Stellar contribution to the Galactic bulge microlensing optical depth

被引：168

作者：

Han, CC ^{[1
]}

Gould, A

机构：

[1] Chungbuk Natl Univ, Inst Basic Sci Res, Dept Phys, Chonju 361763, South Korea

[2] Ohio State Univ, Dept Astron, Columbus, OH 43210 USA

来源：

ASTROPHYSICAL JOURNAL | 2003年 / 592卷 / 01期

关键词：

dark matter; Galaxy : bulge; gravitational lensing; stars : luminosity function; mass function;

D O I：

10.1086/375706

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We estimate the optical depth to self-lensing by stars in the Galactic bulge using the Hubble Space Telescope star counts of Holtzman et al. and Zoccali et al. as extrapolated by Gould into the brown dwarf and remnant regimes and deprojected along the line of sight using the model of Dwek et al. We find a self-lensing optical depth tau (bulge - bulge) = 0.98 x 10(-6). When combined with the lensing of bulge stars by foreground stars in the disk, this yields tau (bulge - total) = 1.63 x 10(-6), in reasonable agreement with the estimates of tau = 2.13 +/- 0.40 x 10(-6) and tau = 1.08 +/- 0.30 x 10(-6) based on observations of clump giants by the MACHO and EROS collaborations.

引用

页码：172 / 175

页数：4

共 34 条

[1] Bulge microlensing optical depth from EROS 2 observations [J].

Afonso, C ;

Albert, JN ;

Alard, C ;

Andersen, J ;

Ansari, R ;

Aubourg, É ;

Bareyre, P ;

Bauer, F ;

Beaulieu, JP ;

Blanc, G ;

Bouquet, A ;

Char, S ;

Charlot, X ;

Couchot, F ;

Coutures, C ;

Derue, F ;

Ferlet, R ;

Fouqué, P ;

Glicenstein, JF ;

Goldman, B ;

Gould, A ;

Graff, D ;

Gros, M ;

Haissinski, J ;

Hamadache, C ;

Hamilton, JC ;

Hardin, D ;

de Kat, J ;

Kim, A ;

Lasserre, T ;

LeGuillou, L ;

Lesquoy, É ;

Loup, C ;

Magneville, C ;

Mansoux, B ;

Marquette, JB ;

Maurice, É ;

Maury, A ;

Milsztajn, A ;

Moniez, M ;

Palanque-Delabrouille, N ;

Perdereau, O ;

Prévot, L ;

Regnault, N ;

Rich, J ;

Spiro, M ;

Tisserand, P ;

Vidal-Madjar, A ;

Vigroux, L ;

Zylberajch, S .

ASTRONOMY & ASTROPHYSICS, 2003, 404 (01) :145-156

[2] The MACHO project: Microlensing optical depth toward the Galactic bulge from difference image analysis [J].

Alcock, C ;

Allsman, RA ;

Alves, DR ;

Axelrod, TS ;

Becker, AC ;

Bennett, DP ;

Cook, KH ;

Drake, AJ ;

Freeman, KC ;

Geha, M ;

Griest, K ;

Lehner, MJ ;

Marshall, SL ;

Minniti, D ;

Nelson, CA ;

Peterson, BA ;

Popowski, P ;

Pratt, MR ;

Quinn, PJ ;

Stubbs, CW ;

Sutherland, W ;

Tomaney, AB ;

Vandehei, T ;

Welch, DL .

ASTROPHYSICAL JOURNAL, 2000, 541 (02) :734-766

[3] The MACHO project: 45 candidate microlensing events from the first-year Galactic bulge data [J].

Alcock, C ;

Allsman, RA ;

Alves, D ;

Axelrod, TS ;

Bennett, DP ;

Cook, KH ;

Freeman, KC ;

Griest, K ;

Guern, J ;

Lehner, MJ ;

Marshall, SL ;

Park, HS ;

Perlmutter, S ;

Peterson, BA ;

Pratt, MR ;

Quinn, PJ ;

Rodgers, AW ;

Stubbs, CW ;

Sutherland, W .

ASTROPHYSICAL JOURNAL, 1997, 479 (01) :119-146

[4]

BELOKUROV V, 2002, APJ, V567, pL119

[5] Is galactic structure compatible with microlensing data? [J].

Binney, J ;

Bissantz, N ;

Gerhard, O .

ASTROPHYSICAL JOURNAL, 2000, 537 (02) :L99-L102

[6] The microlensing optical depth of the COBE bulge [J].

Bissantz, N ;

Englmaier, P ;

Binney, J ;

Gerhard, O .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1997, 289 (03) :651-659

[7] Spiral arms, bar shape and bulge microlensing in the Milky Way [J].

Bissantz, N ;

Gerhard, O .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 330 (03) :591-608

[8]

COX AN, 1999, ALLENS ASTORPHYSICAL, P489

[9] MORPHOLOGY, NEAR-INFRARED LUMINOSITY, AND MASS OF THE GALACTIC BULGE FROM COBE DIRBE OBSERVATIONS [J].

DWEK, E ;

ARENDT, RG ;

HAUSER, MG ;

KELSALL, T ;

LISSE, CM ;

MOSELEY, SH ;

SILVERBERG, RF ;

SODROSKI, TJ ;

WEILAND, JL .

ASTROPHYSICAL JOURNAL, 1995, 445 (02) :716-730

[10] Disk M dwarf luminosity function from Hubble Space Telescope star counts [J].

Gould, A ;

Bahcall, JN ;

Flynn, C .

ASTROPHYSICAL JOURNAL, 1996, 465 (02) :759-768

← 1 2 3 4 →