Related papers: Kinematics and binaries in young stellar aggregate…
We present a kinematic study of the Orion Nebula Cluster based upon radial velocities measured by multi-fiber echelle spectroscopy at the 6.5 meter MMT and Magellan telescopes. Velocities are reported for 1613 stars, with multi-epoch data…
We have searched for visual binaries with projected separations in the range 200-3000 AU (0.1"-1.5") among a sample of 96 stars in the massive young NGC 6611 cluster, 60 of them being subsequently identified as high probability cluster…
We search for mass segregation in the intermediate-aged open cluster NGC 6819 within a carefully identified sample of probable cluster members. Using photometry from the Gaia, 2MASS, and Pan-STARRS surveys as inputs for a Bayesian…
Internal kinematics, spectroscopic binaries and galactic motion are investigated for the trapezium system BD+00.1617 (which lies at the heart of the young open cluster Bochum 2) by means on 73 high resolution Echelle+CCD spectra secured…
Many young extra-galactic clusters have a measured velocity dispersion that is too high for the mass derived from their age and total luminosity, which has led to the suggestion that they are not in virial equilibrium. Most of these…
We present a kinematic analysis of three triple stellar systems belonging to two open clusters: CPD-60{\deg}961 and HD66137 in NGC2516, and HD315031 in NGC6530. All three systems are hierarchical triples with a close binary bound to a third…
We present results from 1078 high resolution spectra of 990 stars in the young open cluster NGC 2264, obtained with the Hectochelle multiobject echelle spectrograph on the 6.5m MMT. We confirm 471 stars as members, based on their radial…
We present an expanded kinematic study of the young cluster NGC 2264 based upon optical radial velocities measured using multi-fiber echelle spectroscopy at the 6.5 meter MMT and Magellan telescopes. We report radial velocities for 695…
We present orbits for 24 binaries in the field of open cluster NGC 2516 (~150 Myr) and 13 binaries in the field of open cluster NGC 2422 (~130 Myr) using results from a multi-year radial velocity survey of the cluster cores. Six of these…
We analyze 9 open clusters with ages in the range 70 Myr to 3.2 Gyr using UCAC2 proper motion data and 2MASS photometry. For each cluster we consider the projected velocity distributions in the core and off-core regions separately. In the…
We present a comprehensive photometric analysis of a young open cluster NGC 1960 (M36) along with the long-term variability study of this cluster. Based on the kinematic data of Gaia DR2, the membership probabilities of 3871 stars are…
We present the first multi-epoch radial velocity study of embedded young massive stars using near-infrared spectra obtained with ISAAC mounted at the ESO Very Large Telescope, with the aim to detect massive binaries. Our 16 targets are…
In the first few Myr the massive stars dynamically interact, produce runaways and affect the initial binary population. Observing and interpreting the dynamics of young massive clusters is key to our understanding of the star formation…
Significant progress has been made toward understanding the formation of massive ($M > 8~$M$_{\odot}$) binaries in close orbits. For example, the detection of a very low velocity dispersion among the massive stars in the young region M17…
Based on a set of over 100 medium- to high-resolution optical spectra collected from 2003 to 2009, we investigate the properties of the O-type star population in NGC6611 in the core of the Eagle Nebula (M16). Using a much more extended data…
The massive (13,000-26,000 Msolar), young (15-30 Myr) Large Magellanic Cloud star cluster NGC 1818 reveals an unexpected increasing binary frequency with radius for F-type stars (1.3-2.2 Msolar). This is in contrast to many older star…
The complexity of composite spectra of close binary star system makes study of the spectra of their component stars extremely difficult. For this reason there exists very little information on the photospheric chemical composition of stars…
Kinematics of 237 Chromospherically Active Binaries (CAB) were studied. The sample is heterogeneous with different orbits and physically different components from F to M spectral type main sequence stars to G and K giants and super giants.…
By studying young open clusters, the mechanisms important for star formation over several Myr can be examined. For example, accretion rate as a function of rotational velocity can be investigated. Similarly, sequential star formation…
Using the Bayesian Analysis of Stellar Evolution-9 (BASE-9) code and Gaia DR3, Pan-STARRS, and 2MASS data, we identify photometric binaries in 35 open clusters (OCs) and constrain their masses. We find a strong correlation between the…