اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurements of the masses and widths of the $Sigma_{c}(2455)^{0/++}$ and $Sigma_{c}(2520)^{0/++}$ baryons
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We present measurements of the masses and decay widths of the baryonic states $Sigma_{c}(2455)^{0/++}$ and $Sigma_{c}(2520)^{0/++}$ using a data sample corresponding to an integrated luminosity of 711 fb$^{-1}$ collected with the Belle detector at the KEKB $e^{+}e^{-}$ asymmetric-energy collider operating at the $Upsilon(4S)$ resonance. We report the mass differences with respect to the $Lambda_{c}^{+}$ baryon $M(Sigma_{c}(2455)^{0})-M(Lambda_{c}^{+}) = 167.29pm0.01pm0.02$ MeV/$c^{2}$, $M(Sigma_{c}(2455)^{++})-M(Lambda_{c}^{+}) = 167.51pm0.01pm0.02$ MeV/$c^{2}$, $M(Sigma_{c}(2520)^{0})-M(Lambda_{c}^{+}) = 231.98pm0.11pm0.04$ MeV/$c^{2}$, $M(Sigma_{c}(2520)^{++})-M(Lambda_{c}^{+}) = 231.99pm0.10pm0.02$ MeV/$c^{2}$, and the decay widths $Gamma(Sigma_{c}(2455)^{0}) = 1.76pm0.04^{+0.09}_{-0.21}$ MeV/$c^{2}$, $Gamma(Sigma_{c}(2455)^{++}) = 1.84pm0.04^{+0.07}_{-0.20}$ MeV/$c^{2}$, $Gamma(Sigma_{c}(2520)^{0}) = 15.41pm0.41^{+0.20}_{-0.32}$ MeV/$c^{2}$, $Gamma(Sigma_{c}(2520)^{++}) = 14.77pm0.25^{+0.18}_{-0.30}$ MeV/$c^{2}$, where the first uncertainties are statistical and the second are systematic. The isospin mass splittings are measured to be $M(Sigma_{c}(2455)^{++})-M(Sigma_{c}(2455)^{0})=0.22pm0.01pm0.01$ MeV/$c^{2}$ and $M(Sigma_{c}(2520)^{++})-M(Sigma_{c}(2520)^{0})=0.01pm0.15pm0.03$ MeV/$c^{2}$. These results are the most precise to date.
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