Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images

Details Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images

Dec 1992

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992aas...18110802y&link_type=abstract

American Astronomical Society, 181st AAS Meeting, #108.02; Bulletin of the American Astronomical Society, Vol. 24, p.1294

Astronomy and Astrophysics

Astronomy

Scientific paper

Hubble Space Telescope Planetary Camera (HST/PC) images of the centers of the dense Galactic globular clusters 47 Tuc and M 15 are presented. We study the radial dependence of the surface density of post-main sequence stars and the surface brightness of the diffuse light of faint unresolved stars below the main sequence turnoff. The radial profile of 47 Tuc is fit well by a King model with core radius r_c=23'' (0.5 pc). The extremely high density of stars near the center of post-core collapse cluster M 15 and the broad wings of the point spread function (PSF) caused by spherical aberration in HST's primary mirror combine to make stellar photometry a painstaking process A technique, specially designed to work in crowded fields, has been used to derive an empirical PSF model and make a fit to the stellar images. Accurate fitting and subtraction of the light of bright red giant stars and estimating the incompleteness as a function of radius and magnitude are crucial to this study. Realistic simulated images have been constructed and analyzed for this purpose. We compare the M 15 data to simulations with a small, but finite core (r_c=2''=0.1pc) and those with mild central cusps (surface density ~ r(-alpha ) , where alpha =0.5-0.8).

Affiliated with

Also associated with

No associations

Rating

Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radial Density Profiles in the Centers of 47 TUC and M15 from HST Images will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1112124