The Distribution of Stellar Mass in the Pleiades

Abstract

As part of an effort to understand the origin of open clusters, we present a statistical analysis of the currently observed Pleiades. Starting with a photometric catalog of the cluster, we employ a maximum likelihood technique to determine the mass distribution of its members, including single stars and both components of binary systems. We find that the overall binary fraction for unresolved pairs is 68%. Extrapolating to include resolved systems, this fraction climbs to about 76%, significantly higher than the accepted field-star result. Both figures are sensitive to the cluster age, for which we have used the currently favored value of 125 Myr. The primary and secondary masses within binaries are correlated, in the sense that their ratios are closer to unity than under the hypothesis of random pairing. We map out the spatial variation of the cluster's projected and three-dimensional mass and number densities. Finally, we revisit the issue of mass segregation in the Pleiades. We find unambiguous evidence of segregation, and introduce a new method for quantifying it.

arXiv comment41 pages, 14 figures To Be Published in The Astrophysical Journal

References in corpus (18)

• Galactic Stellar and Substellar Initial Mass Function
• On the variation of the Initial Mass Function
• New catalogue of optically visible open clusters and candidates
• Spectral Irradiance Calibration in the Infrared. XIV: the Absolute Calibration of 2MASS
• On the Formation of Massive Stars
• Keck Spectra of Pleiades Brown Dwarf Candidates and a Precise Determination of the Lithium Depletion Edge in the Pleiades
• Stellar Multiplicity and the IMF: Most Stars Are Single
• Brown dwarfs in the Pleiades cluster : clues to the substellar mass function
• Confirmation of Errors in Hipparcos Parallaxes from HST/FGS Astrometry of the Pleiades
• Near and Mid-IR Photometry of the Pleiades, and a New List of Substellar Candidate Members
• Star Formation in Space and Time: The Orion Nebula Cluster
• The Mass and Structure of the Pleiades Star Cluster from 2MASS
• A Near-Infrared Multiplicity Survey of Class I/Flat-Spectrum Systems in Six Nearby Molecular Clouds
• Proper motion surveys of the young open clusters Alpha Persei and the Pleiades
• Pleiades low-mass brown dwarfs: the cluster L dwarf sequence
• The Pleiades mass function: models versus observations
• The Shapes of Molecular Cloud Cores in Orion
• Cluster Formation in Contracting Molecular Clouds

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• A 5D view of the Alpha Per, Pleiades, and Praesepe clusters
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• On the temporal evolution of the stellar mass function in Galactic clusters
• Revisiting the mass of open clusters with \emph{Gaia} data
• Modelling of the Effects of Stellar Feedback during Star Cluster Formation Using a Hybrid Gas and N-Body Method
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• Survival Rates of Planets in Open Clusters: the Pleiades, Hyades, and Praesepe clusters
• Long-term Spectroscopic Survey of the Pleiades Cluster: The Binary Population
• Reanalysis of nearby open clusters using Gaia DR1/TGAS and HSOY
• Tidal tails of open star clusters as probes to early gas expulsion II: Predictions for Gaia
• The seven sisters DANCe IV. Bayesian hierarchical model
• Star Clusters Under Stress: Why Small Systems Cannot Dynamically Relax
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• Star clusters in the Sh2-132 complex: clues about the connection between embedded and open clusters
• An updated maximum likelihood approach to open cluster distance determination
• The Dynamical Evolution of the Pleiades
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