A 2.3-Day Periodic Variability in the Apparently Single Wolf-Rayet Star WR 134: Collapsed Companion or Rotational Modulation?

We present the results of an intensive campaign of spectroscopic and photometric monitoring of the peculiar Wolf-Rayet star WR 134 from 1989 to 1997. This unprecedentedly large data set allows us to confirm unambiguously the existence of a coherent 2.25 +/- 0.05 day periodicity in the line-profile changes of He II 4686, although the global pattern of variability is different from one epoch to another. This period is only marginally detected in the photometric data set. Assuming the 2.25 day periodic variability to be induced by orbital motion of a collapsed companion, we develop a simple model aiming at investigating (i) the effect of this strongly ionizing, accreting companion on the Wolf-Rayet wind structure, and (ii) the expected emergent X-ray luminosity. We argue that the predicted and observed X-ray fluxes can only be matched if the accretion on the collapsed star is significantly inhibited. Additionally, we performed simulations of line-profile variations caused by the orbital revolution of a localized, strongly ionized wind cavity surrounding the X-ray source. A reasonable fit is achieved between the observed and modeled phase-dependent line profiles of He II 4686. However, the derived size of the photoionized zone substantially exceeds our expectations, given the observed low-level X-ray flux. Alternatively, we explore rotational modulation of a persistent, largely anisotropic outflow as the origin of the observed cyclical variability. Although qualitative, this hypothesis leads to greater consistency with the observations.Comment: 34 pages, 16 figures. Accepted by the Astrophysical Journa

Optical Spectroscopy of X-Mega targets in Carina Nebula : III. The multiple system Tr 16-104 (≡CPD -59° 2603)

We discuss the orbital elements of the multiple system Tr 16-104 which is usually believed to be a member of the open cluster Trumpler 16 in the Carina complex. We show that Tr 16-104 could be a hierarchical triple system consisting of a short-period (2.15 d) eclipsing O7 V+O9.5 V binary bound to a B0.2 IV star. Our preliminary orbital solution of the third body indicates that the B star most probably describes an eccentric orbit with a period of ∼285 or ∼1341 d around the close binary. Folding photometric data from the literature with our new ephemerides, we find that the light curve of the close binary exhibits rather narrow eclipses indicating that the two O stars must be well inside their Roche lobes. Our analysis of the photometric data yields a lower limit on the inclination of the orbit of the close binary of i≥77°. The stellar radii and luminosities of the O7 V and O9.5 V stars are significantly smaller than expected for stars of this spectral type. Our results suggest that Tr 16-104 lies at a distance of the order of 2.5 kpc and support a fainter absolute magnitude for zero-age main-sequence O stars than usually adopted. We find that the dynamical configuration of Tr 16-104 corresponds to a hierarchical system that should remain stable provided that it suffers no strong perturbation. Finally, we also report long-term temporal variations of high-velocity interstellar Ca ii absorptions in the line of sight towards Tr 16-104.Facultad de Ciencias Astronómicas y Geofísica

Optical Spectroscopy of X-Mega targets in Carina Nebula : III. The multiple system Tr 16-104 (≡CPD -59° 2603)

We discuss the orbital elements of the multiple system Tr 16-104 which is usually believed to be a member of the open cluster Trumpler 16 in the Carina complex. We show that Tr 16-104 could be a hierarchical triple system consisting of a short-period (2.15 d) eclipsing O7 V+O9.5 V binary bound to a B0.2 IV star. Our preliminary orbital solution of the third body indicates that the B star most probably describes an eccentric orbit with a period of ∼285 or ∼1341 d around the close binary. Folding photometric data from the literature with our new ephemerides, we find that the light curve of the close binary exhibits rather narrow eclipses indicating that the two O stars must be well inside their Roche lobes. Our analysis of the photometric data yields a lower limit on the inclination of the orbit of the close binary of i≥77°. The stellar radii and luminosities of the O7 V and O9.5 V stars are significantly smaller than expected for stars of this spectral type. Our results suggest that Tr 16-104 lies at a distance of the order of 2.5 kpc and support a fainter absolute magnitude for zero-age main-sequence O stars than usually adopted. We find that the dynamical configuration of Tr 16-104 corresponds to a hierarchical system that should remain stable provided that it suffers no strong perturbation. Finally, we also report long-term temporal variations of high-velocity interstellar Ca ii absorptions in the line of sight towards Tr 16-104.Facultad de Ciencias Astronómicas y Geofísica

Towards an understanding of the Of?p star HD 191612: optical spectroscopy

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 well-determined 538-d period. Metal lines and HeII absorptions (including many selective emission lines but excluding He II 4686A emission) are essentially constant in line strength, but are variable in velocity, establishing a double-lined binary orbit with P(orb) = 1542d, e=0.45. We conduct a model-atmosphere analysis of the primary, and find that the system is consistent with a O8: giant with a B1: main-sequence secondary. Since the periodic 538-d changes are unrelated to orbital motion, rotational modulation of a magnetically constrained plasma is strongly favoured as the most likely underlying `clock'. An upper limit on the equatorial rotation is consistent with this hypothesis, but is too weak to provide a strong constraint.Comment: Accepted for MNRA

XMM-Newton X-ray study of early type stars in the Carina OB1 association

<p><b>Aims:</b> 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 nature of X-ray formation mechanisms in the winds of single and binary early-type stars.</p> <p><b>Methods:</b> A timing and spectral analysis of five observations with XMM-Newton is performed using various statistical tests and thermal spectral models.</p> <p><b>Results:</b> 235 point sources have been detected within the field of view. Several of these sources are probably pre-main sequence stars with characteristic short-term variability. Seven sources are possible background AGNs. Spectral analysis of twenty four sources of type OB and WR 25 was performed. We derived spectral parameters of the sources and their fluxes in three energy bands. Estimating the interstellar absorption for every source and the distance to the nebula, we derived X-ray luminosities of these stars and compared them to their bolometric luminosities. We discuss possible reasons for the fact that, on average, the observed X-ray properties of binary and single early type stars are not very different, and give several possible explanations.</p&gt

A phase-resolved XMM-Newton Campaign on the Colliding Wind Binary HD 152248

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, which is the brightest X-ray source of the cluster. The campaign, with a total duration of 180 ksec, was split into six separate observations, following the orbital motion of HD 152248. The X-ray flux from this system presents a clear, asymmetric modulation with the phase and ranges from 0.73 to 1.18 10-12 erg s-1 cm-2 in the [0.5-10.0 keV] energy band. The maximum of the emission is reached slightly after apastron. The EPIC spectra are quite soft and peak around 0.8-0.9 keV. We characterize their shape using several combinations of mekal models and power-law spectra and we detect significant spectral variability in the [0.5-2.5 keV] energy band. We also perform 2-D hydrodynamical simulations using different sets of parameters that closely reproduce the physical and orbital configuration of the HD 152248 system at the time of the six XMM-Newton pointings. This allows a direct confrontation of the model predictions with the constraints deduced from the X-ray observations of the system. We show that the observed variation of the flux can be explained by a variation of the X-ray emission from the colliding wind zone, diluted by the softer X-ray contribution of the two O-type stars of the system. Our simulations also reveal that the interaction region of HD 152248 should be highly unstable, giving rise to shells of dense gas that are separated by low density regions. Finally, we perform a search for short-term variability in the light curves of the system and we show that trends are present within several of the 30 ksec exposures of our campaign. Further, most of these trends are in good .Comment: Accepted by MNRAS; 22 pages; without figures; complete PS version (including figures) on http://vela.astro.ulg.ac.be/Preprints/index.htm

Electron Cooling Experiments in CSR

The six species heavy ion beam was accumulated with the help of electron cooling in the main ring of Cooler Storage Ring of Heavy Ion Research Facility in Lanzhou(HIRFL-CSR), the ion beam accumulation dependence on the parameters of cooler was investigated experimentally. The 400MeV/u 12C6+ and 200MeV/u 129Xe54+ was stored and cooled in the experimental ring CSRe, the cooling force was measured in different condition.Comment: 5 pages 11 figure

Age and gender peculiarities of hysterical neurotic psychopathology

The purpose of research was definition of psychopathological peculiarities of hysterical neurotic disorders and to reveal influence of age and gender factors. We investigated 109 patients. There were 62 patients in the basic group (23 of them were men and 39 of them were women) at the age from 45 to 63 and 47 patient in the control group (19 of them were men and 28 were women) at the age from 18 to 44. It is established that old age is characterized in anxious depression with egocentric orientation, shocking blackmailing destructive aggressive infantile behavior, substantial dimorphism of conversion displays, somatophorms disorders of women and obsessive compulsive disorders of men.Цель работы: с целью определения психопатологических особенностей истерических невротических расстройств у больных с учётом патоформирующего влияния возрастного и гендерного факторов обследовано 109 пациентов: 62 пациента (23 мужчины и 39 женщин) в возрасте от 45 до 63 лет составили основную группу, 47 пациентов (19 мужчин и 28 женщин) в возрасте от 18 до 44 лет - контрольную. Установлено, что истерическому неврозу в позднем возрасте свойственна тревожная депрессия с эгоцентрической направленностью, эпатажно-шантажным деструктивно-агрессивным инфантильным поведением, содержательным диморфизмом конверсионных проявлений, соматоформными расстройствами у женщин и обсессивно-компульсивными расстройствами - у мужчин