Phys. Rev. Lett.
86,
5425–5429
(2001)
Measurements of the Rare Decay KL → e+e-e+e-
A. Alavi-Harati et al. (KTeV Collaboration)
Show All Authors/Affiliations
Hide All Authors/Affiliations
A. Alavi-Harati12, T. Alexopoulos12, M. Arenton11, K. Arisaka2, S. Averitte10, A. R. Barker5, L. Bellantoni7, A. Bellavance9, J. Belz10, R. Ben-David7, D. R. Bergman10, E. Blucher4, G. J. Bock7, C. Bown4, S. Bright4, E. Cheu1, S. Childress7, R. Coleman7, M. D. Corcoran9, G. Corti11, B. Cox11, M. B. Crisler7, A. R. Erwin12, R. Ford7, A. Glazov4, A. Golossanov11, G. Graham4, J. Graham4, K. Hagan11, E. Halkiadakis10,*, J. Hamm1, K. Hanagaki8, S. Hidaka8, Y. B. Hsiung7, V. Jejer11, D. A. Jensen7, R. Kessler4, H. G. E. Kobrak3, J. LaDue5, A. Lath10, A. Ledovskoy11, P. L. McBride7, P. Mikelsons5, E. Monnier4,†, T. Nakaya7, K. S. Nelson11, H. Nguyen7, V. O'Dell7, M. Pang7, R. Pordes7, V. Prasad4, B. Quinn4, E. J. Ramberg7, R. E. Ray7, A. Roodman4, M. Sadamoto8, S. Schnetzer10, K. Senyo8, P. Shanahan7, P. S. Shawhan4, J. Shields11, W. Slater2, N. Solomey4, S. V. Somalwar10, R. L. Stone10, E. C. Swallow4,6, S. A. Taegar1, R. J. Tesarek10, G. B. Thomson10, P. A. Toale5, A. Tripathi2, R. Tschirhart7, S. E. Turner2, Y. W. Wah4, J. Wang1, H. B. White7, J. Whitmore7, B. Winstein4, R. Winston4, T. Yamanaka8, and E. D. Zimmerman4 (KTeV Collaboration)
1University of Arizona, Tucson, Arizona 85721
2University of California at Los Angeles, Los Angeles, California 90095
3University of California at San Diego, La Jolla, California 92093
4The Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637
5University of Colorado, Boulder, Colorado 80309
6Elmhurst College, Elmhurst, Illinois 60126
7Fermi National Accelerator Laboratory, Batavia, Illinois 60510
8Osaka University, Toyonaka, Osaka 560-0043 Japan
9Rice University, Houston, Texas 77005
10Rutgers University, Piscataway, New Jersey 08854
11The Department of Physics and Institute of Nuclear and Particle Physics, University of Virginia, Charlottesville, Virginia 22901
12University of Wisconsin, Madison, Wisconsin 53706
Received 5 February 2001; published in the issue dated 11 June 2001
We observe 441 KL→e+e-e+e- candidate events with a background of 4.2 events and measure B(KL→e+e-e+e-) = [3.72±0.18(stat)±0.23(syst)]×10-8 in the KTeV/E799II experiment at Fermilab. Using the distribution of the angle between the planes of the e+e- pairs, we measure the CP parameters βCP = -0.23±0.09(stat)±0.02(syst) and γCP = -0.09±0.09(stat)±0.02(syst). We also present the first detailed study of the e+e- invariant mass spectrum in this decay mode.
© 2001 The American Physical Society
URL:
http://link.aps.org/doi/10.1103/PhysRevLett.86.5425
DOI:
10.1103/PhysRevLett.86.5425
PACS:
13.20.Eb, 11.30.Er, 13.40.Hq, 14.40.Aq
*To whom correspondence should be addressed.Electronic address: evah@fnal.gov †On leave from C.P.P. Marseille/C.N.R.S., Marseille, France.
|
|
