Precision measurement of the Ξ0 mass and the branching ratios of the decays Ξ0 → Λγ and Ξ0 → ∑0γ

Author(s): Fanti, V; Lai, A; Marras, D; Musa, L; Nappi, A; Hay, B; Moore, KN; Moore, RW; Munday, DJ; Needham, MD; Parker, MA; White, TO; Wotton, SA; Barr, G; Blumer, H; Bocquet, G; Bremer, J; Ceccucci, A; Cogan, J; Cundy, D; Doble, N; Fischer, G; Funk, W; Gatignon, L; Gianoli, A; Gonidec, A; Govi, G; Grafstrom, P; Lacourt, A; Luitz, S; Marzulli, V; Matheys, JP; Norton, A; Palestini, S; Panzer-Steindel, B; Schinzel, D; Taureg, H; Velasco, M; Vossnack, O; Wahl, H; Wirrer, G; Gaponenko, A; Kekelidze, V; Madigojine, D; Mestvirishvili, A; Molokanova, N; Potrebenikov, Y; Tatishvili, G; Tkatchev, A; Zinchenko, A; Boyle, O; Knowles, IG; Martin, VJ; Parsons, H; Contalbrigo, M; Dalpiaz, P; Duclos, J; Formica, A; Frabetti, PL; Martini, M; Petrucci, F; Savrie, M; Bizzeti, A; Calvetti, M; Collazuol, G; Graziani, G; Iacopini, E; Lenti, M; Michetti, A; Talamonti, C; Becker, HG; Coward, D; Ebersberger, C; Fox, H; Kalter, A; Kleinknecht, K; Koch, U; Kopke, L; Renk, B; Scheidt, J; Schmidt, J; Schue, Y; Schonharting, V | Abstract: A new precision measurement of the Ξ0 mass has been performed at the NA48 experiment at the CERN SPS. The value obtained is [1314.82±0.06 (stat.) ±0.2 (syst.)] MeV/c2. The branching ratios of Xi;0 radiative decays have been measured as: Br(Ξ0 → Λγ) = [1.90 ± 0.34(stat.) ± 0.19(syst.)] · 10-3 and Br(Ξ0 → ∑0γ) = [3.14 ± 0.76(stat.) ± 0.32(syst.)] · 10-3.