https://doi.org/10.1140/epja/i2009-10891-5
Regular Article - Experimental Physics
The study of the negative pion production in neutron-proton collisions at beam momenta below 1.8 GeV/c
1
Petersburg Nuclear Physics Institute, 188300, Gatchina, Russia
2
Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Bonn, Germany
* e-mail: nikonov@hiskp.uni-bonn.de
Received:
12
June
2009
Revised:
18
September
2009
Accepted:
15
October
2009
Published online:
10
November
2009
A detailed investigation of the reaction np
pp
has been carried out using the data obtained with the continuous neutron beam produced by charge exchange scattering of protons off the deuterium target. Partial-wave event-by-event analysis based on the maximum likelihood method was applied to determine contributions of different partial waves to the pion production process. A combined analysis of the np
pp
and pp
pp
data measured in the same energy region allows us to determine the contribution of isoscalar partial waves (I = 0 in the momentum range from 1.1 up to 1.8GeV/c . The decay of isoscalar partial waves into the (1
S
0)pp
channel provides us with a good tool for the determination of the pp
S -wave scalar scattering length in the final state which was found to be a
pp = - 7.5±0.3 fm.
© SIF, Springer-Verlag Berlin Heidelberg, 2010
