Description
Deep high-resolution JHK images of a 2'x2' field around the OB association A24 near the 7kpc spiral arm in M31 were measured to yield photometric data of more than 3000 stars with the faintest magnitude being J=21.3, H=20.5, and K=19.6. The photometric data for the 1037 stars that are brightest in the K band are presented. Judging from the color-magnitude and the two-color diagrams, we find that the majority of the observed stars are AGB stars including large-amplitude variables. They are distributed smoothly over the observed field, and we find no clear evidence of varying extinction over the field for these red stars. The present sample includes bright AGB stars of M_K_<=-8 and about 30 young blue objects of (J-H)<0.75 that are brighter than M_J_~=-6.5.
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