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The surface density profile of NGC 6388: a good candidate for harboring an intermediate-mass black hole

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 نشر من قبل Barbara Lanzoni
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف B. Lanzoni




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We have used a combination of high resolution (HST ACS-HRC, ACS-WFC, and WFPC2) and wide-field (ESO-WFI) observations of the galactic globular cluster NGC 6388 to derive its center of gravity, projected density profile, and central surface brightness profile. While the overall projected profiles are well fit by a King model with intermediate concentration (c=1.8) and sizable core radius (rc=7), a significant power law (with slope alpha=-0.2) deviation from a flat core behavior has been detected within the inner 1 arcsecond. These properties suggest the presence of a central intermediate mass black hole. The observed profiles are well reproduced by a multi-mass isotropic, spherical model including a black hole with a mass of ~5.7x10^3 Msol.



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