Comment on “ πNN Coupling from High Precision np Charge Exchange at 162 MeV ”
نویسندگان
چکیده
In this updated and expanded version of our delayed Comment we show that the np backward cross section, as presented by the Uppsala group[1], is seriously flawed (more than 25 sd.). The main reason is the incorrect normalization of the data. We also show that their extrapolation method, used to determine the charged πNN coupling constant, is a factor of about 10 less accurate than claimed by Ericson et al.. The large extrapolation error makes the determination of the coupling constant by the Uppsala group totally uninteresting.
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