1992 Fiscal Year Final Research Report Summary
Lead-fluoride Crystal as Cherenkov Radiator
| Project/Area Number |
03640286
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
核・宇宙線・素粒子
|
|---|
| Research Institution | NATIONAL LABORATORY FOR HIGH ENERGY PHYSICS |
|---|
Principal Investigator |
YOSHIMURA Y KEK, Physics, Prof., 物理研究部, 教授 (50013397)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KANDA M KEK, Radiation, Assistant Prof., 放射線安全管理センター, 助教授 (20150005)
SHINKAWA T KEK, Physics, Assistant Prof., 物理研究部, 助手 (70171064)
OGAWA K KEK, Physics, Associate Prof., 物理研究部, 助教授 (10113416)
|
|---|
| Project Period (FY) |
1991 – 1992
|
| Keywords | Lead-fluoride / Cherenkov / Transmission / Radiation / Damage / Doping |
|---|
| Research Abstract |
Lead fluoride, PbF2, has been investigated on the physical properties such as the transmission, a raiation resistivity, scintillant emission to be used as the Cherenkov radiator in the field of High Energy Physics or Nuclear Physics. The crystal of lead fluoride has a density of 7.77g/cm^<**>3, a radiation length of 0.93cm and a refractive index of 1.85.
First of all several small samples were crystallized from different raw material to manufacture blocks with better transmission. The best ones had the transmission of 84% including surface reflection and the optical cutoff edge of 245nm, which were compared with the published value of 280nm.
The samples of 2cm in diameter and 1cm thick were irradiated to Co-gamma rays to measure the radiation resistivity. They showed for the resistivity on the transmission to be about 1,000 times more than that of lead glass, SF5. Beside the high resistivity, their radiation damage with 10^<**>7 red were perfectly recovered by exposing to UV light for 30minutes. But the damage at 10^<**>8 rad showed a little recover. Then, irradiation to gamma rays of 10^<**>7 rad and exposure to UV light were done repatedly 10 times over. The damage could practically be cured for the total sum of 10^<**>8 rad.
Doping CeF3, CsF, EuF and so on, the scintillation light was searched exposuring UV light, but was not observed except for a EuF sample.
|
