2002/07/12 by Michael D. Albrow, Guido De Marchi, Kailash C. Sahu · 19 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Cluster (spacecraft) #Globular cluster #Initial mass function #Luminosity #Luminosity function #Mass distribution #Mass segregation #Mass spectrum #Stars #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/342920
published in The Astrophysical Journal 579(2), 660-670 (IOP Publishing) · 31 pages including 11 figures, accepted by ApJ
arxiv created 2002/07/12 · openalex publication_date 2002/11/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Hubble Space Telescope imaging of M22 has allowed, for the first time, a detailed and uniform mapping of mass segregation in a globular cluster. Luminosity and mass functions from the turnoff down to the mid to lower main sequence are presented for M22 in annular bins from the center of the cluster out to five core radii. Within the core, a significant enhancement is seen in the proportion of 0.5-0.8 M ☉ stars compared with their numbers outside the core. Numerical modeling of the spatial mass spectrum of M22 shows that the observed degree of mass segregation can be accounted for by relaxation processes within the cluster. The global cluster mass function for M22 is flatter than the Salpeter initial mass function and cannot be represented by a single power law.