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1.
The radial velocities of the star BM Ori are determined from spectra obtained by the HST and IUE satellites, as well as from spectra obtained with the BTA telescope. An analysis of this data shows that the radial velocities of the main star and its satellite experience an irregular positive shift by 20-30 km/s. This fact can only be interpreted in terms of the presence of yet another star in the binary system. The new observations have made it possible to significantly improve the accuracy of the spectroscopic elements of the orbit of the close binary system and to estimate the orbital characteristics of the third body. The preliminary values of the elements are: Ep=JD2444744, P=1302d, =11km/s, e=0.92, K=20km/s, and =1.6rad.  相似文献   

2.
We report the physical and orbital parameters of the visible component of the spectroscopic binary HD37737 (m V = 8.03). The observations were performed with the 1.2-m telescope of the Kourovka Astronomical Observatory of the Ural Federal University in 2012 and the 6-m BTA telescope of the SAO RAS in 2007 and 2009. Radial velocities were measured separately from each spectral line of the list by the cross-correlation method with a synthetic spectrum. The latter was calculated using the grids of non-LTE model atmospheres with solar chemical compositions. A significant difference in the epochs of observations (2005–2012) allowed to refine the orbital period of the star (7 · d 84705) and the orbital elements of the binary system. We obtained an estimate of the mass function f(m) = 0.23 ± 0.02M ⊙. The best agreement between the synthetic and observed spectra is achieved at T eff = 30 000 K and log g = 3.50 according to the observations on both instruments. The obtained parameters correspond to a star of spectral type O9.5 III, with mass estimated at 26 ± 2M ⊙. The minimum mass estimate of the secondary component of the binary is 6.2 ± 0.5M ⊙. We have discovered a fact that the velocities, obtained from different spectral lines, differ, which is typical for giant stars. Engaging additional spectra, obtained in 2005 with the 2.1-m KPNO telescope, we investigated the effect of this fact on the estimate of the speed of the system’s center of mass. The difference in the velocities of various lines is approximately the same in the spectra, obtained at all the three instruments. The obtained ratios suggest that the deeper layers of the atmosphere of the star are moving with a greater velocity than the outer layers. Depending on the line, the estimate of the heliocentric velocity of the binary’s center of mass varies in the range from ?11 to 1 km/s.  相似文献   

3.
The radial velocities of the Ap star 53 Cam = HD 65339 show a longtime variation corresponding to a binary motion. For the elements of the binary system the following values were derived: K = 8km/s, γ = -2.2 km/s, P = 2380 days. e = 0.56, ω = 10°, and a · sin i = 22 · 107 km. A second period of about 1850 days is indicated but this value seems to be a spurious period. Investigations of ZEEMAN spectrograms made by several authors gave a magnetic period of a bout 8 days. This period, interpreted as rotational period of the star, obviously differs a little for various observational times depending on the position in the binary orbit; so that the period is smaller at the time of the apastron passage. At present it is not possible to decide wheter this behaviour – if real – preponderantly reflects changes of the velocity of rotation or of the magnetic field. Furthermore the radial velocities show a dependence on the state of ionization of the elements in such a way that evidently lines from neutral elements have larger radial velocities (absolute values) than those of the ionized elements. These differences also depend on the position in the binary orbit as mentioned for the magnetic periods.  相似文献   

4.
We present new radial velocities of the high‐mass X‐ray binary star 4U 2206+54 based on optical spectra obtained with the Coudé spectrograph at the 2 m RCC telescope of the Rozhen National Astronomical Observatory, Bulgaria in the period November 2011–July 2013. The radial velocity curve of the He I δ6678 Å line is modeled with an orbital period Porb = 9.568 d and an eccentricity of e = 0.3. These new measurements of the radial velocity resolve the disagreements of the orbital period discussions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

5.
The results of radial velocity measures of the star o And from high dispersion plates relative to the years 1964, 1966, 1975 and 1976 are given. The averaged values of the 1964 and 1966 plates confirm the existence of the minimum in the trend of the radial velocities and fit well the curve obtained in the hypothesis of periodic long-term radial velocity variations with the period of 23.5 years (Fracassiniet al., 1977). Preliminary orbital elements in the hypothesis of a long period spectroscopic binary system have been tentatively drawn.  相似文献   

6.
From two sets of the spectroscopic observations covering a ten year period we have obtained 59 radial velocities of the chromospherically-active star HD 28591 = V492 Per. It is a G9III single-lined spectroscopic binary with a period of 21.2910 days and a circular orbit. Thev sini of 24.6 km s–1, results in a minimum radius 10.3R . We estimate a distance of 165 ± 40 pc and an orbital inclination of 65 ± 25 degrees. The secondary is probably a mid to late-type K dwarf. The star is brighter than the limiting magnitude of theBright Star Catalogue. The mean photometric and the orbital periods are identical within their uncertainties. Since the star fills a significant fraction of its Roche lobe, about 62%, the photometric light curve may be the result of starspots and a modest ellipticity effect.Visiting astronomer, Kitt Peak National Observatory, NOAO, operated by AURA, Inc., under contract with the NSF  相似文献   

7.
This paper is the first of a series on radial velocities measures of the chromospherically-active and suspected stars. The chromospherically-active star BD + 25°2511 = HZ Com is found to be double-lined spectroscopic binary with an orbital period of3.558317 days and an eccentricity of0.013 ± 0.006. The orbital period does not differ substantially from the previously determined photometric period. If the photometric period is correct, this system is rotating synchronously and imposes important constraints on theories of synchronization and circularization of binary systems.  相似文献   

8.
Using a sample of 315 observations we have camputed the definitive orbital elements of the visual binary star ADS 5871 — STF 1037. The provisional elements obtained by KOWALSKY's method have been corrected with the differential method of HELLERICH . At last we have calculated the dynamical parallax of the system and its total mass.  相似文献   

9.
High-speed spectroscopy of two pulsating subdwarf B stars, KPD 2109+4401 and PB 8783, is presented. Radial motions are detected with the same frequencies as reported from photometric observations and with amplitudes of ∼2 km s−1 in two or more independent modes. These represent the first direct observations of surface motion arising from multimode non-radial oscillations in subdwarf B stars. In the case of the sdB+F binary PB 8783, the velocities of both components are resolved; high-frequency oscillations are found only in the sdB star and not the F star. There also appears to be evidence for mutual motion of the binary components. If confirmed, it implies that the F-type companion is ≳1.2 times more massive than the sdB star, while the amplitude of the F-star acceleration over 4 h would constrain the orbital period to lie between 0.5 and 3.2 d.  相似文献   

10.
From radial velocities determined in high signal-to-noise digital spectra, we report the discovery that the brightest component of the binary system HD 150136 is of spectral type O3. We also present the first double-lined orbital solution for this binary. Our radial velocities confirm the previously published spectroscopic orbital period of 2.6 d. He  ii absorptions appear double at quadratures, but single lines of N  v and N  iv visible in our spectra define a radial velocity orbit of higher semi-amplitude for the primary component than do the He  ii lines. From our orbital analysis, we obtain minimum masses for the binary components of 27 and  18 M⊙  . The neutral He absorptions apparently do not follow the orbital motion of any of the binary components, thus they most probably arise in a third star in the system.  相似文献   

11.
The Behlen observatory 0.76 m telescope CCD photometer is used to obtain 347 observations of the short period (P0d.4) eclipsing binary star V719 Her. The observations done withV andR bandpass filters were made on 6 nights in 1993. Previously published light elements and the present five timings of minimum provide a new epoch and a more accurate orbital period of 0.4009828 days. Our analyses show that the period of the system appears to decrease. We recommend future monitoring of the eclipse minima for this system. No published spectral classification for V719 Her exists. From the color,V-R=0.391, we estimate it to be about F5.The 1993 version of the Wilson Devinney model gave the photometric solutions. The adopted solution indicates that V719 Her is a W UMa type contact binary. The mass ratio,q=(m 2/m 1, where star 1 eclipse at the primary minimum)=0.296 suggests that V719 Her is a WUMa system with type-A (transit during primary eclipse) configuration. The secondary minimum shows a total eclipse. V719 Her with period less than 0.5 and spectral class F5, is probably a zero-age contact system. Since our photometric solution shows that the luminosity difference between the components is very large, we suspect that V719 Her is most likely a single line spectroscopic binary. We recommend spectroscopic study of this system.  相似文献   

12.
Analysis of the radial velocities based on spectra of high (near the H α line) and moderate (4420–4960 Å) resolutions supplemented by the published radial velocities has revealed the binarity of a bright member of the young open star cluster χ Per, the star V622 Per. The derived orbital elements of the binary show that the lines of both components are seen in its spectrum, the orbital period is 5.2 days, and the binary is in the phase of active mass exchange. The photometric variability of the star is caused by the ellipsoidal shape of its components. Analysis of the spectroscopic and photometric variabilities has allowed the absolute parameters of the binary’s orbit and its components to be found. V622 Per is shown to be a classical Algol with moderate mass exchange in the binary. Mass transfer occurs from the less massive (\({M_1} = 9.1 \pm 2.7{M_ \odot }\)) but brighter (\(\log {L_1} = 4.52 \pm 0.10{L_ \odot }\)) component onto the more massive (\({M_2} = 13.0 \pm 3.5{M_ \odot }\)) and less bright (\(\log {L_2} = 3.96 \pm 0.10{L_ \odot }\)) component. Analysis of the spectra has confirmed an appreciable overabundance of CNO-cycle products in the atmosphere of the primary component. Comparison of the positions of the binary’s components on the T eff–log g diagram with the age of the cluster χ Per points to a possible delay in the evolution of the primary component due to mass loss by no more than 1–2Myr.  相似文献   

13.
The orbital elements of the binary star ADS 9979 – σCRB were determined with the method of KOWALSKY , by the use of 886 observations. These provisional elements were then corrected with the differential method of HELLERICH . At last the total mass of the system was calculated and the dynamical parallax was obtained with the method of BAIZE –ROMANI .  相似文献   

14.
New UBV-photoelectric observations of the well-known massive X-ray binary system Cyg X-1/V 1357 Cyg are obtained near the primary minimum. The detailed analysis of these observations confirms the existence of additional blue radiation which appears as a narrow peak with an amplitude of 0.01–0.02 mag near phase 0.00 on the light curve (the superior conjunction of the relativistic component), firstly detected by Lyuty (1985). This emission does not appear at every orbital cycle. The appearance of this narrow peak of additional blue radiation on the light curve of Cyg X-1 can be explained as the radiation of relativistic electrons in the disturbed magnetic field of the optical star in frames of the model proposed by Ikhsanov and Fabrika (1990).  相似文献   

15.
Using a sample of 602 observations we have recomputed the orbital elements of the visual binary star ADS 10 345–m̈Dra. The provisional elements obtained by KOWALSKY METHOD HAVE BEEN CORRECTED WITH THE DIFFERENTIAL METHOD OF HELLERICH . At last we have calculated the dynamical parallax of the system and its total mass.  相似文献   

16.
We report on observations of the eclipsing binary 2MASS 19090585+4911585 with the 25 cm auxiliary telescope of the University Observatory Jena. We show that a nearby brighter star (2MASS 19090783+4912085) was previously misclassified as the eclipsing binary and find 2MASS 19090585+4911585 to be the true source of variation. We present photometric analysis of VRI light curves. The system is an overcontact binary of W UMa type with an orbital period of (0.288374 ± 0.000010) d (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
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         . The identification of the components as WO4+O5((f)) indicates a massive evolved binary system; the O5 component is a main-sequence or, more likely, a giant star. The radial velocities of the O star yield a circular orbit with an amplitude         and a mass function of 0.013     . The spectrum of WR 30a exhibits strong profile variations of the broad emission lines that are phase-locked with the orbital period. We report the detection of the orbital motion of the WO component with     , but this should be confirmed by further observations. If correct, it implies a mass ratio     . The star exhibits sinusoidal light variations of amplitude 0.024 mag peak-to-peak with the minimum of light occurring slightly after the conjunction with the O star in front. On the basis of the phase-locked profile variations of the C  iv λ 4658 blend in the spectrum of the WO, we conclude that a wind–wind collision phenomenon is present in the system. We discuss some possibilities for the geometry of the interaction region.  相似文献   

18.
We use the method introduced by Karami & Mohebi (2007), and Karami & Teimoorinia (2007) which enable us to derive the orbital parameters of the spectroscopic binary stars by the nonlinear least squares of observed vs. curve fitting (o-c). Using the measured experimental data for radial velocities of the four double-lined spectroscopic binary systems PV Pup, HD 141929, EE Cet and V921 Her, we find both the orbital and the combined spectroscopic elements of these systems. Our numerical results are in good agreement with those obtained using the method of Lehmann-Filhés.  相似文献   

19.
The results of speckle interferometric observations of 104 binary and 6 triple stars performed at the BTA 6 m telescope in 2004 October are presented. Nearby low-mass stars are mostly observed for the program, among which 59 there are new binaries recently discovered by the Hipparcos astrometric satellite. Concurrently with the diffraction-limited position measurements we obtained 154 brightness ratio measurements of binary and multiple star components in different bands of the visible spectrum. New, first-resolved binaries are the symbiotic star CH Cyg with a weak companion at 0.043″ separation and the pair of red dwarfs, GJ 913 = HIP 118212. In addition, we derived the orbital parameters for two interferometric systems: the CN-giant pair HD 210211 = HIP 109281 (P = 10.7 yr) and the G2V-K2V G2V-K2V binary GJ 9830 = HIP 116259 (P = 15.7 yr).  相似文献   

20.
The RS CVn-type eclipsing binary star MM Her has been observed in two colours,B andV, in 1979, 1980, and 1983. Several minima times were obtained during the observations and new light elements calculated. The light curves of the system obtained in blue and yellow lights show a significant wave-like distortion which migrates towards the decreasing orbital phases. Its migration period was estimated to be about 3.5 yr. The amplitudes of the wave-like distortion inB andV appear to change each year. The primary minimum of the system is a total eclipse with a duration of 0d.08.  相似文献   

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