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Clusters in the solar neighbourhood: how are they destroyed?

Henny J. G. L. M. Lamers·Mark Gieles
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Abstract

We predict the survival time of initially bound star clusters in the solar neighbourhood taking into account: (1) stellar evolution, (2) tidal stripping, (3) shocking by spiral arms and (4) encounters with giant molecular clouds. We find that the predicted dissolution time is t_dis= 1.7 (M_i/10^4 M_sun)^0.67 Gyr for clusters in the mass range of 10^2 < M_i < 10^5 M_sun, where M_i is the initial mass of the cluster.. The resulting predicted shape of the logarithmic age distribution agrees very well with the empirical one, derived from a complete sample of clusters in the solar neighbourhood within 600 pc. The required scaling factor implies a star formation rate of 400 M_sun/Myr within 600 pc from the Sun or a surface formation rate of 3.5 10^-10 M_sun/(yr pc^2) for stars in bound clusters with an initial mass in the range of 10^2 to 3 10^4 M_sun.

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Henny J. G. L. M. Lamers, Mark Gieles. 2006-06-30. Clusters in the solar neighbourhood: how are they destroyed?. https://doi.org/10.1051/0004-6361%3A20065567

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