scholarly journals Dependence of the absorption-line profiles and radial-velocity curve of the optical star in an X-ray binary on the orbital inclination and component-mass ratio

2005 ◽  
Vol 49 (10) ◽  
pp. 801-813 ◽  
Author(s):  
M. K. Abubekerov ◽  
É. A. Antokhina ◽  
A. M. Cherepashchuk
Keyword(s):  
Radial Velocity ◽  
Absorption Line ◽  
Velocity Curve ◽  
Line Profiles ◽  
Mass Ratio ◽  
Radial Velocity Curve ◽  
Orbital Inclination ◽  
X Ray ◽  
Optical Star

scholarly journals The supergiant O + O binary system HD 166734: a new study

2016 ◽  
Vol 12 (S329) ◽  
pp. 402-402 ◽  
Author(s):  
E. Gosset ◽  
L. Mahy ◽  
Y. Damerdji ◽  
C. Nitschelm ◽  
H. Sana ◽  
...  
Keyword(s):  
Binary System ◽  
Light Curve ◽  
Radial Velocity ◽  
Velocity Curve ◽  
Physical Parameters ◽  
Radial Velocity Curve ◽  
X Ray ◽  
Orbital Parameters

AbstractWe present here a modern study of the radial velocity curve and of the photometric light curve of the very interesting supergiant O7.5If + O9I(f) binary system HD 166734. The physical parameters of the stars and the orbital parameters are carefully determined. We also perform the analysis of the observed X-ray light curve of this colliding-wind binary.

scholarly journals Asymmetry of metallic spectral lines in Cepheids

1993 ◽  
Vol 139 ◽  
pp. 375-375
Author(s):  
Michael Albrow ◽  
P.L. Cottrel
Keyword(s):  
High Resolution ◽  
Radial Velocity ◽  
Velocity Curve ◽  
Radial Velocities ◽  
Spectral Lines ◽  
Line Profiles ◽  
Radial Velocity Curve ◽  
Spectroscopic Observations ◽  
The Asymmetry

AbstractA program of high resolution spectroscopic observations of Cepheids has been carried out at Mt John University Observatory for several years. Radial velocities and asymmetries have been measured for selected metallic lines using the method of Wallerstein et al (1992).The line profiles show the largest asymmetry at phases of maximum inward velocity. The asymmetry at phases of maximum outward velocity is smaller and sometimes in the same direction as for the inward velocity maxima. Enhanced asymmetry is also noticed at phases where the bump appears on the radial velocity curve.To date our models are unable to predict such behaviour. It is important that a satisfactory explaination for these observations be found so that the accuracy of Baade-Wesselink radius solutions for such stars can be assessed.

scholarly journals The Radial Velocity Curve of V652 Her (BD+13°3224)

1985 ◽  
Vol 87 ◽  
pp. 109-115
Author(s):  
P.W. Hill ◽  
C.S. Jeffery
Keyword(s):  
Radial Velocity ◽  
Time Resolution ◽  
High Frequency ◽  
Velocity Curve ◽  
Velocity Data ◽  
Effective Surface ◽  
Radial Velocity Curve ◽  
Minimum Radius ◽  
Helium Star ◽  
Radial Velocity Data

AbstractNew radial velocity data for the pulsating extreme helium star V652 Her (BD+13°3224) have been obtained with a time resolution of 100 s. High frequency structure in the radial velocity curve is detected, and a comparison with previous data suggests that the detailed shape of the velocity curve is variable. The data imply that the effective surface gravity must increase by a factor of 4 at minimum radius.

The radial-velocity curve of V1010 Ophiuchi - Orbital elements and the rotational disturbance

1988 ◽  
Vol 100 ◽  
pp. 371 ◽  
Author(s):  
Thaddeus F. Worek ◽  
Eugene R. Zizka ◽  
Merle W. King ◽  
Joost H. Kiewiet de Jonge
Keyword(s):  
Radial Velocity ◽  
Velocity Curve ◽  
Orbital Elements ◽  
Radial Velocity Curve

scholarly journals Observations of Highly-Ionized Interstellar Iron

1984 ◽  
Vol 81 ◽  
pp. 189-191
Author(s):  
L.M. Hobbs
Keyword(s):  
Radial Velocity ◽  
Absorption Line ◽  
Equivalent Width ◽  
Column Density ◽  
Light Path ◽  
Interstellar Gas ◽  
X Ray ◽  
X Ray Background ◽  
Multi Phase ◽  
No Absorption

AbstractThe spectra of 24 stars, including 5 at distances d < 200 pc, have been observed in the regions of the coronal [Fe X] λ6375 and [Fe XIV] λ5303 lines at detection limits near an equivalent width of 1 mÅ in the best cases. In general agreement with predictions based on a multi-phase model of the interstellar medium, no absorption which can be attributed to Fe X or Fe XIV ions in hot interstellar gas emitting the soft x-ray background is seen in any of these spectra, except for two. Toward λ Cephei an absorption line near λ6375 is measured with an equivalent width of 8.1 ± 2 mÅ, a width corresponding to 20 ± 5 km s-1 or a temperature T ≤ (0.5 ± 0.25) x 106 °K, and, if it is caused by Fe X ions, a radial velocity of -355 km s-1. On that hypothesis, the hot interstellar gas constitutes at least 63% of the column density of gas along this light path.

scholarly journals Evidence for a Black Hole in LMC X-3

1984 ◽  
Vol 108 ◽  
pp. 241-242
Author(s):  
A. P. Cowley ◽  
D. Crampton ◽  
J. B. Hutchings ◽  
R. Remillard
Keyword(s):  
Black Hole ◽  
Mass Function ◽  
Orbital Elements ◽  
Orbital Inclination ◽  
X Ray ◽  
Average Mass ◽  
Early Type Star ◽  
Optical Star ◽  
Modulation Collimator ◽  
Einstein Observatory

The best X-ray position (Einstein Observatory HRI - Giacconi et al 1979) for LMC X-3 confirms its identification with the early type star first suggested by Warren and Penfold (1975). Our spectroscopic observations obtained with the CTIO 4–m telescope show the WP star is a slightly reddened B3 V star with mV ≈ 16.9. Large radial velocity variations (Δv ≈ 500 km s−1) reveal an orbital period of 1.7049 days. From the orbital elements (Table 1) one can determine the mass function f(M) = (Mx sin i)3/(Mopt + Mx)2 = 2.3 M⊙, which shows without any assumptions about the mass of the optical star, the orbital inclination, or the mass ratio the unseen X-ray object has a mass >2.3 M⊙. Detailed analysis of the HEAO–1 scanning modulation collimator X-ray data shows that the system does not eclipse, implying that the orbital inclination is ≤ 65°. Assuming the B star mass lies between 4 and 8 M⊙ (an average mass for a normal B3 V star would be about 6–7 M⊙), the mass of the unseen companion must lie between 7 and 13 M⊙ (see Fig. 4a - Hutchings, this volume). Smaller inclinations of course give even higher masses. An important point is that the unseen star must have a mass larger than that of the B star, and thus if it were any kind of normal star it should be easily seen in the spectrum. Thus the X-ray emitting object is a very good candidate for a black hole.

scholarly journals A new radial velocity curve for the RS CVn star σ Gem

1997 ◽  
Vol 123 (2) ◽  
pp. 209-218 ◽  
Author(s):  
R. Duemmler ◽  
I. V. Ilyin ◽  
I. Tuominen
Keyword(s):  
Radial Velocity ◽  
Velocity Curve ◽  
Radial Velocity Curve
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