Search for the rare decays K(L)→π0π0μ+μ- and K(L)→π0π0X0→π0π0μ+μ-

E Abouzaid; M Arenton; A R Barker; L Bellantoni; E Blucher; G J Bock; E Cheu; R Coleman; M D Corcoran; B Cox; A R Erwin; C O Escobar; A Glazov; A Golossanov; R A Gomes; P Gouffon; Y B Hsiung; D A Jensen; R Kessler; K Kotera; A Ledovskoy; P L McBride; E Monnier; H Nguyen; R Niclasen; D G Phillips 2nd; H Ping; E J Ramberg; R E Ray; M Ronquest; E Santos; W Slater; D Smith; N Solomey; E C Swallow; P A Toale; R Tschirhart; C Velissaris; Y W Wah; J Wang; H B White; J Whitmore; M J Wilking; R Winston; E T Worcester; M Worcester; T Yamanaka; E D Zimmerman; R F Zukanovich; KTeV Collaboration

doi:10.1103/PhysRevLett.107.201803

Search for the rare decays K(L)→π0π0μ+μ- and K(L)→π0π0X0→π0π0μ+μ-

Phys Rev Lett. 2011 Nov 11;107(20):201803. doi: 10.1103/PhysRevLett.107.201803. Epub 2011 Nov 9.

Affiliation

¹ The Enrico Fermi Institute, The University of Chicago, Illinois 60637, USA.

PMID: 22181724
DOI: 10.1103/PhysRevLett.107.201803

Abstract

The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)μ(+)μ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-)) < 1.0 × 10(-10) and Br(K(L)→π(0)π(0)μ(+)μ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.