English

Lepton flavor violating $\mu\to e\gamma$ and $\mu-e$ conversion in unparticle physics

High Energy Physics - Phenomenology 2008-11-28 v3

Abstract

We have studied lepton flavor violation processes μeγ\mu\to e\gamma and μe\mu-e conversion in nuclei induced by unparticle. Both Br(μeγ){\rm Br}(\mu\to e\gamma) and μe\mu-e conversion rate CR(μe,Nuclei){\rm CR}(\mu-e,{\rm Nuclei}) strongly depend on the scale dimension dUd_{\cal U} and the unparticle coupling λKff\lambda^{ff'}_{\rm K}(K=V, A, S, P). Present experimental upper bounds on Br(μeγ){\rm Br}(\mu\to e\gamma), CR(μe,Ti){\rm CR}(\mu-e,{\rm Ti}) and CR(μe,Au){\rm CR}(\mu-e,{\rm Au}) put stringent constraints on the parameters of unaprticle physics. The scale dimensions dUd_{\cal U} around 2 are favored for the unparticle scale ΛU\Lambda_{\cal U} of O(10TeV){\cal O}(10 {\rm TeV}) and the unparticle coupling of O(103){\cal O}(10^{-3}). CR(μe,Nuclei){\rm CR}(\mu-e,{\rm Nuclei}) is proportional to Zeff4A2/Z\rm{Z^4_{eff}A^2/Z} for the pure vector and scalar couplings between unparticle and SM fermions, this peculiar atomatic number dependence can be used to distinguish unparticle from other theoretical models.

Keywords

Cite

@article{arxiv.0709.3435,
  title  = {Lepton flavor violating $\mu\to e\gamma$ and $\mu-e$ conversion in unparticle physics},
  author = {Gui-Jun Ding and Mu-Lin Yan},
  journal= {arXiv preprint arXiv:0709.3435},
  year   = {2008}
}

Comments

16 pages, 5 figures

R2 v1 2026-06-21T09:20:07.855Z