Stellar Radial Velocities in the Old Open Cluster M67 (NGC 2682). II. The Spectroscopic Binary Population

In 1971 Roger Griffin and Jim Gunn began monitoring the radial velocities of most of the members brighter than the main-sequence turnoff in the old open cluster M67, primarily using the 200-inch Hale Telescope. In 1982 the torch was passed to Dave Latham and Bob Mathieu, who began monitoring many of the same stars with the 1.5-meter Tillinghast Reflector and the Multiple-Mirror Telescope on Mt. Hopkins. We have successively combined these two sets of data, plus some additional CORAVEL velocities kindly provided by Michel Mayor, to obtain 20 years of time coverage (e.g. Mathieu et al. 1986). Among the stars brighter than magnitude V = 12.7 we have already published orbits for 22 spectroscopic binaries (Mathieu et al. 1990). At Mt. Hopkins an extension of this survey to many of the cluster members down to magnitude V = 15.5 has already yielded thirteen additional orbital solutions, with the promise of many more to come.

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KELT-9 as an Eclipsing Double-lined Spectroscopic Binary: A Unique and Self-consistent Solution to the System

The Astronomical Journal ◽

10.3847/1538-3881/ac32c7 ◽

2022 ◽

Vol 163 (2) ◽

pp. 40

Author(s):

Anusha Pai Asnodkar ◽

Ji Wang ◽

B. Scott Gaudi ◽

P. Wilson Cauley ◽

Jason D. Eastman ◽

...

Keyword(s):

Radial Velocities ◽

Data Sets ◽

Dynamical Mass ◽

Orbital Inclination ◽

Hot Jupiters ◽

Atmospheric Escape ◽

Spectroscopic Binary ◽

Consistent Solution ◽

Using Data ◽

In Transit

Abstract Transiting hot Jupiters present a unique opportunity to measure absolute planetary masses due to the magnitude of their radial velocity signals and known orbital inclination. Measuring planet mass is critical to understanding atmospheric dynamics and escape under extreme stellar irradiation. Here we present the ultrahot Jupiter system KELT-9 as a double-lined spectroscopic binary. This allows us to directly and empirically constrain the mass of the star and its planetary companion without reference to any theoretical stellar evolutionary models or empirical stellar scaling relations. Using data from the PEPSI, HARPS-N, and TRES spectrographs across multiple epochs, we apply least-squares deconvolution to measure out-of-transit stellar radial velocities. With the PEPSI and HARPS-N data sets, we measure in-transit planet radial velocities using transmission spectroscopy. By fitting the circular orbital solution that captures these Keplerian motions, we recover a planetary dynamical mass of 2.17 ± 0.56 M J and stellar dynamical mass of 2.11 ± 0.78 M ⊙, both of which agree with the discovery paper. Furthermore, we argue that this system, as well as systems like it, are highly overconstrained, providing multiple independent avenues for empirically cross-validating model-independent solutions to the system parameters. We also discuss the implications of this revised mass for studies of atmospheric escape.

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The O-type spectroscopic binary system HD 93206

Symposium - International Astronomical Union ◽

10.1017/s0074180900013607 ◽

1979 ◽

Vol 83 ◽

pp. 277-280 ◽

Cited By ~ 1

Author(s):

Nancy D. Morrison ◽

Peter S. Conti

Keyword(s):

Binary System ◽

Light Curve ◽

Mass Loss ◽

Massive Stars ◽

Radial Velocities ◽

Mass Determination ◽

Spectroscopic Binary ◽

The Masses

The star HD 93206 (=QZ Carinae) is a double-lined (Conti et al. 1977), eclipsing (Moffat and Seggewiss 1972) binary with a period of 6 d. Walborn (1973) classified it 09.7Ib:(n). Since the star is probably a member of the cluster Collander 228 (which is near η Carinae), its distance can be assumed to be 2600 pc. In principle, one can determine the masses of the components of HD 93206 from observations of the radial velocities and the light curve, and a spectroscopic orbit is the object of this investigation. A mass determination for an evolved star such as this one is especially important for checking recently computed evolutionary tracks with mass loss for massive stars (de Loore et al. 1977, Chiosi et al. 1978, Dearborn et al. 1978).

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Spectroscopic Binaries in the Open Cluster M67

International Astronomical Union Colloquium ◽

10.1017/s025292110000628x ◽

1992 ◽

Vol 135 ◽

pp. 155-157 ◽

Cited By ~ 4

Author(s):

David W. Latham ◽

Robert D. Mathieu ◽

Alejandra A.E. Milone ◽

Robert J. Davis

Keyword(s):

Circular Orbit ◽

Main Sequence ◽

Open Cluster ◽

Radial Velocities ◽

Spectroscopic Binaries ◽

Eccentric Orbit ◽

Circular Orbits ◽

Blue Stragglers ◽

Short Period ◽

Blue Straggler

AbstractFor almost 400 members of M67 we have accumulated about 5,000 precise radial velocities. Already we have orbital solutions for more than 32 spectroscopic binaries in M67. Many of these orbits were derived by combining the Palomar and CfA observations, thus extending the time coverage to more than 20 years. The distribution of eccentricity versus period shows evidence for tidal circularization on the main sequence. The transition from circular orbits is fairly clean. Excluding the blue stragglers, the first eccentric orbit has a period of 11.0 days, while the last circular orbit has a period of 12.4 days. For longer periods the distribution of eccentricity is the same as for field stars. The blue straggler S1284 has an eccentric orbit despite its short period of 4.2 days.

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WIYN Open Cluster Study LXXIX. M48 (NGC 2548) I. Radial Velocities, Rotational Velocities, and Metallicities of Stars in the Open Cluster M48 (NGC 2548)

The Astronomical Journal ◽

10.3847/1538-3881/ab83ef ◽

2020 ◽

Vol 159 (5) ◽

pp. 220

Author(s):

Qinghui Sun ◽

Constantine P. Deliyannis ◽

Aaron Steinhauer ◽

Bruce A. Twarog ◽

Barbara J. Anthony-Twarog

Keyword(s):

Open Cluster ◽

Radial Velocities

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WIYN OPEN CLUSTER STUDY. LXVI. SPECTROSCOPIC BINARY ORBITS IN THE YOUNG OPEN CLUSTER M35 (NGC 2168)

The Astronomical Journal ◽

10.1088/0004-6256/150/1/10 ◽

2015 ◽

Vol 150 (1) ◽

pp. 10 ◽

Cited By ~ 12

Author(s):

E. M. Leiner ◽

R. D. Mathieu ◽

N. M. Gosnell ◽

A. M. Geller

Keyword(s):

Open Cluster ◽

Spectroscopic Binary ◽

Young Open Cluster

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RADIAL VELOCITIES AND METALLICITIES OF RED GIANT STARS IN THE OLD OPEN CLUSTER NGC 7762

The Astronomical Journal ◽

10.3847/1538-3881/152/6/224 ◽

2016 ◽

Vol 152 (6) ◽

pp. 224 ◽

Cited By ~ 4

Author(s):

Giovanni Carraro ◽

Eugene A. Semenko ◽

Sandro Villanova

Keyword(s):

Open Cluster ◽

Radial Velocities ◽

Giant Stars ◽

Red Giant Stars ◽

Red Giant

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Solving the distance discrepancy for the open cluster NGC 2453

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935243 ◽

2019 ◽

Vol 626 ◽

pp. A10 ◽

Cited By ~ 2

Author(s):

D. González-Díaz ◽

C. Moni Bidin ◽

E. Silva-Villa ◽

G. Carraro ◽

D. Majaess ◽

...

Keyword(s):

Planetary Nebula ◽

Open Cluster ◽

Independent Method ◽

Radial Velocities ◽

Line Of Sight ◽

Fundamental Parameters ◽

Data Release ◽

Cluster Distance ◽

Ubvri Photometry ◽

Good Agreement

Context. The open cluster (OC) NGC 2453 is of particular importance since it has been considered to host the planetary nebula (PN) NGC 2452, however their distances and radial velocities are strongly contested. Aims. In order to obtain a complete picture of the fundamental parameters of the OC NGC 2453, 11 potential members were studied. The results allowed us to resolve the PN NGC 2452 membership debate. Methods. Radial velocities for the 11 stars in NGC 2453 and the PN were measured and matched with Gaia data release 2 (DR2) to estimate the cluster distance. In addition, we used deep multi-band UBVRI photometry to get fundamental parameters of the cluster via isochrone fitting on the most likely cluster members, reducing inaccuracies due to field stars. Results. The distance of the OC NGC 2453 (4.7 ± 0.2 kpc) was obtained with an independent method solving the discrepancy reported in the literature. This result is in good agreement with an isochrone fitting of 40–50 Myr. On the other hand, the radial velocity of NGC 2453 (78 ± 3 km s−1) disagrees with the velocity of NGC 2452 (62 ± 2 km s−1). Our results show that the PN is a foreground object in the line of sight. Conclusions. Due to the discrepancies found in the parameters studied, we conclude that the PN NGC 2452 is not a member of the OC NGC 2453.

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The Unprecedented Light Variations of NGC 2346

Symposium - International Astronomical Union ◽

10.1017/s0074180900093554 ◽

1983 ◽

Vol 103 ◽

pp. 59-60

Author(s):

R.H. Méndez ◽

R. Gathier ◽

V. S. Niemela

Keyword(s):

Spectral Type ◽

Planetary Nebula ◽

Orbital Motion ◽

Central Star ◽

Primary Component ◽

Radial Velocities ◽

Spectroscopic Binary ◽

Light Minimum ◽

Photoelectric Measurements ◽

Light Maximum

The central star of the planetary nebula NGC 2346 is now well confirmed as a single-lined spectroscopic binary, with P = 16d (Méndez and Niemela 1981, Ap. J., 250, 240). Unexpected photometric variations were recently reported by L. Kohoutek (1982, IAU Circular 3667). From additional photoelectric measurements and visual estimates we have found that these variations are periodic, with the same period as the orbital motion of the A-type primary component. From previous observations we can ascertain that such variations did not exist before, and must have started in 1981. The light minimum occurs at phase 0.75, that is to say when the A-type component is moving towards us. Radial velocities measured on spectrograms obtained during the light minimum are more positive, by about 40 km s−1, than expected from the orbital motion; while the radial velocities corresponding to the light maximum agree with what is expected from the orbital motion. The spectral type of the A-type star does not change significantly as a function of brightness.

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