# Search for CP violation in positronium decay.

@article{Yamazaki2010SearchFC, title={Search for CP violation in positronium decay.}, author={Tomohiro Yamazaki and Toshio Namba and Shoji Asai and Takeshi Kobayashi}, journal={Physical review letters}, year={2010}, volume={104 8}, pages={ 083401 } }

CP violation in the quark sector has been well established over the last decade, but has not been observed in the lepton sector. We search for CP violating decay processes in positronium, using the angular correlation of (S x k{1})(S x k{1}x k{2}), where S is the positronium spin and k{1}, k{2} are the directions of the positronium decay photons. To a sensitivity of 2.2x10{-3}, no CP violation has been found, which is at the level of the CP violation amplitude in the K meson. A 90% confidence…

## 31 Citations

Electromagnet Design and Geometric Considerations for a Positronium CP Violation Experiment

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Abstract In this paper, we present prospects for using the Jagiellonian positron emission tomograph (J-PET) detector to search for discrete symmetries violations in a purely leptonic system of the…

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This work concerned two experimental searches for the violation of fundamental discrete symmetries in physical systems originating from electron-positron interactions. The first study was a direct…

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The capability of this system to register three-photon annihilations with an unprecedented range of kinematical configurations and to measure the CPT-odd correlation between positronium spin and annihilation plane orientation with a precision improved by at least an order of magnitude are demonstrated.

Studies of discrete symmetries in a purely leptonic system using the Jagiellonian Positron Emission Tomograph

- Physics
- 2016

Discrete symmetries such as parity (P), charge-conjugation (C) and time reversal (T) are of fundamental importance in physics and cosmology. Breaking of charge conjugation symmetry (C) and its…

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Tests of discrete symmetries in positronium decays with the J-PET detector

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As a relatively simple and purely leptonic state positronium constitutes a unique system to study discrete symmetries with precision limited only by the effects due to the weak interaction and…

Status and prospects of discrete symmetries tests in positronium decays with the J-PET detector

- PhysicsINTERNATIONAL CONFERENCE ON SCIENCE AND APPLIED SCIENCE (ICSAS) 2019
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Positronium is a unique laboratory to study fundamental symmetries in the Standard Model, reflection in space (𝒫), reversal in time (𝒯), charge conjugation (𝒞) and their combinations. The…

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Charged lepton system symmetry under combined charge, parity, and time-reversal transformation (CPT) remains scarcely tested. Despite stringent quantum-electrodynamic limits, discrepancies in…

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We report on the recent results on CP, T and CPT tests in the neutral kaon sector obtained with the KLOE dataset. Search for the CP-violating decay $K_S \to 3\pi^0$ is described. We present also…