πNNCoupling from High PrecisionnpCharge Exchange at 162 MeV

Nucleon-nucleon elastic scattering analysis to 2.5 GeV

“…We excluded these data from the analysis in order to retain the same database (below 350 MeV) as was used in the Nijmegen analysis [68]. This also applies to a new set of np differential cross sections at 162 MeV and at backward angles which were measured at the Svedberg Facility at Uppsala [69].…”

Angle-dependent normalization of neutron-proton differential cross sections

“…However, some of the sets required also a slight change in the definition of outlier to make them acceptable. In this manner, several np data sets [8][9][10]6] …”

“…This implies that these data sets can, instead of discarding them, from now on be included in the np database. The salvation of these systematically-flawed data sets [6][7][8][9][10] is a major accomplishment of our adnorm method.…”

“…In recent publications [13][14][15][16] we pointed out that the Uppsala data at 162 MeV [8,9] contain unexplained large systematic errors. Also some other np differential cross section measurements appeared to have systematic errors similar (but not identical) to the Uppsala data; the Princeton [6] and Freiburg [7,10] data are prominent examples.…”

“…Some flaws, on the other hand, are so serious that their contribution to χ 2 dominates over the statistical contribution to the extent that the standard rules of statistics no longer apply. Consequently, such data sets [6][7][8][9][10] must be excluded from the databases used in PWA's. This is of course an unfortunate and undesirable situation, especially in view of the waste of investment and effort involved in these experiments.…”