| Project/Area Number |
15540380
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
原子・分子・量子エレクトロニクス・プラズマ
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| Research Institution | Faculty of Education, Tokyo Gakugei University |
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Principal Investigator |
NITTA Hideo Tokyo Gakugei University, Faculty of Education, Associate professor, 教育学部, 助教授 (50198529)
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| Project Period (FY) |
2003 – 2004
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| Project Status |
Completed (Fiscal Year 2004)
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| Budget Amount *help |
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2004: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2003: ¥1,600,000 (Direct Cost: ¥1,600,000)
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| Keywords | strong fields / radiation / electron-positron pair production / polarization radiation / synchrotron approximation / チャネリング / 対生成 |
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| Research Abstract |
By applying the standard trajectory method derived by the present investigator and Khokonov, a simple expression is obtained for electron-positron pair production by photons in a strong nonuniform electromagnetic field. The expression depends on two parameters : the invariant field parameter and the "non-dipole" parameter. The former represents the strength of the field while the latter depends on the scattering angle of a produced positron/electron. Our numerical calculations agree well with experimental results.
It is predicted that the pair production rate reaches its maximum at about 10TeV.
As for radiation, we have found that at the small non-dipole parameter limit our radiation formula has no divergence, in contrast to the Bethe-Heitler formula of bremsstrahlung. This is very important findings especially in connection with the Landau-Pomeranchuk effect.
As an alternative radiation process to bremsstrahlung, polarization radiation is important to take into account. We have developed a unified treatment of polarization-radiation-based processes, i.e. the Cherenkov radiation, transition radiation, and coherent polarization radiation (parametric x-ray radiation).
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