Vibrational excitation of H2 in intense ultraviolet fluxes

We study the vibrational excitation of H2 in intense ultraviolet radiation fields. The radiative cascade through bound levels of the ground electronic state, following absorption of Lyman and Werner band photons, is modified to include effects of ''multiple pumping'' and direct photodissociation from the high vibrational levels. Although the column densities in the excited vibrational levels (v> or =1) produced by UV pumping appear too low to explain the recently observed Orion quadrupole emission lines, it is suggested that the far-red lines in the (3-0) and (4-0) bands, produced by UV pumping from O stars near dense molecular clouds, may be detectable