A varying mass-to-light ratio in the galactic center cluster?

被引:16
作者
Saha, P
Bicknell, GV
McGregor, PJ
机构
[1] Mount Stromlo and Siding Spring Observatories, Institute of Advanced Studies, Australian National University, Weston Creek PO, ACT 2611, Private Bag
关键词
Galaxy; center; open clusters and associations; general;
D O I
10.1086/177639
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We reanalyze published kinematic and photometric data for the cool star population in the central 10 pc (240 '') of the Galaxy, while (1) isolating the photometric data appropriate to this population, and (2) properly allowing for projection effects. Under the assumptions that the system is spherical and isotropic, we find that M/L(K) varies from less than or equal to 1 outside a radius of 0.8 pc to >2 at 0.35 pc. This behavior cannot be due to the presence of a central massive black hole. We suggest that such a varying M/L(K) may be due to an increasing concentration of stellar remnants toward the Galactic center. Our derived mass-radius curve confirms the existence of similar to 3 x 10(6) M(.) within 0.35 pc of the Galactic center, and similar to 1.5 x 10(6) M(.) within 0.2 pc. However, the latter estimate is subject to the uncertain distribution of cool stars in this region. We also consider the dynamics of the hot star population close to the Galactic center and show that the velocity dispersion of the He I stars and the surface brightness distribution of the hot stars are consistent with the mass distribution inferred from the cool stars.
引用
收藏
页码:636 / 644
页数:9
相关论文
共 39 条
  • [21] NEUTRAL GAS IN THE CENTRAL 2 PARSECS OF THE GALAXY
    JACKSON, JM
    GEIS, N
    GENZEL, R
    HARRIS, AI
    MADDEN, S
    POGLITSCH, A
    STACEY, GJ
    TOWNES, CH
    [J]. ASTROPHYSICAL JOURNAL, 1993, 402 (01) : 173 - 184
  • [22] ASTRONOMICAL MEASUREMENTS IN INFRARED
    JOHNSON, HL
    [J]. ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, 1966, 4 : 193 - &
  • [23] GALACTIC STRUCTURE FROM THE SPACELAB INFRARED TELESCOPE .3. A DYNAMIC-MODEL FOR THE MILKY-WAY BULGE
    KENT, SM
    [J]. ASTROPHYSICAL JOURNAL, 1992, 387 (01) : 181 - 188
  • [24] THE NUCLEAR CLUSTER OF THE MILKY-WAY - STAR-FORMATION AND VELOCITY DISPERSION IN THE CENTRAL 0.5 PARSEC
    KRABBE, A
    GENZEL, R
    ECKART, A
    NAJARRO, F
    LITZ, D
    CAMERON, M
    KROKER, H
    TACCONIGARMAN, LE
    THATTE, N
    WEITZEL, L
    DRAPATZ, S
    GEBALLE, T
    STERNBERG, A
    KUDRITZKI, R
    [J]. ASTROPHYSICAL JOURNAL, 1995, 447 (02) : L95 - L99
  • [25] A CLUSTER OF HE-I EMISSION-LINE STARS IN THE GALACTIC-CENTER
    KRABBE, A
    GENZEL, R
    DRAPATZ, S
    ROTACIUC, V
    [J]. ASTROPHYSICAL JOURNAL, 1991, 382 (01) : L19 - L22
  • [26] LINDQVIST M, 1992, ASTRON ASTROPHYS, V259, P118
  • [27] HIGH-RESOLUTION OBSERVATIONS OF IONIZED-GAS IN CENTRAL-3 PARSECS OF THE GALAXY - POSSIBLE EVIDENCE FOR INFALL
    LO, KY
    CLAUSSEN, MJ
    [J]. NATURE, 1983, 306 (5944) : 647 - 651
  • [28] MAEDER A, 1988, ASTRON ASTROPHYS SUP, V76, P411
  • [29] STELLAR KINEMATICS IN THE GALACTIC-CENTER
    MCGINN, MT
    SELLGREN, K
    BECKLIN, EE
    HALL, DNB
    [J]. ASTROPHYSICAL JOURNAL, 1989, 338 (02) : 824 - 840
  • [30] CO OVERTONE EMISSION FROM MAGELLANIC CLOUD SUPERGIANTS
    MCGREGOR, PJ
    HILLIER, DJ
    HYLAND, AR
    [J]. ASTROPHYSICAL JOURNAL, 1988, 334 (02) : 639 - 656