Study of 3NF effects via few-nucleon scattering

Experimentally, one must utirize systems with more than two nucleons($A\ge 3$) to investigate properties of 3NFs. We have performed the measurement of all deuteron analyzing powers for {\it dp} elastic scattering at $250-300$ MeV/nucleon. Serious discrepancies are found between the data and the Faddeev calculations at very backward angles($\theta_{{\rm c.m.}}\ge 120^{\circ}$), which are not explained even taking into account 3NFs. These results indicate some significant dynamical components, e.g. short-range 3NFs, are missing in the calculations. In order to extend the study of 3NF to many-nucleon system we are planning the measurements of {\it p}$+^3$He scattering.