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:365891

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; Hsiung, Y B; Jensen, D A; McBride, P L; Nakaya, T; Nguyen, H; O`Dell, V; Pang, M; Pordes, R; Ramberg, E J; Ray, R E; Shanahan, P; Tschirhart, R; White, H B; Whitmore, J ^[7]; Hanagaki, K; Hidaka, S; Sadamoto, M; Senyo, K; Suzuki, I; Yamanaka, T ^[8]; Bellavance, A; Corcoran, M D ^[9]; Albuquerque, I F; Averitte, S; Belz, J; Bergman, D R; Halkiadakis, E; Lath, A; Schnetzer, S; Somalwar, S V; Stone, R L; Tesarek, R J; Thomson, G B ^[10]; Arenton, M; Corti, G; Cox, B; Golossanov, A; Hagan, K; Jejer, V; Ledovskoy, A; McManus, A P; Nelson, K S ^[11]; Alavi-Harati, A; others, and

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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)
7. Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)
8. Osaka University, Toyonaka, Osaka 560 (Japan)
9. Rice University, Houston, Texas 77005 (United States)
10. Rutgers University, Piscataway, New Jersey 08855 (United States)
11. The Department of Physics and the Institute of Nuclear and Particle Physics, University of Virginia, Charlottesville, Virginia 22901 (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: 365891
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 5 Vol. 83; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BRANCHING RATIO
CHIRAL SYMMETRY
FERMILAB
KAONS
PERTURBATION THEORY
PHOTONS
PIONS NEUTRAL
VECTOR MESONS