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arXiv · 1308.6238

A Galaxy Model from 2MASS Star Counts in the Whole Sky Including the Plane

Priscilla Polido·Francisco Jablonski·Jacques Lépine
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Abstract

We use the star counts model of Ortiz & Lépine (1993) to perform an unprecedented exploration of the most important galactic parameters comparing the predicted counts with the 2MASS observed star counts in the J, H and K_S bands for a grid of positions covering the whole sky. The comparison is made using a grid of lines-of-sight given by the HEALPix pixelization scheme. The resulting best fit values for the parameters are: (2120 +- 200) pc for the radial scale length and (205 +- 40) pc for the scale height of the thin disk, with a central hole of (2070_{-800}^{+2000}) pc for the same disk; (3050 +- 500) pc for the radial scale length and (640 +- 70) pc for the scale height of the thick disk; (400 +- 100) pc for the central dimension of the spheroid, (0.0082 +- 0.0030) for the spheroid to disk density ratio, and (0.57 +- 0.05) for the oblate spheroid parameter.

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Priscilla Polido, Francisco Jablonski, Jacques Lépine. 2013-08-28. A Galaxy Model from 2MASS Star Counts in the Whole Sky Including the Plane. https://doi.org/10.1088/0004-637x%2F778%2F1%2F32

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