New limits on heavy sterile neutrino mixing in B-8 decay obtained with the Borexino detector

作者：Bellini G^*; Benziger J; Bick D; Bonfini G; Bravo D; Avanzini M Buizza; Caccianiga B; Cadonati L; Calaprice F; Cavalcante P; Chavarria A; Chepurnov A; D' Angelo D; Davini S; Derbin A; Drachnev I; Empl A; Etenko A; Fomenko K; Franco D; Galbiati C; Gazzana S; Ghiano C; Giammarchi M; Goeger Neff M; Goretti A; Grandi L; Hagner C; Hungerford E; Ianni Aldo; Ianni Andrea; Kobychev V; Korablev D; Korga G; Kryn D; Laubenstein M

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2013, 88(7): 072010.

DOI：10.1103/PhysRevD.88.072010

If heavy neutrinos with mass m(vH) %26gt;= 2m(e) are produced in the Sun via the decay B-8 -%26gt; Be-8 + e(+) + v(H) in a side branch of the pp chain, they would undergo the observable decay into an electron, a positron and a light neutrino v(H) -%26gt; v(L) + e(+) + e(-). In the present work Borexino data are used to set a bound on the existence of such decays. We constrain the mixing of a heavy neutrino with mass 1: 5 MeV %26lt;= m(vH) %26lt;= 14 MeV to be vertical bar U-eH vertical bar(2) %26lt;= (10(-3) - 4 x 10(-6) ), respectively. These are tighter limits on the mixing parameters than obtained in previous experiments at nuclear reactors and accelerators.

• 出版日期2013-10-29
• 单位中国地震局