Limit on the production of a light vector gauge boson in phi meson decays with the KLOE detector

作者：Babusci D; Badoni D; Balwierz Pytko I; Bencivenni G; Bini C; Bloise C; Bossi F; Branchini P; Budano A; Balkestahl L Caldeira; Capon G; Ceradini F; Ciambrone P; Czerwinski E; Dane E; De Lucia E; De Robertis G; De Santis A; Di Domenico A; Di Donato C; Di Salvo R; Domenici D; Erriquez O; Fanizzi G; Fantini A; Felici G; Fiore S; Franzini P; Gauzzi P; Giardina G; Giovannella S^*; Gonnella F; Graziani E; Happacher F; Heijkenskjold L

来源：Physics Letters B, 2013, 720(1-3): 111-115.

DOI：10.1016/j.physletb.2013.01.067

• e( )e(-) Collisions
• Dark forces
• Gauge vector boson

We present a new limit on the production of a light dark-force mediator with the KLOE detector at DA Phi NE. This boson, called U, has been searched for in the decay phi -%26gt; eta U, U -%26gt; e(+)e(-), analyzing the. decay eta -%26gt; pi(0)pi(0)pi(0) in a data sample of 1.7 fb(-1). No structures are observed in the e(+)e(-) invariant mass distribution over the background. This search is combined with a previous result obtained from the decay eta -%26gt; pi(+)pi(-)pi(0), increasing the sensitivity. We set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of alpha%26apos;/alpha %26lt; 1.7 x 10(-5) for 30 %26lt; M-U %26lt; 400 MeV and alpha%26apos;/alpha %26lt;= 8 x 10(-6) for the sub-region 50 %26lt; M-U %26lt;210 MeV. This result assumes the Vector Meson Dominance expectations for the phi eta gamma* transition form factor. The dependence of this limit on the transition form factor has also been studied.

• 出版日期2013-3-13