Isotope selective photodissociation of N2 by the interstellar radiation field and cosmic rays Alan N. Heays, Ruud Visser, Roland Gredel, Wim Ubachs, Brenton R. Lewis, Stephen T. Gibson and Ewine F. van Dishoeck A&A, 562 (2014) A61 Published online: 06 February 2014 DOI: 10.1051/0004-6361/201322832