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A study of B->X(3872) K, with X(3872)->J/Psi pi+ pi-

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 نشر من قبل Philippe Grenier
 تاريخ النشر 2008
  مجال البحث
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We present measurements of the decays B+ -> X(3872) K+ and B0 -> X(3872) K0 with X(3872) -> Jpsi pi+ pi-. The data sample used, collected with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring, corresponds to 455 x 10^6 BBbar pairs. Branching fraction measurements of BF(B+ -> X(3872) K+) x BF(X(3872) -> Jpsi pi+ pi-) = (8.4 +/- 1.5 +/- 0.7) x 10^{-6} and BF(B0 -> X(3872) K0) x BF(X(3872) -> Jpsi pi+ pi- = (3.5 +/- 1.9 +/- 0.4) x 10^{-6} are obtained. We set an upper limit on the natural width of the X(3872) of Gamma < 3.3 MeV/c^2 at the 90% confidence level.

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56 - F.S. Navarra , M. Nielsen 2006
New spectroscopy from the B factories, the advent of CLEO-c and the BES upgrade renewed the interest in charmonia. Among the new measurements, the state X(3872) has received special attention due to its unexpected properties. Its structure has been s tudied with different theoretical approaches, most of them being able to reproduce the measured mass. A further test for the theoretical descriptions of the X(3872) is to explain its narrow decay width. In this work we address the decays $Xto J/psi pi^+pi^-pi^0$ and $Xto J/psi pi^+ pi^-$, using QCD sum rules with the hypothesis that $X$ is a four quark state.
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