Radial-velocity orbits for six single-line spectroscopic binaries

Abstract Single-line spectroscopic binaries have recently contributed to stellar-mass black hole discovery, independently of the X-ray transient method. We report the identification of a single-line binary system, LTD064402+245919, with an orbital period of 14.50 days. The observed component is a subgiant with a mass of 2.77 ± 0.68 M ⊙, radius 15.5 ± 2.5 R ⊙, effective temperature T eff 4500 ± 200 K, and surface gravity log g 2.5 ± 0.25 dex. The discovery makes use of the Large Sky Area Multi-Object fiber Spectroscopic Telescope time-domain and Zwicky Transient Facility survey. Our general-purpose software pipeline applies a Lomb–Scargle periodogram to determine the orbital period and uses machine learning to classify the variable type from the folded light curves. We apply a combined model to estimate the orbital parameters from both the light and radial velocity curves, taking constraints on the primary star mass, mass function, and detection limit of secondary luminosity into consideration. We obtain a radial velocity semiamplitude of 44.6 ± 1.5 km s−1, mass ratio of 0.73 ± 0.07, and an undetected component mass of 2.02 ± 0.49 M ⊙ when the type of the undetected component is not set. We conclude that the inclination is not well constrained, and that the secondary mass is larger than 1 M ⊙ when the undetected component is modeled as a compact object. According to our investigations using a Monte Carlo Markov Chain simulation, increasing the spectra signal-to-noise ratio by a factor of 3 would enable the secondary light to be distinguished (if present). The algorithm and software in this work are able to serve as general-purpose tools for the identification of compact objects quiescent in X-rays.

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Masses of the components of SB2 binaries observed with Gaia – V. Accurate SB2 orbits for 10 binaries and masses of the components of 5 binaries

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1571 ◽

2020 ◽

Vol 496 (2) ◽

pp. 1355-1368

Author(s):

J-L Halbwachs ◽

F Kiefer ◽

Y Lebreton ◽

H M J Boffin ◽

F Arenou ◽

...

Keyword(s):

Radial Velocity ◽

Binary Stars ◽

Main Sequence ◽

Spectroscopic Binaries ◽

Orbital Elements ◽

Evolved Stars ◽

The Individual ◽

The Masses ◽

Stellar Masses ◽

Selection Of

ABSTRACT Double-lined spectroscopic binaries (SB2s) are one of the main sources of stellar masses, as additional observations are only needed to give the inclinations of the orbital planes in order to obtain the individual masses of the components. For this reason, we are observing a selection of SB2s using the SOPHIE spectrograph at the Haute-Provence observatory in order to precisely determine their orbital elements. Our objective is to finally obtain masses with an accuracy of the order of one per cent by combining our radial velocity (RV) measurements and the astrometric measurements that will come from the Gaia satellite. We present here the RVs and the re-determined orbits of 10 SB2s. In order to verify the masses, we will derive from Gaia, we obtained interferometric measurements of the ESO VLTI for one of these SB2s. Adding the interferometric or speckle measurements already published by us or by others for four other stars, we finally obtain the masses of the components of five binary stars, with masses ranging from 0.51 to 2.2 solar masses, including main-sequence dwarfs and some more evolved stars whose location in the HR diagram has been estimated.

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Study of Spectroscopic Binaries with the Objective Prism Method

International Astronomical Union Colloquium ◽

10.1017/s025292110000988x ◽

1983 ◽

Vol 62 ◽

pp. 104-107

Author(s):

Frank Gieseking

Keyword(s):

Radial Velocity ◽

Frequency Distribution ◽

Radial Velocities ◽

Spectroscopic Binaries ◽

Steep Decrease ◽

Visual Magnitude ◽

Objective Prism ◽

The Individual ◽

Large Telescopes

The frequency distribution of SB’s over apparent visual magnitude emerging from the catalogue of Batten et. al. (1978) shows a very steep decrease of the number of spectroscopically detected SB’s already for such bright stars of magnitude 7. Considering the number of all stars in the individual magnitude intervals, we find a kind of completeness parameter of the spectroscopic surveys: If we scale it somewhat optimistically at 100% between 0 and 3 mag, we see a 50% decrease of the completeness of our knowledge of stellar radial velocities already for stars fainter than 4.5 mag.This situation is mainly due to the fact that the measurement of radial velocities with conventional slit spectrographs is extremely laborious, requiring long exposure times at large telescopes for the exposure of only one spectrum at a time. – Therefore more efficient methods for radial velocity determinations of fainter stars are urgently needed.

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The nature of the NGC 2546: Not one but two open clusters

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936294 ◽

2020 ◽

Vol 633 ◽

pp. A146 ◽

Cited By ~ 1

Author(s):

A. D. Alejo ◽

J. F. González ◽

M. E. Veramendi

Keyword(s):

Radial Velocity ◽

Binary Stars ◽

Open Cluster ◽

Open Clusters ◽

Spectroscopic Binaries ◽

Physical Parameters ◽

Distance Modulus ◽

Cluster Membership ◽

Spectroscopic Observations ◽

Astrometric Data

Context. As part of a broader project on the role of binary stars in clusters, we present a spectroscopic study of the open cluster NGC 2546, which is a large cluster lacking previous spectroscopic analysis. Aims. We report the finding of two open clusters in the region of NGC 2546. For the two star groups, we determine radial velocity, parallax, proper motion, reddening, distance modulus, and age, using our spectroscopic observations and available photometric and astrometric data, mainly from the second Gaia data release (Gaia-DR2). We also determine the orbit of four spectroscopic binaries in these open clusters. Methods. From mid-resolution spectroscopic observations for 28 stars in the NGC 2546 region, we determined radial velocities and evaluate velocity variability. To analyze double-lined spectroscopic binaries, we used a spectral separation technique and fit the spectroscopic orbits using a least-squares code. The presence of two stellar groups is suggested by the radial velocity distribution and confirmed by available photometric and astrometric data. We applied a multi-criteria analysis to determine cluster membership, and obtained kinematic and physical parameters of the clusters. Results. NGC 2546 is actually two clusters, NGC 2546A and NGC 2546B, which are not physically related to each other. NGC 2546A has an age of about 180 Myr and a distance of 950 pc. It has a half-number radius of 8 pc and contains about 480 members brighter than G = 18 mag. NGC 2546B is a very young cluster (<10 Myr) located at a distance of 1450 pc. It is a small cluster with 80 members and a half-number radius of 1.6 pc. Stars less massive than 2.5 M⊙ in this cluster would be pre-main-sequence objects. We detected four spectroscopic binaries and determined their orbits. The two binaries of NGC 2546A contain chemically peculiar components: HD 68693 is composed of two mercury-manganese stars and HD 68624 has a Bp silicon secondary. Among the most massive objects of NGC 2546B, there are two binary stars: HD 68572, with P = 124.2 d, and CD -37 4344 with P = 10.4 d.

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A Spectroscopic and Photometric Survey for Pre-Main Sequence Binaries

Symposium - International Astronomical Union ◽

10.1017/s0074180900225187 ◽

2001 ◽

Vol 200 ◽

pp. 165-168 ◽

Cited By ~ 3

Author(s):

Eike W. Guenther ◽

Viki Joergens ◽

Ralph Neuhäuser ◽

Guillermo Torres ◽

Natalie Stout Batalha ◽

...

Keyword(s):

Radial Velocity ◽

Main Sequence ◽

Spectroscopic Binaries ◽

Main Sequence Stars ◽

Current State ◽

Short Period ◽

Velocity Variations ◽

The Masses ◽

Stellar Masses ◽

Crucial Test

We give here an overview of the current state of our survey for pre-main sequence spectroscopic binaries. Up to now we have taken 739 spectra of 250 pre-main sequence stars. We find that 8% of the stars show significant radial velocity variations, and are thus most likely spectroscopic binaries. In addition to the targets showing radial velocity variations, 6% of the targets are double-lined spectroscopic binaries i.e., the total fraction of spectroscopic binaries is expected to be about 14%. All short-period SB2s are monitored photometrically in order to search for eclipses. An eclipsing SB2 would allow the direct measurement of the masses of both stellar components. Measurements of the stellar masses together with determinations of the stellar radii are a crucial test of evolutionary tracks of pre-main sequence stars.

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The quest for collapsed/frozen stars in single-line spectroscopic binary systems

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316009601 ◽

2014 ◽

Vol 11 (S308) ◽

pp. 38-45

Author(s):

Virginia Trimble

Keyword(s):

Black Holes ◽

Binary Systems ◽

Massive Star ◽

Spectroscopic Binaries ◽

Single Line ◽

X Ray ◽

Plausible Candidate ◽

Spectroscopic Binary ◽

Galactic Centers ◽

X Ray Binaries

AbstractBlack holes are now commonplace, among the stars, in Galactic centers, and perhaps other places. But within living memory, their very existence was doubted by many, and few chose to look for them. Zeldovich and Guseinov were first, followed by Trimble and Thorne, using a method that would have identified HDE 226868 as a plausible candidate, if it had been in the 1968 catalogue of spectroscopic binaries. That it was not arose from an unhappy accident in the observing program of Daniel M. Popper long before the discovery of X-ray binaries and the identification of Cygnus X-1 with that hot, massive star and its collapsed companion.

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The Spatial Distribution of Spectroscopic Binaries and Blue Stragglers in M 67

Symposium - International Astronomical Union ◽

10.1017/s0074180900043564 ◽

1988 ◽

Vol 126 ◽

pp. 675-676

Author(s):

Robert D. Mathieu ◽

David W. Latham

Keyword(s):

Spatial Distribution ◽

Radial Velocity ◽

Confidence Level ◽

Spectroscopic Binaries ◽

Velocity Variation ◽

Spatial Distributions ◽

Late Type ◽

Single Star ◽

Blue Stragglers ◽

Radial Velocity Variation

Mathieu et al. (1986) have completed an extensive radial-velocity survey of over 100 late-type stars in M 67 with V < 12.8. The spatial distributions of the spectroscopic binaries and single stars (i.e. those stars without detected radial-velocity variation; many of these are undoubtedly binaries, albeit with lower secondary masses) are shown in Fig. 1. The distribution of the binaries is notably more centrally concentrated than the single stars. The two observed distributions derive from distinct parent distributions at the 98% confidence level. The projected half-mass radius of the binaries is 0.9 pc; the half-mass radius of the single stars is 2.4 pc. Indeed, 77% of the binaries lie within the single-star half-mass radius.

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IN-SYNC VI. Identification and Radial Velocity Extraction for 100+ Double-Lined Spectroscopic Binaries in the APOGEE/IN-SYNC Fields

Publications of the Astronomical Society of the Pacific ◽

10.1088/1538-3873/aa77e0 ◽

2017 ◽

Vol 129 (978) ◽

pp. 084201 ◽

Cited By ~ 12

Author(s):

M. A. Fernandez ◽

Kevin R. Covey ◽

Nathan De Lee ◽

S. Drew Chojnowski ◽

David Nidever ◽

...

Keyword(s):

Radial Velocity ◽

Spectroscopic Binaries ◽

Velocity Extraction

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Spectroscopic binaries in M 67

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307011295 ◽

2006 ◽

Vol 2 (14) ◽

pp. 444-445 ◽

Cited By ~ 6

Author(s):

David W. Latham

Keyword(s):

Radial Velocity ◽

Open Cluster ◽

Spectroscopic Binaries ◽

Blue Stragglers

AbstractWe summarize the characteristics of 85 spectroscopic orbits derived from more than two decades of radial-velocity monitoring of stars in the old open cluster M 67, with special emphasis on the blue stragglers and other members that do not fall on the evolutionary tracks expected for isolated single stars.

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