Three-nucleon force and the A(y) puzzle in intermediate energy p--> + d and d--> + p elastic scattering
New vector analyzing-power data on p-->+d elastic scattering at E(p) = 150 and 190 MeV have been measured. These are presented together with existing data and with recent d-->+p vector and tensor analyzing power data at E(d) = 270 MeV. The strong negative extremum of both vector analyzing powers A(p)(y) and A(d)(y) at straight theta(c.m.) approximately 80 degrees -120 degrees is underestimated by Faddeev calculations using modern NN forces. Inclusion of the Tucson-Melbourne 3N force shifts the minima upwards, but with conflicting results for A(p)(y), and leading to a good description for A(d)(y). An A(p)(y) puzzle, previously thought to exist at energies E(N)</=30 MeV only, appears to exist also at intermediate energies.
Bieber
R
Kernfysisch Versneller Instituut, Zernikelaan 25, 9747 AA Groningen, The Netherlands.
Glockle
W
Golak
J
Harakeh
MN
Huber
D
Huisman
H
Kalantar-Nayestanaki
N
Kamada
H
Messchendorp
JG
Nogga
A
Sakai
H
Sakamoto
N
Seip
M
Volkerts
M
van Der Werf SY
Witala
H