References of "De Becker, Michaël"
     in
Bookmark and Share    
Full Text
See detailNon-thermal Hard X-ray Emission from Colliding Wind Binary Systems
Khangulyan, Dmitry; Bosch-Ramon, Valenti; De Becker, Michaël ULg

Poster (2012, July)

Colliding-wind massive star binaries are known to produce strong shocks in their wind-wind interaction regions. The interaction region is the scenario of several physical processes, including strong ... [more ▼]

Colliding-wind massive star binaries are known to produce strong shocks in their wind-wind interaction regions. The interaction region is the scenario of several physical processes, including strong thermal X-ray emission and in several cases particle acceleration up to relativistic energies. The latter process is still poorly understood in these environments, and deserves a particular attention in stellar astrophysics. The investigation of particle acceleration is a critical aspect of high-energy astrophysics, especially at energies above 10 keV where non-thermal emission processes dominate. We discuss the possibility to detect the hard X-ray emission from WR147, a well-known particle accelerator, using Astro-H Hard X-ray Telescope (HXT) and Soft Gamma-Ray Detector (SGD), and to probe the particle acceleration process at work in its colliding-wind region. [less ▲]

Detailed reference viewed: 14 (1 ULg)
Full Text
See detailParticle acceleration in colliding-wind massive binaries: a relevant science case for ASTRO-H
De Becker, Michaël ULg; Khangulyan, Dmitry; Bosch-Ramon, Valenti

Poster (2012, July)

The strong stellar winds of massive stars in binary systems interact through shocks responsible for several phenomena, including significant particle acceleration up to relativistic energies. The ... [more ▼]

The strong stellar winds of massive stars in binary systems interact through shocks responsible for several phenomena, including significant particle acceleration up to relativistic energies. The existence of this relativistic particle population is mainly revealed through detection of bright synchrotron radio emission in the case of a few tens of systems. More recently, Suzaku observations revealed the existence of non-thermal X-rays in the case of two colliding-wind binaries (CWBs), confirming the prediction that inverse Compton scattering should be at work in these objects. In this context, the ASTRO-H mission constitutes the ideal tool to investigate non-thermal phenomena in hard X-rays (above 10 keV), where the well-known thermal emission from the shocked winds should not be significantly present. This poster gives an overview of this science case, and provides clues for the expected input of ASTRO-H in the study of these objects. [less ▲]

Detailed reference viewed: 19 (3 ULg)
Full Text
Peer Reviewed
See detail9 Sagittarii: uncovering an O-type spectroscopic binary with an 8.6 year period
Rauw, Grégor ULg; Sana, H.; Spano, M. et al

in Astronomy and Astrophysics (2012), 542

Context. The O-type object 9 Sgr is a well-known synchrotron radio emitter. This feature is usually attributed to colliding-wind binary systems, but 9 Sgr was long considered a single star. <BR /> Aims ... [more ▼]

Context. The O-type object 9 Sgr is a well-known synchrotron radio emitter. This feature is usually attributed to colliding-wind binary systems, but 9 Sgr was long considered a single star. <BR /> Aims: We have conducted a long-term spectroscopic monitoring of this star to investigate its multiplicity and search for evidence for wind-wind interactions. <BR /> Methods: Radial velocities are determined and analysed using various period search methods. Spectral disentangling is applied to separate the spectra of the components of the binary system. <BR /> Results: We derive the first ever orbital solution of 9 Sgr. The system is found to consist of an O3.5 V((f[SUP]+[/SUP])) primary and an O5-5.5 V((f)) secondary moving around each other on a highly eccentric (e = 0.7), 8.6 year orbit. The spectra reveal no variable emission lines that could be formed in the wind interaction zone in agreement with the expected properties of the interaction in such a wide system. <BR /> Conclusions: Our results provide further support to the paradigm of synchrotron radio emission from early-type stars being a manifestation of interacting winds in a binary system. Based on observations collected at the European Southern Observatory (La Silla, Chile and Cerro Paranal, Chile) and the San Pedro Mártir observatory (Mexico).Appendix A is available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A>The reduced spectra are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/542/A95">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/542/A95</A> [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
See detailAstrochemistry: a (very) brief introduction
De Becker, Michaël ULg

Conference (2012, May 23)

Detailed reference viewed: 13 (1 ULg)
Full Text
Peer Reviewed
See detailThe Struve-Sahade effect in the optical spectra of O-type binaries. I. Main-sequence systems (Corrigendum)
Linder, N.; Rauw, Grégor ULg; Sana, H. et al

in Astronomy and Astrophysics (2012), 541

Not Available.

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailEvidence for a physically bound third component in HD 150136
Mahy, Laurent ULg; Gosset, Eric ULg; Sana, H et al

in Astronomy and Astrophysics (2012), 540

Context. HD 150136 is one of the nearest systems harbouring an O3 star. Although this system was considered for a long time as a binary, more recent investigations have suggested the possible existence of ... [more ▼]

Context. HD 150136 is one of the nearest systems harbouring an O3 star. Although this system was considered for a long time as a binary, more recent investigations have suggested the possible existence of a third component. <BR /> Aims: We present a detailed analysis of HD 150136 to test its triple nature. In addition, we investigate the physical properties of the individual components of this system. <BR /> Methods: We analysed high-resolution, high signal-to-noise data collected through multi-epoch runs spread over ten years. We applied a disentangling program to refine the radial velocities and to obtain the individual spectra of each star. With the radial velocities, we computed the orbital solution of the inner system, and we describe the main properties of the orbit of the outer star such as the preliminary mass ratio, the eccentricity, and the orbital-period range. With the individual spectra, we determined the stellar parameters of each star by means of the CMFGEN atmosphere code. <BR /> Results: We offer clear evidence that HD 150136 is a triple system composed of an O3V((f[SUP]∗[/SUP]))-3.5V((f[SUP]+[/SUP])), an O5.5-6V((f)), and an O6.5-7V((f)) star. The three stars are between 0-3 Myr old. We derive dynamical masses of about 64, 40, and 35 M[SUB]&sun;[/SUB] for the primary, the secondary and the third components by assuming an inclination of 49° (sin[SUP]3[/SUP]i = 0.43). It currently corresponds to one of the most massive systems in our galaxy. The third star moves with a period in the range of 2950 to 5500 d on an outer orbit with an eccentricity of at least 0.3. However, because of the long orbital period, our dataset is not sufficient to constrain the orbital solution of the tertiary component with high accuracy. <BR /> Conclusions: We confirm there is a tertiary star in the spectrum of HD 150136 and show that it is physically bound to the inner binary system. This discovery makes HD 150136 the first confirmed triple system with an O3 primary star. Table 1 is available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A> [less ▲]

Detailed reference viewed: 16 (0 ULg)
See detailThe long period eccentric orbit of the particle accelerator HD167971 revealed by long baseline interferometry
De Becker, Michaël ULg

Conference (2012, March 12)

Particle acceleration and non-thermal emission processes in colliding-wind massive binaries constitute key issues in massive stars physics. The investigation of such processes requires a good knowledge of ... [more ▼]

Particle acceleration and non-thermal emission processes in colliding-wind massive binaries constitute key issues in massive stars physics. The investigation of such processes requires a good knowledge of their stellar, stellar wind and orbital parameters. In this short contribution, I will present the latest results related to the case of HD167971, a system recently resolved by the VLTI. The information on the separation and on the luminosity ratio derived from these observations will also be discussed in the context of the so-called 'standard scenario' for particle acceleration and non-thermal processes in massive stars. [less ▲]

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailTests with a Carlina-type diluted telescope. Primary coherencing
Le Coroller, H.; Dejonghe, J.; Regal, X. et al

in Astronomy and Astrophysics (2012), 539

Aims: Studies are under way to propose a new generation of post-VLTI interferometers. The Carlina concept studied at the Haute-Provence Observatory is one of the proposed solutions. It consists in an ... [more ▼]

Aims: Studies are under way to propose a new generation of post-VLTI interferometers. The Carlina concept studied at the Haute-Provence Observatory is one of the proposed solutions. It consists in an optical interferometer configured like a diluted version of the Arecibo radio telescope: above the diluted primary mirror made of fixed cospherical segments, a helium balloon (or cables suspended between two mountains), carries a gondola containing the focal optics. Since 2003, we have been building a technical demonstrator of this diluted telescope. First fringes were obtained in May 2004 with two closely-spaced primary segments and a CCD on the focal gondola. We have been testing the whole optical train with three primary mirrors. The main aim of this article is to describe the metrology that we have conceived, and tested under the helium balloon to align the primary mirrors separate by 5-10 m on the ground with an accuracy of a few microns. Methods: Getting stellar fringes using delay lines is the main difficulty for astronomical interferometers. Carlina does not use delay lines, but the primary segments have to be positioned on a sphere i.e. coherencing the primary mirrors. As described in this paper, we used a supercontinuum laser source to coherence the primary segments. We characterize the Carlina's performances by testing its whole optical train: servo loop, metrology, and the focal gondola. Results: The servo loop stabilizes the mirror of metrology under the helium balloon with an accuracy better than 5 mm while it moves horizontally by 30 cm in open loop by 10-20 km/h of wind. We have obtained the white fringes of metrology; i.e., the three mirrors are aligned (cospherized) with an accuracy of ≈1 μm. We show data proving the stability of fringes over 15 min, therefore providing evidence that the mechanical parts are stabilized within a few microns. This is an important step that demonstrates the feasibility of building a diluted telescope using cables strained between cliffs or under a balloon. Carlina, like the MMT or LBT, could be one of the first members of a new class of telescopes named diluted telescopes. [less ▲]

Detailed reference viewed: 18 (3 ULg)
Full Text
Peer Reviewed
See detailThe Non-thermal Radio Emitter HD 93250 Resolved by Long Baseline Interferometry
Sana, H.; Le Bouquin, J.-B.; De Becker, Michaël ULg et al

in Astrophysical Journal Letters (2011), 740

As the brightest O-type X-ray source in the Carina nebula, HD 93250 (O4 III(fc)) is X-ray overluminous for its spectral type and has an unusually hard X-ray spectrum. Two different scenarios have been ... [more ▼]

As the brightest O-type X-ray source in the Carina nebula, HD 93250 (O4 III(fc)) is X-ray overluminous for its spectral type and has an unusually hard X-ray spectrum. Two different scenarios have been invoked to explain its X-ray properties: wind-wind interaction and magnetic wind confinement. Yet, HD 93250 shows absolutely constant radial velocities over timescales of years suggesting either a single star, a binary system seen pole-on view or a very long period, and/or highly eccentric system. Using the ESO Very Large Telescope Interferometer, we resolved HD 93250 as a close pair with similar components. We measured a near-infrared flux ratio of 0.8 ± 0.1 and a separation of (1.5 ± 0.2) × 10-3 arcsec. At the distance of Carina, this corresponds to a projected physical distance of 3.5 AU. While a quantitative investigation would require a full characterization of the orbit, the binary nature of HD 93250 allows us to qualitatively explain both its X-ray flux and hardness and its non-thermal radio emission in the framework of a colliding wind scenario. We also discuss various observational biases. We show that, due to line blending of two similar spectral components, HD 93250 could have a period as short as 1 to several years despite the lack of measurable radial velocity variations. [less ▲]

Detailed reference viewed: 11 (1 ULg)
Full Text
See detailNon-thermal radio emission from colliding-wind binaries: modelling Cyg OB2 No. 8A and No. 9
Volpi, Delia; Blomme, Ronny; De Becker, Michaël ULg et al

in Neiner, Coralie; Wade, G.; Meynet, G. (Eds.) et al Active OB stars: structure, evolution, mass loss and critical limits (2011, July 01)

Some OB stars show variable non-thermal radio emission. The non-thermal emission is due to synchrotron radiation that is emitted by electrons accelerated to high energies. The electron acceleration occurs ... [more ▼]

Some OB stars show variable non-thermal radio emission. The non-thermal emission is due to synchrotron radiation that is emitted by electrons accelerated to high energies. The electron acceleration occurs at strong shocks created by the collision of radiatively-driven stellar winds in binary systems. Here we present results of our modelling of two colliding wind systems: Cyg OB2 No. 8A and Cyg OB2 No. 9. [less ▲]

Detailed reference viewed: 17 (1 ULg)
Full Text
See detailThe latest developments on Of?p stars
Nazé, Yaël ULg; ud-Doula, Asif; Spano, Maxime et al

in Neiner, Coralie; Wade, G.; Meynet, G. (Eds.) et al Active OB stars: structure, evolution, mass loss and critical limits (2011, July 01)

In recent years several in-depth investigations of the three prototypical Of?p stars were undertaken, revealing their peculiar properties. To clarify some of the remaining questions, we have continued our ... [more ▼]

In recent years several in-depth investigations of the three prototypical Of?p stars were undertaken, revealing their peculiar properties. To clarify some of the remaining questions, we have continued our monitoring of the prototypical Of?p trio. HD 108 has now reached its quiescent, minimum-emission state, for the first time in 50-60yrs, while new echelle spectra of HD 148937 confirm the presence in several H and He lines of the 7d variations detected previously only in the Hα line. A new XMM observation of HD 191612 clearly shows that its X-ray emission is not modulated by the orbital period of 1542d, but the high-energy variations are rather compatible with the 538d period of the optical changes - it is thus not of colliding-wind origin but linked to the phenomena responsible for the spectral/photometric variations, though our current MHD simulations remain at odds with the observational properties. [less ▲]

Detailed reference viewed: 15 (2 ULg)
See detailInvestigation of the physics of wind interactions in colliding-wind massive binaries through XMS high resolution X-ray spectroscopy
De Becker, Michaël ULg

Conference (2011, June 14)

Binary systems made of two massive stars offer the opportunity to investigate the physics of quite extreme stellar environments. The powerful stellar winds collide, producing so-called wind interaction ... [more ▼]

Binary systems made of two massive stars offer the opportunity to investigate the physics of quite extreme stellar environments. The powerful stellar winds collide, producing so-called wind interaction regions, and the shocked gas is heated up to temperatures that can reach values as high as several tens of MK, leading to the production of copious amounts of thermal X-rays. The properties of the X-ray spectrum of such systems are intimately related to the orbitally modulated physical conditions in the wind interaction region. The study of the hydrodynamics of the colliding-wind phenomenon is a crucial issue in the sense that it constitutes the basement for the study of higher level physical processes at work in these systems, such as particle acceleration or even dust production. High-resolution X-ray spectroscopy with ATHENA/XMS is undoubtedly expected to be the most powerful tool to probe the physics of such environments over the next two decades, allowing a detailed confrontation to state-of-the-art theoretical models aiming at simulating the complex physics of colliding-wind massive binaries (CWBs). [less ▲]

Detailed reference viewed: 12 (1 ULg)
See detailLong baseline interferometry applied to the study of colliding-wind massive binaries: current status and prospects for the near future
De Becker, Michaël ULg

Conference (2011, April 04)

Massive binaries are important laboratories to investigate science topics related to stellar astrophysics. In particular, colliding winds in some massive binaries are known to produce strong X-ray ... [more ▼]

Massive binaries are important laboratories to investigate science topics related to stellar astrophysics. In particular, colliding winds in some massive binaries are known to produce strong X-ray emission, to accelerate particles, and to act as nucleation site for dust particles. Recent advances in the development of interferometric instruments coupled to long baseline facilities such as the VLTI allow us to observe astronomical targets at the milli-arcsecond scale. In the context of the study of colliding-wind binaries, this tool is likely to provide crucial information. I will briefly discuss ongoing observation campaigns aiming at using such interferometric facilities in the purpose to study the physics of colliding-wind binaries. [less ▲]

Detailed reference viewed: 9 (0 ULg)
Full Text
See detailThe COSPIX mission: focusing on the energetic and obscured Universe
Ferrando, P.; Goldwurm, A.; Laurent, P. et al

in Rieger, F.; van Eldik, C. (Eds.) 25th Texas Symposium on Relativistic Astrophysics (2011, April 01)

Tracing the formation and evolution of all supermassive black holes, including the obscured ones, understanding how black holes influence their surroundings and how matter behaves under extreme conditions ... [more ▼]

Tracing the formation and evolution of all supermassive black holes, including the obscured ones, understanding how black holes influence their surroundings and how matter behaves under extreme conditions, are recognized as key science objectives to be addressed by the next generation of instruments. These are the main goals of the COSPIX proposal, made to ESA in December 2010 in the context of its call for selection of the M3 mission. In addition, COSPIX, will also provide key measurements on the non thermal Universe, particularly in relation to the question of the acceleration of particles, as well as on many other fundamental questions as for example the energetic particle content of clusters of galaxies. COSPIX is proposed as an observatory operating from 0.3 to more than 100 keV. The payload features a single long focal length focusing telescope offering an effective area close to ten times larger than any scheduled focusing mission at 30 keV, an angular resolution better than 20 arcseconds in hard X-rays, and polarimetric capabilities within the same focal plane instrumentation. In this paper, we describe the science objectives of the mission, its baseline design, and its performances, as proposed to ESA. [less ▲]

Detailed reference viewed: 13 (3 ULg)
Full Text
Peer Reviewed
See detailXMM-Newton observation of the enigmatic object WR 46
Gosset, Eric ULg; De Becker, Michaël ULg; Nazé, Yaël ULg et al

in Astronomy and Astrophysics (2011), 527

Aims: To further investigate the nature of the enigmatic object WR 46 and better understand the X-ray emission in massive stars and in their evolved descendants, we observed this variable object for more ... [more ▼]

Aims: To further investigate the nature of the enigmatic object WR 46 and better understand the X-ray emission in massive stars and in their evolved descendants, we observed this variable object for more than two of its supposed cycles. The X-ray emission characteristics are appropriate indicators of the difference between a genuine Wolf-Rayet star and a specimen of a super soft source as sometimes suggested in the literature. The X-ray emission analysis might contribute to understanding the origin of the emitting plasma (intrinsically shocked wind, magnetically confined wind, colliding winds, and accretion onto a white dwarf or a more compact object) and to substantiating the decision about the exact nature of the star. <BR /> Methods: The X-ray observations of WR 46 were performed with the XMM-Newton facility over an effective exposure time of about 70 ks. <BR /> Results: Both the X-ray luminosity of WR 46, typical of a Wolf-Rayet star, and the existence of a relatively hard component (including the Fe-K line) rule out the possibility that WR 46 could be classified as a super soft source, and instead favour the Wolf-Rayet hypothesis. The X-ray emission of the star turns out to be variable below 0.5 keV but constant at higher energies. The soft variability is associated to the Wolf-Rayet wind, but revealing its deep origin necessitates additional investigations. It is the first time that such a variability is reported for a Wolf-Rayet star. Indeed, the X-ray emission exhibits a single-wave variation with a typical timescale of 7.9 h which could be related to the period observed in the visible domain both in radial velocities (single-wave) and in photometry (double-wave). The global X-ray emission seems to be dominated by lines and is closely reproduced by a three-temperature, optically thin, thermal plasma model. The derived values are 0.1-0.2 keV, 0.6 keV, and ~4 keV, which indicates that a wide range of temperatures is actually present. The soft emission part could be related to a shocked-wind phenomenon. The hard tail of the spectrum cannot presently be explained by such an intrinsic phenomenon as a shocked wind and instead suggests there is a wind-wind collision zone, as does the relatively high L[SUB]X[/SUB]/L[SUB]bol[/SUB] ratio. We argue that this scenario implies the existence of an object farther away from the WN3 object than any possible companion in an orbit related to the short periodicity. Based on observations with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA). [less ▲]

Detailed reference viewed: 28 (5 ULg)
Full Text
Peer Reviewed
See detailThe multiplicity of O-type stars in NGC 2244
Mahy, Laurent ULg; Rauw, Grégor ULg; Martins, F. et al

in Bulletin de la Societe Royale des Sciences de Liege (2011), 80

The investigation of the multiplicity of massive stars is crucial to determine a robust binary fraction but also for understanding the physical properties of these objects. In this contribution, we will ... [more ▼]

The investigation of the multiplicity of massive stars is crucial to determine a robust binary fraction but also for understanding the physical properties of these objects. In this contribution, we will present the main results from our long-term spectroscopic survey devoted to the young open cluster NGC 2244. We discuss the spectral classification, the projected rotational velocity (v sin{i}) and the multiplicity of O-stars. The stellar and wind parameters of each star, obtained using the CMFGEN atmosphere code, help us to better constrain the individual properties of these objects. Several of these stars were observed by the CoRoT satellite (SRa02) in the Asteroseismology channel. This intensive monitoring and the unprecedented quality of the light curves allow us to shed a new light on these objects. [less ▲]

Detailed reference viewed: 18 (2 ULg)
Full Text
Peer Reviewed
See detailA first orbital solution for the non-thermal radio emitter Cyg OB2 #9
Nazé, Yaël ULg; Damerdji, Yassine ULg; Rauw, Grégor ULg et al

in Bulletin de la Société Royale des Sciences de Liège (2011), 80

We reported in 2008 the first detection of the binary nature of Cyg OB2 #9. Since then, we have continued our spectroscopic monitoring of this object, doubling the number of available spectra of the star ... [more ▼]

We reported in 2008 the first detection of the binary nature of Cyg OB2 #9. Since then, we have continued our spectroscopic monitoring of this object, doubling the number of available spectra of the star while covering a second periastron passage. Using a variety of techniques, the radial velocities were estimated and a first, preliminary orbital solution was derived (P=2.4 yrs). The mass ratio appears close to unity and the eccentricity is large, 0.7-0.75. [less ▲]

Detailed reference viewed: 12 (2 ULg)
Full Text
Peer Reviewed
See detailProspects for the multiplicity investigation of massive stars with the CARLINA interferometer
De Becker, Michaël ULg; Le Coroller, Hervé; Dejonghe, Julien

in Bulletin de la Societe Royale des Sciences de Liege (2011), 80

The multiwavelength study of massive stars has revealed many phenomena that are intimately related to their multiplicity. Colliding winds in massive binaries play indeed a significant role in thermal X ... [more ▼]

The multiwavelength study of massive stars has revealed many phenomena that are intimately related to their multiplicity. Colliding winds in massive binaries play indeed a significant role in thermal X-ray emission, particle acceleration, or even dust formation in such systems. In this context, the identification of binaries and the determination of their orbital parameters is a pivotal issue. We first briefly describe the CARLINA project. The sensitivity and imaging capability of Carlina are perfectly adapted for the study of binary systems. Considering its expected specifications, Carlina will operate in complementarity with ELTs and kilometer baseline interferometers. Then, we discuss some prospects for the multiplicity investigation of massive stars, on the basis of the expected performances of the prototype currently studied at the Observatoire de Haute-Provence (OHP). [less ▲]

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailFirst results on the optical campaign devoted to the gamma-ray binary candidate HD259440
De Becker, Michaël ULg; McSwain, M Virginia; Aragona, Christina

in Bulletin de la Societe Royale des Sciences de Liege (2011), 80

Quite recently, a very high-energy gamma-ray source has been detected in the Monoceros region. This source belongs to the category of TeV emitters with no identified counterpart at other wavelengths, even ... [more ▼]

Quite recently, a very high-energy gamma-ray source has been detected in the Monoceros region. This source belongs to the category of TeV emitters with no identified counterpart at other wavelengths, even though it may be coincident with other high-energy sources detected with other observatories (ROSAT, CGRO). However, it is interesting to note that the error box of this TeV source admits the possibility that the Be star HD259440 is at the origin of the high-energy emission. This may be possible only if that Be star is member of a still undetected binary system including a compact (neutron star or black hole) companion, therefore belonging to the very scarce category of gamma-ray binaries. We describe here the first results of the optical campaign devoted to HD 259440, with emphasis on the investigation of its multiplicity, using spectra obtained at the Observatoire de Haute-Provence (OHP) and at the Kitt Peak National Observatory (KPNO). [less ▲]

Detailed reference viewed: 9 (0 ULg)
Full Text
Peer Reviewed
See detailA Multiwavelength Study of the Runaway Binaries HD 14633 and HD 15137
McSwain, M Virginia; De Becker, Michaël ULg; Roberts, Mallory S E et al

in Bulletin de la Societe Royale des Sciences de Liege (2011), 80

The runaway O-type binaries HD 14633 and HD 15137 were likely ejected from the cluster of their birth by supernovae explosions in close binaries. Here we present recent optical spectra to update the ... [more ▼]

The runaway O-type binaries HD 14633 and HD 15137 were likely ejected from the cluster of their birth by supernovae explosions in close binaries. Here we present recent optical spectra to update the orbital solutions of the binaries and study the physical parameters of the O star primaries. We also present XMM-Newton observations of both systems that attempt to detect hard power-law emission from compact companions. EPIC spectra of HD 14633 at periastron and apastron reveal a non-thermal X-ray flux component that is variable during the orbit. Our EPIC spectra of HD 15137 indicate thermal X-ray emission consistent with an isolated O star. We provide an upper limit on the emission from a compact companion in HD 15137. [less ▲]

Detailed reference viewed: 11 (0 ULg)