THE (K-, PI(-)) AND (PI(-HYPERNUCLEAR POLARIZATION(), K+) REACTIONS AND LAMBDA)

The theoretical studies of (K-, pi(-)) and (pi(+), K+) reactions on p- shell targets are presented in the DWIA framework with use of the elem entary spin-nonflip and spin-flip amplitudes. Calculations can explain the available experimental data of excitation functions and angular d istributions of the (K-, pi(-)) reactions at P-K-=800 MeV/c and the (p i(+), K+) reactions at P-pi+=1.04 GeV/c. Characteristic and distinguis hed features of the excitation functions and cross sections are exhibi ted. Especially it is demonstrated that the (K-, pi(-)) reactions at P -K-=1.1 GeV/c and 1.5 GeV/c can excite the unnatural parity states wit h comparable strength to the natural parity ones. Further interesting is that the (pi(+), K+) and (K-, pi(-)) reactions with similar to 1 Ge V/c incident beams can be shown to produce very large polarizations of the produced hypernuclear states. Taking the subsequent deexcitation processes of the excited states into account, we have evaluated the hy pernuclear polarization and Lambda-spin polarization of the ground sta te and/or the ground-doublet states at the hypernuclear weak-decay sta ge, which would play a role in the hypernuclear coincidence experiment .