The morphology and luminosity function of the Galactic bulge from TMGS star counts

Lopez-Corredoira, M.; Garzon, F.; Hammersley, P.; Mahoney, T.; Calbet, X.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society, vol. 292, p. L15-L19

Fecha de publicación:
11
1997
Número de autores
5
Número de autores del IAC
5
Número de citas
31
Número de citas referidas
25
Descripción
The bulge of the Galaxy is analyzed by inverting K-band star counts from the Two-Micron Galactic Survey in a number of off-plane regions. A total area of about 75 sq deg of sky is analyzed. Assuming a nonvariable luminosity function within the bulge, we derive the top end of the K-band luminosity function and the stellar density function, whose morphology is fitted to triaxial ellipsoids. The luminosity function shows a sharp decrease brighter than MK = -8.0 when compared with the disk population. By fitting ellipsoids, we find that the bulge is triaxial with the major axis in the plane at an angle with the line of sight to the Galactic Center of 12 deg in the first quadrant. The axial ratios are 1:0.54:0.33, and the distance of the sun from the center of the triaxial ellipsoid is 7860 pc.