Chandra X-ray observation of the H ii region Gum 31 in the Carina nebula complex T. Preibisch, M. Mehlhorn, L. Townsley, P. Broos and T. Ratzka A&A, 564 (2014) A120 Published online: 16 April 2014 DOI: 10.1051/0004-6361/201323133