Measurements of the rare decay K(L) --> e(+)e(-)e(+)e(-)

A Alavi-Harati; T Alexopoulos; M Arenton; K Arisaka; S Averitte; A R Barker; L Bellantoni; A Bellavance; J Belz; R Ben-David; D R Bergman; E Blucher; G J Bock; C Bown; S Bright; E Cheu; S Childress; R Coleman; M D Corcoran; G Corti; B Cox; M B Crisler; A R Erwin; R Ford; A Glazov; A Golossanov; G Graham; J Graham; K Hagan; E Halkiadakis; J Hamm; K Hanagaki; S Hidaka; Y B Hsiung; V Jejer; D A Jensen; R Kessler; H G Kobrak; J LaDue; A Lath; A Ledovskoy; P L McBride; P Mikelsons; E Monnier; T Nakaya; K S Nelson; H Nguyen; V O'Dell; M Pang; R Pordes; V Prasad; B Quinn; E J Ramberg; R E Ray; A Roodman; M Sadamoto; S Schnetzer; K Senyo; P Shanahan; P S Shawhan; J Shields; W Slater; N Solomey; S V Somalwar; R L Stone; E C Swallow; S A Taegar; R J Tesarek; G B Thomson; P A Toale; A Tripathi; R Tschirhart; S E Turner; Y W Wah; J Wang; H B White; J Whitmore; B Winstein; R Winston; T Yamanaka; E D Zimmerman; KTeV Collaboration

doi:10.1103/PhysRevLett.86.5425

Measurements of the rare decay K(L) --> e(+)e(-)e(+)e(-)

Phys Rev Lett. 2001 Jun 11;86(24):5425-9. doi: 10.1103/PhysRevLett.86.5425.

Authors

A Alavi-Harati¹, T Alexopoulos, M Arenton, K Arisaka, S Averitte, A R Barker, L Bellantoni, A Bellavance, J Belz, R Ben-David, D R Bergman, E Blucher, G J Bock, C Bown, S Bright, E Cheu, S Childress, R Coleman, M D Corcoran, G Corti, B Cox, M B Crisler, A R Erwin, R Ford, A Glazov, A Golossanov, G Graham, J Graham, K Hagan, E Halkiadakis, J Hamm, K Hanagaki, S Hidaka, Y B Hsiung, V Jejer, D A Jensen, R Kessler, H G Kobrak, J LaDue, A Lath, A Ledovskoy, P L McBride, P Mikelsons, E Monnier, T Nakaya, K S Nelson, H Nguyen, V O'Dell, M Pang, R Pordes, V Prasad, B Quinn, E J Ramberg, R E Ray, A Roodman, M Sadamoto, S Schnetzer, K Senyo, P Shanahan, P S Shawhan, J Shields, W Slater, N Solomey, S V Somalwar, R L Stone, E C Swallow, S A Taegar, R J Tesarek, G B Thomson, P A Toale, A Tripathi, R Tschirhart, S E Turner, Y W Wah, J Wang, H B White, J Whitmore, B Winstein, R Winston, T Yamanaka, E D Zimmerman; KTeV Collaboration

Affiliation

¹ University of Wisconsin, Madison, Wisconsin 53706, USA.

PMID: 11415267
DOI: 10.1103/PhysRevLett.86.5425

Abstract

We observe 441 K(L)-->e(+)e(-)e(+)e(-) candidate events with a background of 4.2 events and measure B(K(L)-->e(+)e(-)e(+)e(-)) = [3.72+/-0.18(stat)+/-0.23(syst)]x10(-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 beta(CP) = -0.23+/-0.09(stat)+/-0.02(syst) and gamma(CP) = -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.