Collisional excitation of O2 by H2: the validity of LTE models in interpreting O2 observations F. Lique, Y. Kalugina, S. Chefdeville, S. Y. T. van de Meerakker, M. Costes and C. Naulin A&A, 567 (2014) A22 Published online: 04 July 2014 DOI: 10.1051/0004-6361/201423957