Search for a Light Pseudoscalar Particle in the Decay K{sub L}{sup 0}{yields}{pi}{sup 0}{pi}{sup 0}X

Journal Article · Fri Feb 06 00:00:00 EST 2009 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.102.051802· OSTI ID:21180176

Tung, Y C; Hsiung, Y B; Wu, M L; Chen, K F ^[1]; Ahn, J K; Lee, H S; Lee, S Y ^[2]; Akune, Y; Fujioka, Y; Ishibashi, S; Kobayashi, S; Ogata, R; Sugiyama, A; Suzuki, S; Tsukamoto, T ^[3]; Baranov, V; Kurilin, A S; Kuzmin, E; Moisseenko, A; Podolsky, S ^[4]

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1. Department of Physics, National Taiwan University, Taipei, Taiwan 10617 (China)
2. Department of Physics, Pusan National University, Busan, 609-735 (Korea, Republic of)
3. Department of Physics, Saga University, Saga, 840-8502 Japan (Japan)
4. Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna, Moscow Region, 141980 (Russian Federation)

We performed a search for a light pseudoscalar particle X in the decay K{sub L}{sup 0}{yields}{pi}{sup 0}{pi}{sup 0}X, X{yields}{gamma}{gamma} with the E391a detector at KEK. Such a particle with a mass of 214.3 MeV/c{sup 2} was suggested by the HyperCP experiment. We found no evidence for X and set an upper limit on the product branching ratio for K{sub L}{sup 0}{yields}{pi}{sup 0}{pi}{sup 0}X, X{yields}{gamma}{gamma} of 2.4x10{sup -7} at the 90% confidence level. Upper limits on the branching ratios in the mass region of X from 194.3 to 219.3 MeV/c{sup 2} are also presented.

• OSTI ID: 21180176
• Journal Information: Physical Review Letters, Vol. 102, Issue 5; Other Information: DOI: 10.1103/PhysRevLett.102.051802; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
• Country of Publication: United States
• Language: English

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