Measurement of the Decay K[sub L] [r arrow] [pi][sup 0][gamma][gamma]

Journal Article · Sun Aug 01 04:00:00 EDT 1999 · Physical Review Letters

OSTI ID:6272042

Cheu, E; Taegar, S A; Wang, J ^[1]; Arisaka, K; Jennings, J; Slater, W; Tripathi, A ^[2]; Kobrak, H G; Swanson, R A ^[3]; Blucher, E; Bown, C; Bright, S; Graham, G; Graham, J; Kessler, R; Monnier, E; Prasad, V; Qiao, C; Quinn, B; Roodman, A ; Shawhan, P S; Solomey, N; Swallow, E C; Wah, Y W; Winstein, B; Winston, R; Zimmerman, E D ^[4]; Barker, A R; LaDue, J; Mikelsons, P; Nauenberg, U; Toale, P A; Wu, J ^[5]; Swallow, E C ^[6]; Bellantoni, L; Ben-David, R; Bock, G J; Childress, S; Coleman, R; Crisler, M B; Ford, R; Hs,

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1. University of Arizona, Tucson, Arizona 85721 (United States)
2. University of California at Los Angeles, Los Angeles, California 90095 (United States)
3. University of California at San Diego, La Jolla, California 92093 (United States)
4. The Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637 (United States)
5. University of Colorado, Boulder, Colorado 80309 (United States)
6. Elmhurst College, Elmhurst, Illinois 60126 (United States)

We report on a new measurement of the decay K[sub L][r arrow][pi][sup 0][gamma][gamma] by the KTeV experiment at Fermilab. We determine the K[sub L][r arrow][pi][sup 0][gamma][gamma] branching ratio to be (1.68[plus minus]0.07[plus minus]0.08)[times]10[sup [minus]6] . Our data show the first evidence for a low-mass [gamma][gamma] signal as predicted by recent O(p[sup 6]) chiral perturbation calculations which include vector meson exchange contributions. From our data, we extract a value for the effective vector coupling a[sub V]=[minus]0.72[plus minus]0.05[plus minus]0.06 . [copyright] [ital 1999] [ital The American Physical Society ]

• OSTI ID: 6272042
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Vol. 83:5; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

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