MEASUREMENT OF HANLE EFFECT FOR OH RADICAL

We have used the coincidence of the Zn I 3072.06 line with the R12(1) line of the (0, 0) band in the OH A+2-X 2 ultraviolet system to perform a measurement of the molecular Hanle effect on the K=2, J=32 rotational level of the excited state. The OH was formed by the reaction H + NO2 OH + NO, and the Hanle linewidth is extrapolated to zero pressure of H2 and NO2. The half-width is found to be 258 36 mG and the pressure broadening of the linewidth corresponds to 13 7 mG/m Torr of NO2 pressure and 5.2 0.8 mG/m Torr of H2 pressure. This linewidth gives a value of g=(2.200.27)×10-7 sec for this excited state of the OH molecule. © 1969 The American Physical Society.