Radial Velocities, Binarity, and Kinematic Membership in the Open Cluster NGC 2516

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

The Astronomical Journal ◽

10.3847/1538-3881/abdd23 ◽

2021 ◽

Vol 161 (4) ◽

pp. 190

Author(s):

Aaron M. Geller ◽

Robert D. Mathieu ◽

David W. Latham ◽

Maxwell Pollack ◽

Guillermo Torres ◽

...

Keyword(s):

Open Cluster ◽

Radial Velocities ◽

Spectroscopic Binary

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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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Radial Velocities and Kinematic Membership in the Open Cluster NGC 3114

The Astronomical Journal ◽

10.1086/320396 ◽

2001 ◽

Vol 121 (5) ◽

pp. 2657-2663 ◽

Cited By ~ 11

Author(s):

Jorge Federico González ◽

Emilio Lapasset

Keyword(s):

Open Cluster ◽

Radial Velocities

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NIR Spectroscopy of the Most Massive Open Cluster in the Galaxy: Westerlund 1

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308015433 ◽

2007 ◽

Vol 3 (S246) ◽

pp. 113-114 ◽

Cited By ~ 2

Author(s):

S. Mengel ◽

L. E. Tacconi-Garman

Keyword(s):

Cluster Expansion ◽

Main Sequence ◽

Velocity Dispersion ◽

Open Cluster ◽

Nir Spectroscopy ◽

Radial Velocities ◽

Main Sequence Stars ◽

Central Wavelength ◽

Cluster Mass ◽

The Galaxy

AbstractUsing ISAAC/VLT, we have obtained individual spectra of all NIR-bright stars in the central 2′ × 2′ of the cluster Westerlund 1 (Wd 1) with a resolution of R ≈ 9000 at a central wavelength of 2.30 μm. This allowed us to determine radial velocities of ten post-main-sequence stars, and from these values a velocity dispersion. Assuming virial equilibrium, the dispersion of σ = 8.4 km/s leads to a total dynamical cluster mass of 1.25 × 105M⊙, comparable to the photometric mass of the cluster. There is no extra-virial motion which would have to be interpreted as a signature of cluster expansion or dissolution.

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