7,090 research outputs found

    Strongly absorbed quiescent X-ray emission from the X-ray transient XTE J0421+56 (CI Cam) observed with XMM-Newton

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    We have observed the X-ray transient XTE J0421+56 in quiescence with XMM-Newton. The observed spectrum is highly unusual being dominated by an emission feature at ~6.5 keV. The spectrum can be fit using a partially covered power-law and Gaussian line model, in which the emission is almost completely covered (covering fraction of 0.98_{-0.06}^{+0.02}) by neutral material and is strongly absorbed with an N_H of (5_{-2}^{+3}) x 10^{23} atom cm^{-2}. This absorption is local and not interstellar. The Gaussian has a centroid energy of 6.4 +/- 0.1 keV, a width < 0.28 keV and an equivalent width of 940 ^{+650}_{-460} eV. It can be interpreted as fluorescent emission line from iron. Using this model and assuming XTE J0421+56 is at a distance of 5 kpc, its 0.5-10 keV luminosity is 3.5 x 10^{33} erg s^{-1}. The Optical Monitor onboard XMM-Newton indicates a V magnitude of 11.86 +/- 0.03. The spectra of X-ray transients in quiescence are normally modeled using advection dominated accretion flows, power-laws, or by the thermal emission from a neutron star surface. The strongly locally absorbed X-ray emission from XTE J0421+56 is therefore highly unusual and could result from the compact object being embedded within a dense circumstellar wind emitted from the supergiant B[e] companion star. The uncovered and unabsorbed component observed below 5 keV could be due either to X-ray emission from the supergiant B[e] star itself, or to the scattering of high-energy X-ray photons in a wind or ionized corona, such as observed in some low-mass X-ray binary systems.Comment: 8 pages, 4 postscript figures, accepted for publication in Astronomy and Astrophysic

    A BeppoSAX observation of the super-soft source CAL87

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    We report on a BeppoSAX Concentrator Spectrometer observation of the super-soft source (SSS) CAL87. The X-ray emission in SSS is believed to arise from nuclear burning of accreted material on the surface of a white dwarf (WD). An absorbed blackbody spectral model gives a chi^2_v of 1.18 and a temperature of 42 +/- ^13 _11 eV. However, the derived luminosity and radius are greater than the Eddington limit and radius of a WD. Including an O viii edge at 0.871 keV gives a significantly better fit (at > 95% confidence) and results in more realistic values of the source luminosity and radius. We also fit WD atmosphere models to the CAL87 spectrum. These also give reasonable bolometric luminosities and radii in the ranges 2.7-4.8 10^{36} erg/s and 8-20 10^7 cm, respectively. These results support the view that the X-ray emission from CAL87 results from nuclear burning in the atmosphere of a WD.Comment: 4 pages. Accepted for publication in A&A (Letters

    A Comparative Study of Psychological Factor Among Female Athletes

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    Psychological needs play an important role in the promotion and demotion of tension, because any type of tension provide frustration and these frustrated needs leads towards aggressiveness in the individual, need of direct gain, power, and prestige, need for resolving ambiguous cries and for group belongingness and conformity are the main needs which appear to be of utmost importance. The most of the tensions are due to physical, social, cultural, religious, economic, political and psychological cause, and the stability of the tension has been found to be due to high competition, lack of common goals, lack of contacts, value conflict, ignorance, partiality, prejudices, conformity, and maladjustment and to achieve dominance by someone. The objective of this paper is to study to measure different kinds of tension viz. communal tension, caste tension, and religious tension cultural tension regional tension and language tension. For this purpose Fifty female athletes of age group 18-25 participated in south-west zone inter-varsity tournament of respective sport viz judo, badminton; table tennis, wrestling, swimming, and athletics, during 2007-2008 were selected as subjects for this study at random. COMPREHENSIVE SCALE OF TENSION by Dr. Rajeevlochan Bhardwaj was used. Reliability—IT POSSESS SPILT-HALF RELIABILITY OF .81 THROUGH Spearman Brown Formula and of .88 by Gutman Formula. The reliability of data was ensured through tools reliability as well as tester\u27s reliability. The information gathered was treated with ANOVA&nbsp; (F-Ratio) technique was used for comparing all the six sports with respect to Locus of control\u27s-Score- All the scores of comprehensive tension scale are converted to T-Score to find out the level of tension in each of six sports and also in total. It is found from The findings that the study indicates that there is no significant difference among female players of Athletics, Weight Lifting, Judo, Badminton, Swimming and Table Tennis.&nbsp;&nbsp
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