Scintillation luminescence for high-pressure xenon gas

Scintillation and ionization yields in xenon gas for 5.49 MeV alpha-particles were measured in the range of pressure from 0.35 to 3.7 MPa and the electric field strength (E) over the number density of xenon atoms (N), E/N from 0 to 5x10-18 V cm2. When our data are normalized at the data point measured by Saito et al., the number of scintillation photons is 2.3x105 while the number of ionization electrons is 2.0x105 at 2.6 MPa and at 3.7x10-18 V cm2. The scintillation and ionization yields of xenon doped with 0.2% hydrogen, High-Pressure Xenon gas[H2-0.2%], at 2.6 MPa was also measured. Scintillation yield of the Xe-H2 mixture gas is 80% as high as that of pure xenon. It is found that the scintillation yield is luminous enough to generate a trigger pulse of the high-pressure xenon time projection chamber, which is expected as a promising MeV Compton gamma-ray camera