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Register a new userPerformance of the neutron polarimeter NPOL3 for high resolution measurements
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We describe the neutron polarimeter NPOL3 for the measurement of polarization transfer observables $D_{ij}$ with a typical high resolution of $sim$300 keV at $T_n$ $simeq$ 200 MeV. The NPOL3 system consists of three planes of neutron detectors. The first two planes for neutron polarization analysis are made of 20 sets of one-dimensional position-sensitive plastic scintillation counters with a size of 100 cm $times$ 10 cm $times$ 5 cm, and they cover the area of 100 $times$ 100 $mathrm{cm}^2$. The last plane for detecting doubly scattered neutrons or recoiled protons is made of the two-dimensional position-sensitive liquid scintillation counter with a size of 100 cm $times$ 100 cm $times$ 10 cm. The effective analyzing powers $A_{y;mathrm{eff}}$ and double scattering efficiencies $epsilon_{mathrm{D.S.}}$ were measured by using the three kinds of polarized neutrons from the ${}^{2}{rm H}(vec{p},vec{n})pp$, ${}^{6}{rm Li}(vec{p},vec{n}){}^{6}{rm Be}(mathrm{g.s.})$, and ${}^{12}{rm C}(vec{p},vec{n}){}^{12}{rm N}(mathrm{g.s.})$ reactions at $T_p$ = 198 MeV. The performance of NPOL3 defined as $epsilon_{mathrm{D.S.}}(A_{y;mathrm{eff}})^2$ are similar to that of the Indiana Neutron POLarimeter (INPOL) by taking into account for the counter configuration difference between these two neutron polarimeters.
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