Single-and double-spinflip prob.meas, and new isoscalar spin excitations

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The deuteron has an intrinsic spin of 1. Therefore two spinflip probabilities, DELTAs_y=1,2, can be defined with respect to the scattering plane. The aims of this project are to search for an isoscalar spin giant resonance or to obtain information on the isoscalar effective interaction(Vsigma)which is poorly known, by measuring these single(S_1)- and double(S_2)-spinflip probabilities.The spinflip probability for the deuteron scattering can be deduced by the vector and tensor polarization measurements for the inelastically scattered deuterons, so called a double scattering method. However the difficulty to measure the tensor polarization prevented us to deduce the spinflip probability for long time. We have, for the first time, designed and constructed the Deuteron POLarimeter(DPOL)which is capable to measure the vector and tensor polarizations simultaneously.We had to establish the reaction or scattering which is adequate for the purpose of polarization analysis.Based on such results we improved the DPOL and subsequently measured the effective analyzing POWersof DPOL.Owing to the accelerator beam-time allocation, we, unfortunately, could not get the polarized deuteron beams as we had expected. And thus it took so long time to complete this project.Overcoming these difficulties we succeeded, for the first time, to measure the double scattering for the ^<12>C(d, d')^<12>C reaction at E^d=270 MeV for a wide excitation energy range, 3<E_x<25 MeV,and a scattering angle range, 2.5ﾟ <rheta_<lab><7.5ﾟ and to deduce the single-and double-spinflip probabilities.It is shown that the single-spinflip probability is indeed large for the spin excitations and the double-spinflip probability is almost zero as expected for the present target and excitation energy range.Thus we conclude that our primary goal has been achieved.