- ID:
- ivo://CDS.VizieR/J/AJ/149/110
- Title:
- Radial velocities of 47 Oph
- Short Name:
- J/AJ/149/110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Although 47 Oph has been shown to be a binary with a period of ~27days using both spectroscopic and interferometric techniques, only a preliminary orbit has been obtained in the previous work due to the shortage of high precision measurements. Since 1997, new spectroscopic and interferometric measurements have been obtained with much higher precision by the spectrograph of the 2.16m telescope at Xinglong station and the Navy Precision Optical Interferometer, respectively. Combining all of the measurements, a three-dimensional orbit is obtained with high precision in this work. Thus, the component masses are calculated to be 1.50+/-0.06 and 1.34+/-0.06M_{sun}_, respectively. The orbital parallax is 32.6+/-0.6mas, which is consistent with the Hipparcos parallax. With the known apparent magnitudes and color indices of the components, the derived luminosities are 7.80+/-0.36 and 3.41+/-0.25L_{sun}_. The estimated radii of the components are 2.06+/-0.07 and 1.36+/-0.06R_{sun}_. Finally, the evolutionary status of the components are investigated with the help of a stellar evolution model.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/502/937
- Title:
- Radial velocities of 9 O-type stars
- Short Name:
- J/A+A/502/937
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results obtained from a long-term spectroscopic campaign to study the multiplicity of O-type stars in both the young open cluster NGC 2244 and the Mon OB2 association. Our spectroscopic monitoring was performed over several years, allowing us to investigate different timescales. For each star, several spectral diagnostic tools were applied to search for line shifts and profile variations. We also measured the projected rotational velocity and revisited the spectral classification.
- ID:
- ivo://CDS.VizieR/J/A+A/354/881
- Title:
- Radial velocities of Praesepe & Hyades Am stars
- Short Name:
- J/A+A/354/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CORAVEL radial-velocity observations of Am stars in the Hyades and Praesepe have allowed the determination of orbital elements for 10 spectroscopic binaries, among which 3 are first determinations. One Am star (KW 40) is found to be a well hierarchised triple system. KW 538 has a rather long period (435 days) for an Am star. Orbits of systems with periods shorter than 8.5 days are circularized, or present eccentricities smaller than 0.04. For 19 Am stars, the number of quadruple-, triple-, double-, single systems is 1:2:14(10+4?):(2?). The Am stars in a ({beta}, B-V) diagram clearly stand away by 0.03mag from the sequence defined by normal main-sequence stars. This diagram could be a powerful method to identify Am stars in more distant open clusters, provided there is no differential reddening. In the colour-magnitude diagram (M_V_, {beta}), double-lined binaries are 0.6-0.7mag above the ZAMS as expected, while most single-lined are close to or on the ZAMS because the secondary does not contribute much light. The absence of X-ray detection of 4 systems in the Hyades is an argument for the presence of a white dwarf secondary.
- ID:
- ivo://CDS.VizieR/J/A+A/490/737
- Title:
- Radial velocities of 3 RasTyc new triple system
- Short Name:
- J/A+A/490/737
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During the study of a large set of late-type stellar X-ray sources, we discovered a high fraction of multiple systems. In this paper we investigate the orbital elements and kinematic properties of three new spectroscopic triple systems, along with the spectral types and astrophysical parameters (T_eff_, logg, vsini, log N(Li)) of their components. We conducted follow-up optical observations of these systems, both photometric and spectroscopic ones at high resolution. We used a synthetic approach and the cross-correlation method to derive most of the stellar parameters.
- ID:
- ivo://CDS.VizieR/J/A+A/413/293
- Title:
- Radial velocities of RZ Cas
- Short Name:
- J/A+A/413/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In a first report on the results of a multi-site campaign in 2001 of photometric and spectroscopic observations of the active semi-detached Algol-type system RZ Cas, we concentrate on the radial velocity (RV) variations. Using weak absorption lines we obtain an improved orbital solution for both components. In the orbital RV curve we observe a strong, asymmetric rotation effect. For the first time we detect rapid spectroscopic multi-mode pulsations in an Algol system. Whereas the photometrically observed oscillations were dominated by monoperiodic pulsations at frequency 64.19c/d until the year 2000, we find in 2001 a multiperiodic behaviour with two dominant frequencies of f1=56.600c/d and f2=64.189c/d. Both modes show amplitude variations over the orbital phase with a minimum at orbital phases phi=0.6-0.8 and a maximum just after the primary minimum (f2) and at phi=0.25 (f1). The different shape of amplitude modulation of the f1 and f2 modes points to different (l,m) mode structures. The modulation itself can be explained by assuming a variable extinction due to gas streams and an inhomogeneous accretion annulus that weakens the light from different regions of the primary depending on its orbital position.
- ID:
- ivo://CDS.VizieR/J/A+A/498/627
- Title:
- Radial velocities of SB with M giant
- Short Name:
- J/A+A/498/627
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is a follow-up of the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey. We aim at extending the orbital data available for binaries with M giant primaries. The data will be used in the companion papers of this series to (i) derive the binary frequency among M giants and compare it to that of K giants (Paper II, Frankowski et al., 2009A&A...498..479F), and (ii) analyse the eccentricity-period diagram and the mass-function distribution (Paper III, Jorissen et al., 2009A&A...498..489J). Keplerian solutions are fitted to radial-velocity data. However, for several stars, no satisfactory solution could be found, despite the fact that the radial-velocity standard deviation is larger than the instrumental error, because M giants suffer from intrinsic radial-velocity variations due to pulsations. We show that these intrinsic radial-velocity variations can be linked with both the average spectral-line width and the photometric variability. We present an extensive collection of spectroscopic orbits for M giants, with 12 new orbits, plus 17 from the literature. Moreover, to illustrate the fact that the large radial-velocity jitter present in Mira and semi-regular variables may easily be confused with orbital variations, we also present examples of pseudo-orbital variations (in S UMa, X Cnc and possibly in HD 115521, a former IAU radial-velocity standard). Because of this difficulty, M giants involving Mira variables were excluded from our monitored sample. We finally show that the majority of M giants detected as X-ray sources are actually binaries.
- ID:
- ivo://CDS.VizieR/J/ApJS/162/207
- Title:
- Radial velocities of solar-type stars
- Short Name:
- J/ApJS/162/207
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied for duplicity the 167 F7-G8 IV or V primaries within 25pc of the Sun according to their Hipparcos parallaxes and between declinations of -30{deg} and +75{deg}.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2055
- Title:
- Radial velocities of southern SIM grid stars
- Short Name:
- J/MNRAS/446/2055
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present analysis of precision radial velocities (RV) of 1134 mostly red giant stars in the southern sky, selected as candidate astrometric grid objects for the Space Interferometry Mission (SIM). Only a few (typically, two or three) spectroscopic observations per star have been collected, with the main goal of screening binary systems. The estimated rate of spectroscopic binarity in this sample of red giants is 32 per cent at the 0.95 confidence level, and 46 per cent at the 0.75 confidence. The true binarity rate is likely to be higher, because our method is not quite sensitive to very wide binaries and low-mass companions. The estimated lower and upper bounds of stellar RV jitter for the entire sample are 24 and 51m/s, respectively; the adopted mean value is 37m/s. A few objects of interest are identified with large variations of RV, implying abnormally high mass ratios.
- ID:
- ivo://CDS.VizieR/J/A+A/319/481
- Title:
- Radial velocities of 10 spectroscopic binaries
- Short Name:
- J/A+A/319/481
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new orbits for ten (single-lined) spectroscopic binaries in seven open clusters: NGC 2489, 2567, 3033, 5822, 6134, 6664 and IC 2488 based on 243 individual radial velocities obtained with the southern CORAVEL scanner. The orbital periods range from 98.5 to 3566 days. The shortest-period orbit is circular, as expected. Seven of the binaries are confirmed cluster members, one is a possible member, and two are clearly non-members. Maximum masses from photometric separation and minimum masses from the spectroscopic orbits define the mass of the secondaries within an interval of M_max_-M_min_=0.5M_{sun}_. NGC 6664 #54 seems to have a rather massive secondary (M>3M_{sun}_), but the UBV colours appear normal for a luminous red giant, while significantly bluer (B-V) and (U-B) colours would be expected. It could be a triple system, the secondary being itself a short period binary. This paper brings the number of orbits published in this programme to 53, 45 of which are confirmed red-giant cluster members and 8 are non-members
- ID:
- ivo://CDS.VizieR/J/AJ/145/41
- Title:
- Radial velocities of 33 spectroscopic binaries
- Short Name:
- J/AJ/145/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Orbital elements of 37 single-lined spectroscopic binary systems (SB1s) and 5 double-lined spectroscopic binary systems (SB2s) were determined using high-dispersion spectroscopy. To determine the orbital elements accurately, we carried out precise Doppler shift measurements using the HIgh Dispersion Echelle Spectrograph mounted on the Okayama Astrophysical Observatory 1.88 m telescope. We achieved a radial-velocity precision of ~10 m.s^-1^ over seven years of observations. The targeted binaries have spectral types between F5 and K3, and are brighter than the 7th magnitude in the V band. The orbital elements of 28 SB1s and 5 SB2s were determined at least 10 times more precisely than previous measurements. Among the remaining nine SB1s, five objects were found to be single stars, and the orbital elements of four objects were not determined because our observations did not cover the entire orbital period. We checked the absorption lines from the secondary star for 28 SB1s and found that three objects were in fact SB2s.
