Measurement of the Branching Fractions for Psi(2S) --] E+e- and Psi(2S)--]mu+mu-

Download or read book Measurement of the Branching Fractions for Psi(2S) --] E+e- and Psi(2S)--]mu+mu- written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors measure the branching fractions of the [psi](2S) meson to the leptonic final states e[sup +]e[sup -] and [mu][sup +][mu][sup -] relative to that for [psi](2S) [yields] J/[psi] [pi][sup +][pi][sup -]. The method uses [psi](2S) mesons produced in the decay of B mesons at the [Upsilon](4S) resonance in a data sample collected with the BABAR detector at the Stanford Linear Accelerator Center. Using previous measurements for the [psi](2S) [yields] J/[psi] [pi][sup +][pi][sup -] branching fraction, they determine the e[sup +]e[sup -] and [mu][sup +][mu][sup -] branching fractions to be 0.0078 [+-] 0.0009 [+-] 0.0008 and 0.0067 [+-] 0.0008 [+-] 0.0007 respectively.