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Extinction map of the Chamaeleon I molecular cloud with DENIS star counts

L. Cambresy·N. Epchtein·E. Copet·B. de Batz·S. Kimeswenger·T. Le Bertre·D. Rouan·D. Typhene
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Abstract

Massive, large scale star counts in the J band provided by the Deep Near Infrared Survey of the Southern Sky (DENIS) are used for the first time to draw out an extinction map of the Chamaeleon I dark cloud. We derived a 2 arcminutes resolution map of the cloud from J star counts within an area of 1.5 x 3 degres around the centre of the cloud using an adaptive grid method and applying a wavelet decomposition. A comparison of our extinction map with the cold contribution of the IRAS 100 microns emission shows an almost perfect matching. It is shown that J star counts supersede optical counts on Schmidt plate where Av > 4.

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L. Cambresy, N. Epchtein, E. Copet, B. de Batz, S. Kimeswenger, T. Le Bertre, D. Rouan, D. Typhene. 1997-06-04. Extinction map of the Chamaeleon I molecular cloud with DENIS star counts. https://arxiv.org/abs/astro-ph/9706035

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