The close coincidence between the 13ndash;12P(8) CO laser line andsRR(8,3) transition in the ngr;4band of NH3is used to find the spectral parameters of the absorbing line by fitting the Doppler and Voigt shapes to the appropriate regions of the transmittance curves. The selfhyphen;broadening parameter (linewidth) is found to be (8.11plusmn;0.43) times;10minus;4Torrminus;1cmminus;1. The foreign gas broadening coefficient with respect to N2is measured to be 5.28plusmn;.90. The frequency offset between the laser and the center of the transition is determined to be approximately half the full Doppler width. From the line strength measurement, dgr;mgr;/dgr;Qis found to be 6.3plusmn;1.8 esu, approximately 20percent; smaller than that derived in an earlier determination based on total band strength, rather than that of a single line as is done here. The difference may be due in part to the unavoidable inclusion in the earlier work of the overlapping 2ngr;2band.
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