Search for the rare decays K_L→π⁰π⁰µ⁺µ⁻ and K_L→π⁰π⁰X⁰→ π⁰π⁰µ⁺µ⁻

Journal Article · Wed Nov 09 00:00:00 EST 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.107.201803· OSTI ID:1023526

Abouzaid, E. ^[1]; Arenton, M. ^[2]; Barker, A. R. ^[3]; Bellantoni, L. ^[4]; Blucher, E. ^[1]; Bock, G. J. ^[4]; Cheu, E. ^[5]; Coleman, R. ^[4]; Corcoran, M. D. ^[6]; Cox, B. ^[2]; Erwin, A. R. ^[7]

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1. Enrico Fermi Institute, Univ. of Chicago, IL (United States)
2. Univ. of Virginia, Charlottesville, VA (United States)
3. Univ. of Colorado, Boulder, CO (United States)
4. Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
5. Univ. of Arizona, Tucson, AZ (United States)
6. Rice Univ., Houston, TX (United States)
7. Univ. of Wisconsin, Madison, WI (United States)

The KTeV E799 experiment has conducted a search for the rare decays K_L→π⁰π⁰µ⁺µ^- and K_L→π⁰π⁰X⁰→ π⁰π⁰µ⁺µ^-, where the X⁰ is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c². We find no evidence for either decay. We obtain upper limits of Br(K_L→π⁰π⁰X⁰ →π⁰π⁰µ⁺µ^-) < 1.0 x 10^-10 and Br(K_L→ π⁰π⁰µ⁺µ^-) < 9.2 x 10^-11 at the 90% confidence level. This result rules out the pseudoscalar X⁰ as an explanation of the HyperCP result under the scenario that the d¯sX⁰ coupling is completely real.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Contributing Organization: KTeV
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 1023526
• Report Number(s): FERMILAB-PUB-11-224-PPD; arXiv:1105.4800; oai:inspirehep.net:901060; TRN: US1104577
• Journal Information: Physical Review Letters, Vol. 107, Issue 20; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSONS
DECAY
PSEUDOSCALARS
experiment-HEP