The radiator gas is a mixture of C4F10 and C5F12. The index of refraction of this mixture was specified to have a value of n-1 = 1850 X 10-6 at 1.25 atm.
The following values for the index of refraction were used (within PMT range: 300nm - 500nm):
C4F10 ----- 1380 (Measured during prototype dev.) C5F12 ----- 1622 (Estimated from liquid phase) The partial pressures should be: C4F10 ---- 0.587 or 557.6 Torr C5F12 ---- 0.413 ro 392.3 Torr It was estimated that 5.81 kg of C5F12 were necessary for one filling of the RICH.(Created 8-May-2000)