Tests of CP and CPT symmetry with positronium

Journal Article · Fri Aug 08 04:00:00 EDT 2008 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2977856· OSTI ID:21152357

Namba, T; Kobayashi, T ^[1]; Nishihara, K; Yamazaki, T; Asai, S ^[2]

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1. ICEPP, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
2. Department of Physics, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

The 3{gamma} decay of spin-aligned triplet positronium can be used to test CP (C = charge conjugation, and P = parity operation) invariance in the lepton sector. The angular correlation (s-circumflex {center_dot}k-circumflex {sub 1})(s-circumflex {center_dot}k-circumflex {sub 1}xk-circumflex {sub 2}) is used for this test, where s is the positronium spin and |k{sub 1}|>|k{sub 2}|>|k{sub 3}| are the {gamma} momenta.We designed a new detector to test this symmetry at the 10{sup -3} level. This detector consists of a magnet, a {beta}{sup +} tagging and o-Ps creation system, {gamma}-ray detectors, and a turntable. The detector construction is almost finished and data acquisition will begin in this spring.With a similar detector, the CPT (T = time reversal) symmetry can be also tested. In this case, the angular correlation (s-circumflex {center_dot}k-circumflex {sub 1}xk-circumflex {sub 2}) is used. This test will be started after the CP test is finished.

• OSTI ID: 21152357
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1037; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR CORRELATION
CP INVARIANCE
CPT THEOREM
DECAY
ELECTRON-POSITRON INTERACTIONS
ENERGY-LEVEL TRANSITIONS
GAMMA DETECTION
MAGNETS
PHOTONS
POSITRONIUM
RADIATION DETECTORS
SPIN
SYMMETRY