Observation of the Heavy Baryons Sigma b and Sigma b*.

We report an observation of new bottom baryons produced in pp collisions at the Tevatron. Using 1.1 fb(-1) of data collected by the CDF II detector, we observe four Lambda b 0 pi+/- resonances in the fully reconstructed decay mode Lambda b 0-->Lambda c + pi-, where Lambda c+-->pK* pi+....

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Bibliografiske detaljer
Main Authors: Aaltonen, T, Abulencia, A, Adelman, J, Affolder, T, Akimoto, T, Albrow, MG, Amerio, S, Amidei, D, Anastassov, A, Anikeev, K, Annovi, A, Antos, J, Aoki, M, Apollinari, G, Arisawa, T, Artikov, A, Ashmanskas, W, Attal, A, Aurisano, A, Azfar, F, Azzi-Bacchetta, P, Azzurri, P, Bacchetta, N, Badgett, W, Barbaro-Galtieri, A
Format: Journal article
Sprog:English
Udgivet: 2007
Beskrivelse
Summary:We report an observation of new bottom baryons produced in pp collisions at the Tevatron. Using 1.1 fb(-1) of data collected by the CDF II detector, we observe four Lambda b 0 pi+/- resonances in the fully reconstructed decay mode Lambda b 0-->Lambda c + pi-, where Lambda c+-->pK* pi+. We interpret these states as the Sigma b(*)+/- baryons and measure the following masses: m Sigma b+=5807.8 -2.2 +2.0(stat.)+/-1.7(syst.) MeV/c2, m Sigma b- =5815.2+/-1.0(stat.)+/-1.7(syst.) MeV/c2, and m(Sigma b*)-m(Sigma b)=21.2-1.9 +2.0(stat.)-0.3+0.4(syst.) MeV/c2.