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Published on: November 15, 2013
New process for charged lepton flavor violation searches: μ- e- → e- e- in a muonic atom
Masafumi Koike1, Yoshitaka Kuno, Joe Sato
1Physics Department, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, Saitama 338-8570, Japan. koike@krishna.th.phy.saitama-u.ac.jp
Physical Review Letters
|September 28, 2010
Summary
We propose a new process in muonic atoms to search for charged lepton flavor violation. This method enhances the detection rate, offering complementary insights into fundamental physics beyond the Standard Model.
Area of Science:
- Particle Physics
- Atomic Physics
- Beyond Standard Model Physics
Background:
- Charged Lepton Flavor Violation (CLFV) is a key indicator of new physics.
- Existing searches for CLFV processes like muon-to-electron conversion have set stringent limits.
- Muonic atoms offer a unique environment to probe new physics due to enhanced interaction rates.
Purpose of the Study:
- To propose and analyze a novel CLFV process: mu- e- → e- e- within a muonic atom.
- To investigate the potential for enhanced event rates due to nuclear Coulomb attraction.
- To estimate the sensitivity of this process using current experimental constraints.
Main Methods:
- Theoretical analysis of the μ- e- → e- e- process in muonic atoms.
- Calculation of the branching ratio enhancement factor compared to μ+ e- → e+ e-.
- Estimation of upper limits on the branching ratio based on existing experimental data.
Main Results:
- The Coulomb attraction in heavy muonic atoms significantly enhances the rate of μ- e- → e- e- compared to μ+ e- → e+ e-.
- Estimated upper limits for the branching ratio are in the O(10^-17) to O(10^-18) range for photonic and four-fermion interactions.
- The proposed process provides a complementary search channel for CLFV.
Conclusions:
- The μ- e- → e- e- process in muonic atoms is a promising channel for discovering new physics beyond the Standard Model.
- This search complements existing CLFV experiments and can provide unique insights into the nature of lepton flavor violation.
- Further experimental efforts targeting this process could significantly advance our understanding of fundamental particle interactions.
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