Deep MMT Transit Survey of the Open Cluster M37. I. Observations and Cluster Parameters

We have conducted a deep ( -->15 r 23), 20 night survey for transiting planets in the intermediate-age open cluster M37 (NGC 2099) using the Megacam wide-field mosaic CCD camera on the 6.5 m MMT. In this paper we describe the observations and data reduction procedures for the survey and analyze the stellar content and dynamical state of the cluster. By combining high-resolution spectroscopy with existing -->BVICKs and new gri color-magnitude diagrams, we determine the fundamental cluster parameters: -->t = 485 ± 28 Myr without overshooting ( -->t = 550 ± 30 Myr with overshooting), -->E(B − V) = 0.227 ± 0.038, -->(m − M)V = 11.57 ± 0.13, and -->[ M/H ] = + 0.045 ± 0.044, which are in good agreement with, although more precise than, previous measurements. We determine the mass function down to 0.3 M☉ and use this to estimate the total cluster mass of -->3640 ± 170 M☉.

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