اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurements of the $Upsilon(10860)$ and $Upsilon(11020)$ resonances via $sigma(e^+e^-rightarrowUpsilon(n{rm S})pi^+pi^-)$
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We report new measurements of the total cross sections for $e^+e^-to Upsilon(n{rm S})pi^+pi^-$ ($n$ = 1, 2, 3) and $e^+e^-to bbar b$ from a high-luminosity fine scan of the region $sqrt{s} = 10.63$-$11.05$ GeV with the Belle detector. We observe that the $Upsilon(n{rm S})pi^+pi^-$ spectra have little or no non-resonant component and extract from them the masses and widths of $Upsilon(10860)$ and $Upsilon(11020)$ and their relative phase. We find $M_{10860}=(10891.1pm3.2^{+0.6}_{-1.7})$ MeV/$c^2$ and $Gamma_{10860}=(53.7^{+7.1}_{-5.6},^{+1.3}_{-5.4})$ MeV and report first measurements $M_{11020}=(10987.5^{+6.4}_{-2.5},^{+9.0}_{-2.1})$ MeV/$c^2$, $Gamma_{11020}=(61^{+9}_{-19},^{+2}_{-20})$ MeV, and $phi_{rm 11020}-phi_{rm 10860} = (-1.0pm0.4,^{+1.4}_{-0.1})$ rad.
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