Is galactic structure compatible with microlensing data?

Citation
J. Binney et al., Is galactic structure compatible with microlensing data?, ASTROPHYS J, 537(2), 2000, pp. L99-L102
Citations number
15
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004637X → ACNP
Volume
537
Issue
2
Year of publication
2000
Part
2
Pages
L99 - L102
Database
ISI
SICI code
0004-637X(20000710)537:2<L99:IGSCWM>2.0.ZU;2-P
Abstract
We generalize to elliptical models an argument introduced by Gould, which c onnects the microlensing optical depth toward the Galactic bulge to the Gal actic rotation curve. When applied to the latest value from the MACHO colla boration for the optical depth for microlensing of bulge sources, the argum ent implies that even a barred Galactic model cannot plausibly reconcile th e measured values of the optical depth, the rotation curve, and the local m ass density. Either there is a problem with the interpretation of the micro lensing data or our line of sight to the Galactic center is highly atypical in that it passes through a massive structure with small solid angle as se en from the Galactic center.