This study examines the 248-nm photodissociation of nitric acid (HNO3) and characterizes the translational energy distribution of the nascent photofragments. Photofragment translational spectroscopy with VUV photoionization detection evidenced one product channel. cleavage of HNO3 to form OH + NO2, and established an upper limit on the contribution from the O + HONO formation channel of 3%. These data contribute an independent measurement to a literature debate regarding the branching between these two channels. (C) 2004 Elsevier B.V. All rights reserved.