| 研究生: |
陳建溢 Chien-Yi Chen |
|---|---|
| 論文名稱: |
無R超對稱標準模型中輕子的輻射衰變 Leptonic Radiative decay inSupersymmetry without R-parity |
| 指導教授: |
江祖永
Otto C. W. Kong |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
理學院 - 物理學系 Department of Physics |
| 畢業學年度: | 94 |
| 語文別: | 英文 |
| 論文頁數: | 51 |
| 中文關鍵詞: | 超對稱 |
| 外文關鍵詞: | supersymmetry, R-parity, leptonic radiative decay |
| 相關次數: | 點閱:9 下載:0 |
| 分享至: |
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我們在無R超對稱標準模型中利用數值方法計算 one loop Feynman圖對 μ and τ 的輻射衰變,即 μ → eγ ,τ → eγ , 和 τ → μγ 的貢獻,並對結果做定性的分析。在目前實驗數據的限制下,R 宇稱破缺參數空間的允許範圍已經可以藉由數值上的計算精確地得到。
Ref.[7] 也曾做過類似的研究, 但因為其在計算中對 mass eigenstate couplings 做近似,所以得到的結果並不完全精確。本論文則利用精確的mass eigenstate couplings 來做計算,並對兩者的結果加以比較。我們發現在μ*B 的參數空間中,兩者所得到的結果有明顯的差異。
We present a detail analysis together with exact numerical calculations on one loop contributions
to the branching ratio of the radiative decay of μ and τ , namely μ → e γ, τ → e γ,
and τ → μγ from supersymmtry without R-parity. An exact numerical study is performed
to obtain explicit bounds on the parameters under the present experimental limit. A similar
work has been performed in the Ref.[7], which used electroweak states as an approximation
to the physical particles for the external legs to the loop. However, we use the formula
for exact mass eigenstate couplings to calculate the one loop diagrams. We compare the
results obtained by using these two approaches in the R-parity violating parameter spaces
and discover that they have a sizable difference in the resulted constraints on some μ*B
combinations.
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43
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