@article{oai:nagoya.repo.nii.ac.jp:00005486,
 author = {Ishikawa, T. and Hayashi, D. and Sasaki, K. and Kadota, K.},
 issue = {19},
 journal = {Applied Physics Letters},
 month = {May},
 note = {A diagnostic scheme for the measurement of the O^- density in afterglow plasmas is proposed and demonstrated. The present method is based on the fact that excited oxygen atoms (O^*) are produced by mutual neutralization between positive and negative ions (O^+O^-→O^*1+O). The absolute value of the emission coefficient ε_n due to O^*→O+hν is determined by visible emission spectroscopy with a calibrated detection system. The O^+ density n_O^+ is measured by a Langmuir probe combined with mass spectrometry. With the rate coefficient for the above reaction k_n , the O^- density can be evaluated as n_{O^-}=ε_n /(k_nn_{O^+}). In the present letter, the rate coefficient k_n has been determined experimentally from n_{O^-} measured by probe-assisted laser photodetachment.},
 pages = {2391--2393},
 title = {Determination of negative ion density with optical emission spectroscopy in oxygen afterglow plasmas},
 volume = {72},
 year = {1998}
}