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Reference: 	Cantrell, Zimmer and Tyndall
		Absorption cross sections for water vapor from 183 to 193nm
		Geophys. Res. Lett., 24, 17, 2195-2198, 1997.

H2O + hv -> H + OH

Absorption cross sections for water vapor at 184.9 nm were measured using a
standand low-pressure mercury lamp light source, optically filtered to isolate 
the spectrial region near the emission line. 

Wavelength (nm)    Cross section (1E-20 cm^2 molecule-1)
183.0	16.9
184.0	12.1
185.0	6.78
186.0	4.39
187.0	2.71
188.0	1.77
189.0	1.08
190.0	0.672
191.0	0.464
192.0	0.277
193.0	0.175