The design of the MEG II experiment

Baldini, A.; Baracchini, E.; Bemporad, C.; Berg, F.; Biasotti, M.; Boca, G.; Cattaneo, P. W.; Cavoto, G.; Cei, F.; Chiappini, M.; Chiarello, G.; Chiri, C.; Cocciolo, G.; Corvaglia, A.; Bari, A. de; Gerone, M. De; D’onofrio, A.; Francesconi, M.; Fujii, Y.; Galli, L.; Gatti, F.; Grancagnolo, F.; Grassi, M.; Grigoriev, D.N.; Hildebrandt, M.; Hodge, Z.; Ieki, K.; Ignatov, F.V.; Iwai, R.; Iwamoto, Toshiyuki; Kaneko, Daisuke; Kasami, K.; Kettle, P.‐R.; Khazin, B. I.; Khomutov, N. V.; Korenchenko, A. S.; Kravchuk, N. P.; Libeiro, T.; Maki, M.; Matsuzawa, N.; Mihara, S.; Milgie, Michael; Molzon, W.; Mori, T.; Morsani, F.; Mtchedilishvili, A.; Nakao, M.; Nakaura, S.; Nicoló, D.; Nishiguchi, H.; Nishimura, M.; Ogawa, S.; Ootani, Wataru; Panareo, M.; Papa, A.; Pepino, A.; Piredda, G.; Popov, A.; Raffaelli, F.; Renga, F.; Ripiccini, E.; Ritt, Stefan Andreas; Rossella, M.; Rutar, G.; Sawada, R.; Signorelli, G.; Simonetta, M.; Tassielli, G.; Uchiyama, Y.; Usami, M.; Venturini, M.; Voena, C.; Yoshida, Keisuke; Yudin, Yu.V.; Zhang, Y.

doi:10.1140/epjc/s10052-018-5845-6

Cited by 273 publications

(243 citation statements)

References 117 publications

(160 reference statements)

Supporting

Mentioning

230

Contrasting

Unclassified

Order By: Relevance

“…In Fig. 7 we show our predictions for the maximum possible rates for several LFV τ decays consistent with current bounds from µ → eγ and µ − e (Ti), the indirect limits (61) and perturbative unitarity (60).…”

Section: B τ − E Transitionssupporting

confidence: 75%

“…To answer this question we have con- (61), for two values of the neutrino mass-ratio r. The predictions for µ → eeē and µ − e (Ti) get constrained to the corresponding bands whose upper (lower) boundaries are determined by sν τ = 0 (s max ντ ). Higher masses are forbidden by perturbative unitarity (60) for these mixings. The ratio of BR(Z → µe) to current limits is always much smaller than the others, below 10 −6 .…”

Section: Numerical Resultsmentioning

confidence: 99%

“…The sensitivity to these transitions will be considerably improved in near-future experiments. The MEG-II and Mu3e experiments will reach branching ratios of order 6×10 −14 [60] and 10 −16 [61] for µ → eγ and µ → eeē, respectively, whereas the expected bounds from PRISM and COMET will be near 10 −18 [62] for µ−e (Ti) conversion and 10 −17 [66] for µ − e (Al). For the third family, the bounds on the τ → γ and τ → ¯ branching ratios could be improved by two orders of magnitude at Belle-II when the experiment achieves its maximum luminosity [63,67].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Effects of heavy Majorana neutrinos on lepton flavor violating processes

et al. 2020

View full text Add to dashboard Cite

The observation of lepton flavor violating processes at colliders could be a clear signal of a nonminimal neutrino sector. We define a 5-parameter model with a pair of TeV fermion singlets and arbitrary mixings with the three active neutrino flavors. Then we analyze several flavor violating transitions ( → γ, ¯ or µ − e conversions in nuclei) and Z →¯ decays induced by the presence of heavy neutrinos. In particular, we calculate all the one-loop contributions to these processes and present their analytic expressions. We focus on the genuine effects of the heavy Majorana masses, comparing the results in that case with the ones obtained when the two heavy neutrinos define a Dirac field. Finally, we use our results to update the bounds on the heavy-light mixings in the neutrino sector.

show abstract

Section: B τ − E Transitionssupporting

confidence: 75%

Section: Numerical Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of heavy Majorana neutrinos on lepton flavor violating processes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…We see that especially for µ → eγ there are many best fit points close to the current upper limit. This limit will be significantly improved to < 6 × 10 −14 by the upcoming MEG II experiment [113]. Similarly an improvement on the upper limit of BR(τ → µγ) by up to two orders of magnitude is expected from Belle II [114].…”

Section: Charged Lepton Flavor Violationmentioning

confidence: 91%

Complete vectorlike fourth family with U(1)′ : A global analysis

2020

View full text Add to dashboard Cite

In this paper we present an in-depth analysis of a recently proposed Standard Model extension with a complete fourth generation of quarks and leptons, which are vector-like with respect to the Standard Model gauge group and charged under a new spontaneously broken vector-like U(1) gauge symmetry. The model is designed to explain the known muon anomalies, i.e. the observed deviations from Standard Model predictions in the anomalous magnetic moment of the muon, ∆a µ , and in b → s + − processes. We perform a global χ 2 analysis of the data with 65 model parameters and including 98 observables. We find many points with χ 2 per degree of freedom ≤ 1. The vector-like leptons and the new heavy Z are typically much lighter than a TeV and would, thus, be eminently visible at the HL-LHC.

show abstract

“…Future prospects are looking to improve on this by an order of magnitude. Specifically, the MEG-II experiment [65,66] is predicted to start searching for µ → eγ decays this year, with a target sensitivity of 4 × 10 −14 .…”

Section: µ → Eγmentioning

confidence: 99%

Radiative neutrino mass model from a mass dimension-11 ∆L = 2 effective operator

Gargalionis

Popa-Mateiu

Volkas

2020

J. High Energ. Phys.

View full text Add to dashboard Cite

We present the first detailed phenomenological analysis of a radiative Majorana neutrino mass model constructed from opening up a ∆L = 2 mass-dimension-11 effective operator constructed out of standard model fields. While three such operators are generated, only one dominates neutrino mass generation, namely O 47 = L C LQ C QQQ C HH, where L denotes lepton doublet, Q quark doublet and H Higgs doublet. The underlying renormalisable theory contains the scalars S 1 ∼ (3, 1, 1/3) coupling as a diquark, S 3 ∼ (3, 3, 1/3) coupling as a leptoquark, and Φ 3 ∼ (3, 3, 2/3), which has no Yukawa couplings but does couple to S 1 and S 3 in addition to the gauge fields. Neutrino masses and mixings are generated at two-loop order. A feature of this model that is different from many other radiative models is the lack of proportionality to any quark and charged-lepton masses of the neutrino mass matrix. One consequence is that the scale of new physics can be as high as 10 7 TeV, despite the operator having a high mass dimension. This raises the prospect that ∆L = 2 effective operators at even higher mass dimensions may, when opened up, produce phenomenologically-viable radiative neutrino mass models. The parameter space of the model is explored through benchmark slices that are subject to experimental constraints from charged lepton flavour-violating decays, rare meson decays and neutral-meson mixing. The acceptable parameter space can accommodate the anomalies in R K ( * ) and the anomalous magnetic moment of the muon.

show abstract

The design of the MEG II experiment

Cited by 273 publications

References 117 publications

Effects of heavy Majorana neutrinos on lepton flavor violating processes

Effects of heavy Majorana neutrinos on lepton flavor violating processes

Complete vectorlike fourth family with U(1)′ : A global analysis

Radiative neutrino mass model from a mass dimension-11 ∆L = 2 effective operator

Contact Info

Product

Resources

About