اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدStudy of $K^0_S$ pair production in single-tag two-photon collisions
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We report a measurement of the cross section for $K^0_S$ pair production in single-tag two-photon collisions, $gamma^* gamma to K^0_S K^0_S$, for $Q^2$ up to 30 GeV$^2$, where $Q^2$ is the negative of the invariant mass squared of the tagged photon. The measurement covers the kinematic range 1.0 GeV < W < 2.6 GeV and $|cos theta^*| < 1.0$ for the total energy and kaon scattering angle, respectively, in the $gamma^* gamma$ center-of-mass system. These results are based on a data sample of 759 fb$^{-1}$ collected with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. For the first time, the transition form factor of the $f_2(1525)$ meson is measured separately for the helicity-0, -1, and -2 components and also compared with theoretical calculations. Finally, the partial decay widths of the $chi_{c0}$ and $chi_{c2}$ mesons are measured as a function of $Q^2$.
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We report a high-statistics measurement of the differential cross section of the process gamma gamma --> K^0_S K^0_S in the range 1.05 GeV <= W <= 4.00 GeV, where W is the center-of-mass energy of the colliding photons, using 972 fb^{-1} of data coll
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We report a measurement of the differential cross section of $pi^0$ pair production in single-tag two-photon collisions, $gamma^* gamma to pi^0 pi^0$, in $e^+ e^-$ scattering. The cross section is measured for $Q^2$ up to 30 GeV$^2$, where $Q^2$ is t
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The differential cross section of the process gamma gamma -> pi^0 pi^0 has been measured in the kinematical range 0.6 GeV < W < 4.0 GeV and |cos theta*|<0.8 in energy and pion scattering angle, respectively, in the gamma gamma center-of-mass system.
We find at least four resonant structures including a peak from f_0(980). In addition, there is evidence for chi_{c0} production. We also make a preliminary discussion of the angular dependence and cross section ratio to gamma gamma -> pi^+ pi^-.
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