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Radiative Decays of the Upsilon(1S) to a Pair of Charged Hadrons

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 نشر من قبل Pamela Morehouse
 تاريخ النشر 2005
  مجال البحث
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Using data obtained with the CLEO~III detector, running at the Cornell Electron Storage Ring (CESR), we report on a new study of exclusive radiative Upsilon(1S) decays into the final states gamma pi^+ pi^-, gamma K^+ K^-, and gamma p pbar.. We present branching ratio measurements for the decay modes Upsilon(1S) to gamma f_2(1270), Upsilon(1S) to gamma f_2(1525), and Upsilon(1S) to gamma K^+K^-; helicity production ratios for f_2(1270) and f_2(1525); upper limits for the decay Upsilon(1S) to gamma f_J(2200), with f_J(2220) to pi^+ pi^-, K^+ K^-, p pbar; and an upper limit for the decay Upsilon(1S) to gamma X(1860), with X(1860) to gamma p pbar.



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