The Surface Density Profile of NGC 6388: A Good Candidate for Harboring an Intermediate-Mass Black Hole
Author(s)
ASI Sponsor
Lanzoni, B.
Dalessandro, E.
Ferraro, F. R.
Subjects
Date Issued
2007-10-01
Abstract
We have used a combination of HST high-resolution and ground-based wide-field 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 an intermediate concentration ( c = 1.8) and a sizable core radius ( r c = 7.2), a
significant power-law (with slope alpha = -0.2) deviation from flat-core behavior has been detected
within the inner 1. These properties suggest the presence of a central intermediate-mass black
hole. The observed profiles are well reproduced by a multimass isotropic, spherical model, including
a black hole with a mass of 5.7 × 10 3 M ☉ .
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 an intermediate concentration ( c = 1.8) and a sizable core radius ( r c = 7.2), a
significant power-law (with slope alpha = -0.2) deviation from flat-core behavior has been detected
within the inner 1. These properties suggest the presence of a central intermediate-mass black
hole. The observed profiles are well reproduced by a multimass isotropic, spherical model, including
a black hole with a mass of 5.7 × 10 3 M ☉ .
ISSN
0004-637X
Journal
The Astrophysical Journal