1988 Fiscal Year Final Research Report Summary
Higher-order Effects in Electroweak Interactions
| Project/Area Number |
60540184
|
|---|
| 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 | Hiroshima University |
|---|
Principal Investigator |
WAKAIZUMI Seiichi Faculty of Science, Hiroshima University, 理学部, 助教授 (90033886)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Takemi Kure National College of Technology, 教授 (50033832)
KODAIRA Jiro Faculty of Science, Hiroshima University, 理学部, 助手 (40127080)
YONEZAWA Minoru Faculty of Science, Hiroshima University, 理学部, 助教授 (70033800)
MUTA Taizo Faculty of Science, Hiroshima University, 理学部, 教授 (80025353)
|
|---|
| Project Period (FY) |
1985 – 1986
|
| Keywords | Electroweak interaction / Radiative correction / Electroweak theory / Weinberg-Salam theory / Higher-order effect in electroweak interaction / Rare decay / 稀崩壊 / トップ・クォーク |
|---|
| Research Abstract |
The subject of this project is to test SU (2)(]sy.crosprd.[)U(1) standard theory of the electroweak interactions, especially its field-theoretical aspect, by the investigation of the higher-order effects of the theory on various electroweak processes. Under this project, we have done a research into the radiative corrections in the one-loop level to the process e<@D1+@>D1e<@D1-@>D1 W<@D1+@>D1W<@D1-@>D1 and the rare decays of K and B mesons and Z<@D10@>D1-boson. We describe in the following main results of our investigation.
1. In order to calculate the 1-loop corrected amplitude, we develop the general formula for the loop-integrals of the 1-loop vertex function and the box diagram, and we construct a program with which one can algebraically generate the amplitude in the "REDUCE", using the formula, on the basis of the most general amplitude formalism for the vertex function of three-gauge boson coupling and the box diagram. With these tools, we calculate the amplitudes in the Feynman gauge for 1-loop virtual correction for e^+e^- W W^-. Then, soft-photon emission amplitudes are obtained and a procedure of analytically esparating the infra-red divergences from both the vertex function and the box function is established.
2. We study the effect of W-boson width on the total cross-section of e^+e^- W W^- and find its effect to be as much as 5%. this turns out to significantly affect the determination of the W-boson mass from measurement of the total cross-sections. Also, we anlyze the effect of the extra-Z boson inspired by the super-string theory on e^+e^- W W^- . The cross-sections show a remarkable feature and turn out to be detectable by experiments.
|
