CP violations in π±→ meson decay

Gorazd Cvetič, C. S. Kim, Jilberto Zamora-Saá

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

We study the pion decays with intermediate on-shell neutrinos N into two electrons and a muon, π±→ → e ±→N → e±→e ±→μν. We investigate the branching ratios Br±→= [Γ(π- → e-e-μ+ν) ±→ Γ(π+ → e+e+μ-ν)] /Γ(π- → all) and the CP asymmetry ratio for such decays, in the scenario with two different on-shell neutrinos. If N is Dirac, only the lepton number conserving (LC) decays contribute (LC: ν = νeor); if N is Majorana, both LC and lepton number violating (LV) decays contribute (LV: or ν = νμ). The results show that the CP asymmetry is in general very small, but increases and becomes ∼1 when the masses of the two intermediate neutrinos get closer to each other, i.e., when their mass difference becomes comparable with their decay width, . The observation of CP violation in pion decays would be consistent with the existence of the well-motivated νMSM model with two almost degenerate heavy neutrinos.

Original languageEnglish
Article number075004
JournalJournal of Physics G: Nuclear and Particle Physics
Volume41
Issue number7
DOIs
Publication statusPublished - 2014 Jul

Fingerprint

CP violation
mesons
leptons
decay
neutrinos
pions
asymmetry
MSM (semiconductors)
muons
electrons

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

Cite this

Cvetič, Gorazd ; Kim, C. S. ; Zamora-Saá, Jilberto. / CP violations in π±→ meson decay. In: Journal of Physics G: Nuclear and Particle Physics. 2014 ; Vol. 41, No. 7.
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CP violations in π±→ meson decay. / Cvetič, Gorazd; Kim, C. S.; Zamora-Saá, Jilberto.

In: Journal of Physics G: Nuclear and Particle Physics, Vol. 41, No. 7, 075004, 07.2014.

Research output: Contribution to journalArticle

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