HYDROGEN FREE
EJ-313
EJ-313 is based on highly purified hexafluorobenzene. Because it is almost free from hydrogen, it is relatively insensitive to fast neutrons, making EJ-313 useful for gamma ray detection in a fast neutron flux.1 According to Jupiter and Parez2 the ratio of the relative gamma ray response to neutron responses for EJ-313 compared to a xylene-based liquid scintillator is 14.5 for 2.6 MeV neutrons and 8.5 for 1 MeV neutrons. Ewen and Gonsior3 found that the gamma ray and neutron efficiencies of this hydrogen-free scintillator to be 25% and 0.4% respectively, relative to those of a NaI(Tl) detector.
| PROPERTIES | EJ-313 |
| Light Output (% Anthracene) | 20 |
| Scintillation Efficiency (photons/1 MeV e-) |
3,060 |
| Wavelength of Maximum Emission (nm) | 425 |
| Decay Time, Short Component (ns) | ~ 3 |
| Bulk Light Attenuation Length (m) | >1 |
| Specific Gravity | 1.619 |
| Refractive Index | 1.38 |
| Flash Point (°C) | 10 |
| Boiling Point (°C at 1 atm) | 80 |
| No. of F Atoms per cm3 (x1022) |
3.14 |
| No. of H Atoms per cm3 (x1020) | 1.02 |
| No. of C Atoms per cm3 (x1022) | 3.15 |
| No. of Electrons per cm3 (x1023) | 4.72 |
References:
1. S. Homma & S. Takemoto, Rev. Sci. Instr. 32, No. 9, 1055 (Sept. 1961).
2. C. P. Jupiter & J. Parez, IEEE Trans. Nucl. Sci., NS-13, (1) 692-703 (1966).
3. K. Ewen & B. Gonsior, Nucl. Instr. & Meth., 99, 573-578 (1972).