrees 7742, deriving for the first time an orbital solution for both components of the...
The massive binary CPD-41degr7742 II. Optical light curve and X-ray observations (2005)
Sana, H., Antokhina, E., Royer, P., Manfroid, J., Gosset, E., Rauw, G., ...
In the first paper of this series, we presented a detailed high-resolution spectroscopic study of CPD - 41degr7742, deriving for the first time an orbital solution for both components of the system....
Are WC9 Wolf-Rayet stars in colliding-wind binaries? (2005)
Williams, P. M., Van Der Hucht, K. A., Rauw, G.
We present results from a spectroscopic search for massive companions to dust-making Galactic WC9 stars as a step to testing the paradigm that dust formation in these systems requires colliding winds...
De Becker, M., Rauw, G., Blomme, R., Pittard, J. M., Stevens, I. R., Runacres, M. C.
We discuss the results of two XMM-Newton observations of the open cluster NGC6604 obtained in April and September 2002. We concentrate mainly on the multiple system HD167971 (O5-8V + O5-8V + (O8I))....
Naze, Y., Antokhin, I. I., Sana, H., Gosset, E., Rauw, G.
We present the analysis of an extensive set of high resolution spectroscopic observations of HD93161, a visual binary with a separation of 2 arcsec. HD93161 A is a spectroscopic binary, with both...
Non-thermal radio emission from O-type stars. I. HD 168112 (2005)
Blomme, R., Van Loo, S., De Becker, M., Rauw, G., Runacres, M. C., ...
We present a radio lightcurve of the O5.5 III(f+) star HD 168112, based on archive data from the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). The fluxes show considerable...
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Yu.A., Lebrun, F., Renaud, M., Terrier, R., ...
We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The JEM-X monitor and ISGRI...
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Yu.A., Lebrun, F., Renaud, M., Terrier, R., ...
We report the detection of hard X-ray emission from the field of the star-forming region NGC 6334 with the the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The JEM-X monitor and ISGRI...
NGC 6231: X-ray properties of the early-type star population (2004)
Sana, H., Naze, Y., Gosset, E., Rauw, G., Sung, H.
Based on a deep XMM-Newton observation of the young open cluster NGC 6231, we derive the main X-ray properties of its early-type star population. Among the 610 X-ray sources detected in the field, 42...
Hard X-ray Emission Clumps in the gamma-Cygni Supernova Remnant: an INTEGRAL-ISGRI View (2004)
Bykov, A. M., Krassilchtchikov, A. M., Uvarov, Yu. A., Bloemen, H., Chevalier, R. A., Gustov, M. Yu., ...
Spatially resolved images of the galactic supernova remnant G78.2+2.1 (gamma-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International...
Line profile variability in the spectra of Oef stars: II. HD192281, HD14442 and HD14434 (2004)
We present the very first analysis of the spectroscopic variability of the three rapidly rotating Oef stars HD192281 (O5(ef)), HD14442 (O5.5ef) and HD14434 (O6.5(ef)). Radial velocities of the HeII...
De Becker, M., Rauw, G., Manfroid, J.
We present the results of a spectroscopic campaign revealing that the non-thermal radio emitter Cyg OB2 #8A is an O6 + O5.5 binary system. We propose the very first orbital solution indicating a...
We present the results of an intensive spectroscopic campaign in the optical waveband revealing that Cyg OB2 #8A is an O6 + O5.5 binary system with a period of about 21.9 d. Cyg OB2 #8A is a bright...
De Becker, M., Rauw, G., Blomme, R., Waldron, W. L., Sana, H., Pittard, J. M., ...
We report the results of a multiwavelength study of the non-thermal radio emitter HD168112 (O5.5III(f^+)). The detailed analysis of two quasi-simultaneous XMM-Newton and VLA observations reveals...
WR20a: a massive cornerstone binary system comprising two extreme early-type stars (2004)
Rauw, G., De Becker, M., Naze, Y., Crowther, P. A., Gosset, E., Sana, H., ...
We analyse spectroscopic observations of WR20a revealing that this star is a massive early-type binary system with a most probable orbital period of \sim 3.675 days. Our spectra indicate that both...
An XMM-Newton observation of the massive binary HD159176 (2004)
De Becker, M., Rauw, G., Pittard, J. M., Antokhin, I. I., Stevens, I. R., Gosset, E., ...
We report the analysis of an XMM-Newton observation of the close binary HD159176 (O7V + O7V). The observed L_X/L_bol ratio reveals an X-ray luminosity exceeding by a factor ~ 7 the expected value for...
XMM-Newton observations of the giant HII region N11 in the LMC (2004)
Naze, Y., Antokhin, I. I., Rauw, G.
Using the sensitive XMM-Newton observatory, we have observed the giant HII region N11 in the LMC for \sim30 ks. We have detected several large areas of soft diffuse X-ray emission along with 37 point...
HD108: the mystery deepens with XMM-Newton observations (2004)
Naze, Y., Rauw, G., Vreux, J. M., De Becker, M.
In 2001, using a large spectroscopic dataset from an extensive monitoring campaign, we discovered that the peculiar Of star HD108 displayed spectacular line variations. This strange behaviour could...
A phase-resolved XMM-Newton Campaign on the Colliding Wind Binary HD 152248 (2004)
Sana, H., Stevens, I. R., Gosset, E., Rauw, G.
We report the first results of an XMM-Newton monitoring campaign of the NGC 6231 open cluster in the Sco OB1 association. This first paper focuses on the massive colliding wind binary HD 152248,...
WR 20a: A massive cornerstone binary system comprising two extreme early-type stars (2004)
Rauw, G., Becker, M. De, Naze, Y., Crowther, P.A., Gosset, E., Sana, H., ...
We analyse spectroscopic observations of WR 20a revealing that this star is a massive early-type binary system with a most probable orbital period of ~3.675 days. Our spectra indicate that both...
Hard X-ray emission clumps in the gamma-Cygni supernova remnant: An INTEGRAL-ISGRI view (2004)
Bykov, A.M., Krassilchtchikov, A.M., Uvarov, Y.A., Bloemen, H., Chevalier, R.A., Gustov, M.Y., ...
Spatially resolved images of the galactic supernova remnant G78.2+2.1 (gamma-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International...
Y. Nazé, I. I. Antokhin, G. Rauw, E. Gosset
Abstract. Using the sensitive XMM-Newton observatory, we have observed the giant H ii region N 11 in the LMC for ∼30 ks. We have detected several large areas of soft diffuse X-ray emission along...
WR bubbles and HeII emission (2003)
Naze, Y., Rauw, G., Manfroid, J.
We present the very first high quality images of the HeII 4686 emission in three high excitation nebulae of the Magellanic Clouds. A fourth high excitation nebula, situated around the WR star...
VLT observations of the highly ionized nebula around Brey2 (2003)
Naze, Y., Rauw, G., Manfroid, J.
We present the first high resolution HeII 4686 images of the high excitation nebula around the WR star Brey 2 in the LMC. This nebula presents a striking morphology: a small arc-like feature some...
XMM-Newton high-resolution x-ray spectroscopy of the Wolf-Rayet object WR25 (WN6HA+04F) (2003)
Raassen, A.J.J., Mewe, R., Antokhin, I.I., Rauw, G., Vreux, J.M., ...
(DOI: will be inserted by hand later) (2003)
Y. Nazé, I. I. Antokhin, G. Rauw, E. Gosset
XMM-Newton observations of the giant Hii region N 11 in the LMC ⋆
A first detailed study of the colliding wind WR+O binary WR 30a (2001)
Gosset, E, Royer, Pierre; U0037634, Rauw, G, Manfroid, J, Vreux, JM
We present a detailed, extensive investigation of the photometric and spectroscopic behaviour of WR 30a. This star is definitely a binary system with a period around 4.6 d. We propose the value P =...
Optical spectroscopy of X-Mega targets - II. The massive double-lined O-type binary HD 93205 (2001)
Morrell, NI, Barba, RH, Niemela, VS, Corti, MA, Colombo, JFA, Rauw, G, ...
A new high-quality set of orbital parameters for the O-type spectroscopic binary HD 93205 has been obtained combining echelle and coude CCD observations. The radial velocity orbits derived from the...
Morrell, N. I., Barba, R. H., Niemela, V. S., Corti, M. A., Colombo, J. F. Albacete, Rauw, G., ...
A new high-quality set of orbital parameters for the O-type spectroscopic binary HD93205 has been obtained combining echelle and coude CCD observations. The radial velocity orbits derived from the...
Compact star clusters of the LMC H II region N11 C (vol 361, pg 877, 2000) (2000)
Heydari-Malayeri, M, Royer, Pierre; U0037634, Rauw, G, Walborn, NR
Based on imaging and spectroscopy obtained at the ESO NTT telescope and using an efficient image analysis algorithm, we study the core of the LMC OB association LH 13, particularly the two compact...
Kahn, S. M., Leutenegger, M. A., Cottam, J., Rauw, G., ...
We present the first high resolution X-ray spectrum of the bright O4Ief supergiant star Zeta Puppis, obtained with the Reflection Grating Spectrometer on-board XMM-Newton. The spectrum exhibits...
Compact star clusters of the LMC HII region N11C (2000)
Heydari-Malayeri, M, Royer, Pierre; U0037634, Rauw, G, Walborn, NR
Based on imaging and spectroscopy obtained at the ESO NTT telescope and using an efficient image analysis algorithm, we study the core of the LMC OB association LH 13, particularly the two compact...
Compact star clusters of the LMC HII region N11C (2000)
Heydari-Malayeri, M., Royer, P., Rauw, G., Walborn, N. R.
Based on imaging and spectroscopy obtained at the ESO NTT telescope and using an efficient image analysis algorithm, we study the core of the LMC OB association LH13, particularly the two compact...
New observational results on the colliding wind WR+O binary WR 30a (1999)
Gosset, E, Royer, Pierre; U0037634, Rauw, G, Manfroid, J, Vreux, JM
Narrow-band photometry of the eclipsing WN7+O binary WR 22 (1999)
Royer, Pierre; U0037634, Rauw, G, Manfroid, J, Gosset, E, Vreux, JM
In the present paper, we discuss photometric observations of the February 1996 eclipse of the very massive WR+O binary WR 22. Our data were obtained with a set of narrow-band filters, specially...
The LMC transition star R84 and the core of the LH 39 OB association (1997)
Heydari-Malayeri, M., Courbin, F., Rauw, G., Esslinger, O., Magain, P.
On the basis of sub-arcsecond optical imaging we resolve and study the core components of the LMC OB association LH 39. The central star of the association, the rare transition object R84, is also...