The Search for ${\mu }^{+}\to e^{+}\gamma$ with 10${}^{-14}$ Sensitivity: the Upgrade of the MEG Experiment

Abstract

The MEG experiment took data at the Paul Scherrer Institute in the years 2009--2013 to test the violation of the lepton flavour conservation law, which originates from an accidental symmetry that the Standard Model of elementary particle physics has, and published the most stringent limit on the charged lepton flavour violating decay ${\mu }^{+}\to {\mathrm{e}}^{+}\gamma$: BR(${\mu }^{+}\to {\mathrm{e}}^{+}\gamma$) $<4.2\times 10^{-13}$ at 90% confidence level. The MEG detector has been upgraded in order to reach a sensitivity of $6\times 10^{-14}$. The basic principle of MEG II is to achieve the highest possible sensitivity using the full muon beam intensity at the Paul Scherrer Institute ($7\times 10^7$ muons/s) with an upgraded detector. The main improvements are better rate capability of all sub-detectors and improved resolutions while keeping the same detector concept. In this paper, we present the current status of the preparation, integration and commissioning of the MEG II detector in the recent engineering runs.

12 pages, 4 figures. The version of acceptance for Symmetry

References in corpus (4)

• Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm
• Technical design of the phase I Mu3e experiment
• The MEG detector for $\mu +\to e+\gamma$ decay search
• A photogrammetric method for target monitoring inside the MEG II detector

Cited by in corpus (21)

• Predictions from scoto-seesaw with $A_4$ modular symmetry
• Introduction to Charged Lepton Flavour Violation
• Leptoflavorgenesis: baryon asymmetry of the Universe from lepton flavor violation
• Next-to-leading order scalar contributions to $\mu \to e$ conversion
• High-precision muon decay predictions for ALP searches
• Dynamical scoto-seesaw mechanism with gauged $B-L$
• PeV-scale leptogenesis, gravity waves and black holes from a SUSY-breaking phase transition
• A Comparative Study of Z${}^{\prime }$ mediated Charged Lepton Flavor Violation at future lepton colliders
• Scotoseesaw model implied by dark right-handed neutrinos
• Dark matter as the source of neutrino mass: theory overview and experimental prospects
• Flavour anomalies meet flavour symmetry
• Explaining the $\mathcal{R}(D)$ and $\mathcal{R}(D^{\ast })$ Anomalies in the $B-L$ Supersymmetric Standard Model with Inverse Seesaw
• Lower bounds on lepton flavor violating branching ratios in a radiative seesaw model
• Characterization of external cross-talk from silicon photomultipliers in a liquid xenon detector
• Search for R-Parity-Violation-Induced Charged Lepton Flavor Violation at Future Lepton Colliders
• Lepton Flavor Violation and Local Lepton Number
• Muon to positron conversion
• Revisiting Neutrino Masses In Clockwork Models
• Type-III Scotogenic Model: Inflation, Dark Matter and Collider Phenomenology
• Riding the Seesaw: What Higgsstrahlung May Reveal about Massive Neutrinos
• Predictions for ${\Lambda }_b\to {\Lambda }_c\tau \bar{\nu }$ in BLSSM with Inverse seesaw