The relations between the luminosities M _ { V } , the metallicities [ Fe / H ] , the Galactocentric radii R , and the central concentration indices c of Galactic globular clusters are discussed .
It is found that the most luminous clusters rarely have collapsed cores .
The reason for this might be that the core collapse time scales for such populous clusters are greater than the age of the Galaxy .
Among those clusters , for which the structure has not been modified by core collapse , there is a correlation between central concentration and integrated luminosity , in the sense that the most luminous clusters have the strongest central concentration .
The outermost region of the Galaxy with R > 10 kpc was apparently not able to form metal-rich ( [ Fe / H ] > -1.0 ) globular clusters , whereas such clusters ( of which Ter 7 is the prototype ) were able to form in some nearby dwarf spheroidal galaxies .
It is not yet clear how the popular hypothesis that globular clusters were initially formed with a single power law mass spectrum can be reconciled with the observation that both ( 1 ) Galactic globular clusters with R > 80 kpc , and ( 2 ) the globulars associated with the Sagittarius dwarf , appear to have bi-modal luminosity functions .