  Understanding of the exact nature of three-nucleon forces is the most
challenging topic in the field of nuclear physics. Three-nucleon break-up
reaction is a good tool to look into the underlying dynamics of the nuclear
force, thanks to its rich kinematical phase space which has different levels of
sensitivity to three-nucleon force effects. The recent studies on few-nucleon
systems have revealed that the current nuclear force models cannot describe
nucleon-deuteron scattering data accurately. In the present work, the analyzing
powers of the proton-deuteron break-up reaction obtained using a 190 MeV
polarized proton beam will be discussed. We present for the first time the
vector analyzing powers for the kinematics in which one of the protons scatters
to intermediate and large scattering angles at this energy. The results show a
fairly good agreement with various theoretical predictions for both
intermediate and large scattering angles of the break-up phase space.
