The effect of a non-Maxwellian distribution on excitation and ionization of hydrogen in solar flares

The effects of the nonthermal collisional excitation and ionization of hydrogen by electron beams on a flaring chromosphere are studied analytically. Owing to strong departures from the Maxwellian distribution, nonthermal effects lead to an increase of the energy deposited in excited and ionized states, which can explain the enhancement of the chromospheric Paschen emission as white-light flares. The results are compared to the semi-empirical results of Aboudarham & Henoux (1986, A&A, 168)