Molecular gas heating in Arp 299 M. J. F. Rosenberg, R. Meijerink, F. P. Israel, P. P. van der Werf, E. M. Xilouris and A. Weiß A&A, 568 (2014) A90 Published online: 26 August 2014 DOI: 10.1051/0004-6361/201423707