THE CENTER OF GRAVITY AND DENSITY PROFILE OF 47-TUCANAE

被引:32
作者
CALZETTI, D [1 ]
DEMARCHI, G [1 ]
PARESCE, F [1 ]
SHARA, M [1 ]
机构
[1] UNIV FLORENCE,SCUOLA DOTTORATO,DIPARTIMENTO ASTRON,I-50121 FLORENCE,ITALY
关键词
GLOBULAR CLUSTERS-INDIVIDUAL-47-TUCANAE; STARS-STATISTICS;
D O I
10.1086/186685
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
From the analysis of HST-FOC images of the globular cluster 47 Tuc, we have determined the position of the center of gravity to be approximately 6'' away from the luminosity center. The luminosity center is mainly determined by an ''asymmetry'' in the luminosity distribution of the stars brighter than m342 congruent-to 16.5. The density profile from the dynamical center shows a central cusp with core radius 8'' and significantly deviates from a King profile up to approximately 13'' from the center. The '' asymmetry'' in the distribution of the bright stars, together with the existence of high-velocity stars, blue stragglers, and millisecond pulsars suggests that the core of 47 Tuc is experiencing a phase of dynamical evolution. Applying the standard two-point correlation analysis, the apparent ''clumpiness'' in the star distribution superposed on the general radial density trend is found to be not significant.
引用
收藏
页码:L1 / &
相关论文
共 21 条
[1]  
AURIERE M, 1988, ASTRON ASTROPHYS, V204, P106
[2]  
AURIERE M, 1989, ASTRON ASTROPHYS, V214, P113
[3]   STAR DISTRIBUTION AROUND A MASSIVE BLACK-HOLE IN A GLOBULAR CLUSTER .2. UNEQUAL STAR MASSES [J].
BAHCALL, JN ;
WOLF, RA .
ASTROPHYSICAL JOURNAL, 1977, 216 (03) :883-907
[4]   A SURVEY OF GALAXY REDSHIFTS .5. THE 2-POINT POSITION AND VELOCITY CORRELATIONS [J].
DAVIS, M ;
PEEBLES, PJE .
ASTROPHYSICAL JOURNAL, 1983, 267 (02) :465-482
[5]  
DEMARCHI G, 1993, IN PRESS APJS
[6]   SURFACE PHOTOMETRY IN CORES OF GLOBULAR-CLUSTERS [J].
DJORGOVSKI, S ;
KING, IR .
ASTROPHYSICAL JOURNAL, 1984, 277 (02) :L49-L52
[7]  
Djorgovski S., 1988, IAU S, P333
[8]  
GUHATHAKURTA P, 1992, IN PRESS AJ
[9]   THE OPTICAL STRUCTURE OF X-RAY GLOBULAR-CLUSTERS [J].
HERTZ, P ;
GRINDLAY, JE .
ASTROPHYSICAL JOURNAL, 1985, 298 (01) :95-&
[10]   X-RAY EVIDENCE FOR WHITE-DWARF BINARIES IN GLOBULAR-CLUSTERS [J].
HERTZ, P ;
GRINDLAY, JE .
ASTROPHYSICAL JOURNAL, 1983, 267 (02) :L83-L87