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تسجيل مستخدم جديدThe X(3872) tetraquarks in B and B_s decays
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We discuss how the latest data on X(3872) in B and B_s decays speak about its tetraquark nature. The established decay pattern, including the up to date observations by CMS, are explained by the mixing of two quasi-degenerate, unresolvable, neutral states. The same mechanism also explains isospin violations in X decays and strongly suggests that the lurking charged partners are required to have very small branching fractions in J/psi rho^pm, well below the current experimental limits. In addition, a new prediction on the decay into J/psi omega final states is attained. The newest experimental observations are found to give thrust to the simplest tetraquark picture and call for a definitive, in-depth study of final states with charged rho mesons.
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We report the first observation of $B^0 to X(3872) (K^{+}pi^{-})$ and evidence for $B^+ to X(3872) (K^{0}pi^{+})$. We measure the product of branching fractions for the former to be ${cal B}(B^0 to X(3872) (K^+ pi^-)) times {cal B}(X(3872) to J/psi p
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We present results on the X(3872), produced in $B^+ to X(3872) K^+$ and $B^0 to X(3872) K^0_S$ decays where $X(3872) to J/psi pi^+ pi^-$. We report the first statistically significant observation of $B^0 to X(3872) K^0_S$ and measure the ratio of bra
nching fractions to be $frac{{cal B}(B^0 to X(3872)K^0)} {{cal B}(B^+ to X(3872)K^+)} = 0.82 pm 0.22 pm 0.05$, consistent with unity. The mass difference between the X(3872) states produced in $B^+$ and $B^0$ decay is found to be $delta M equiv M_{XK^+} - M_{XK^0} = (+0.18 pm 0.89 pm 0.26)$ MeV/$c^2$, consistent with zero. In addition, we search for the X(3872) in the decay $B^0 to X(3872)K^+pi^-$, $X(3872) to J/psi pi^+ pi^-$. We measure ${cal B}(B^0 to X(3872) (K^+ pi^-)_{NR}) times {cal B}(X(3872) to J/psi pi^+ pi^-) = (8.1 pm 2.0 ^{+1.1}_{-1.4})times 10^{-6}$ and we set the 90% C.L. limit, ${cal B}(B^0 to X(3872)K^{*}(892)^0) times {cal B}(X(3872) to J/psi pi^+ pi^-) < 3.4 times 10^{-6}$. The analysis is based on a 605 fb$^{-1}$ data sample collected at the $Upsilon(4S)$ with the Belle detector at the KEKB collider.
We report a study of $Bto (J/psi gamma) K$ and $Bto (psi gamma)K$ decay modes using $772times 10^{6}$ $Bbar{B}$ events collected at the Upsilon(4S)$ resonance with the Belle detector at the KEKB energy-asymmetric $e^+ e^-$ collider. We observe $X(387
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In this work, we revisit the isospin violating decays of $X(3872)$ in a coupled-channel effective field theory. In the molecular scheme, the $X(3872)$ is interpreted as the bound state of $bar{D}^{*0}D^0/bar{D}^0D^{*0}$ and $D^{*-}D^+/D^-D^{*+}$ chan
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