Excitation mechanism of the He-I+ laser

Abstract

We have investigated the afterglow decay rates of sixteen iodine ion, I(II), laser lines in spontaneous emissions. All lines originate from the four triplet terms of the 5s25p3(2D0)6p electronic configuration. The variation of the I(II) spontaneous emission decay rates with increasing iodine pressure provides direct evidence that a charge-transfer reaction involving the ground-state atomic helium ion and a ground-state iodine atom is a primary source of excitation for the upper levels of the helium-iodine ion laser. A total velocity-averaged cross section, σ (He+-I), of 3×10−16 cm2 has been measured.