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A stack of annular detectors made of high purity germanium was used to measure simultaneously pd → 3 H π + and pd → 3 He π 0 differential cross sections at beam momenta of 750 MeV/c, 800 MeV/c, and 850 MeV/c over a large angular range. The extracted total cross sections for the pd → 3 He π 0 reactions bridge a gap between near threshold data and those in the resonance region. The ratio of the cross sections for the two reaction channels taken at the same η = p cm π /m π yields 2.11±0.08 indicating that a deviation from isospin symmetry is very small.

A large acceptance scintillator detector with wavelength shifting optical fibre readout has been designed and built to detect the decay particles of Z-nucleus bound system (the so-called Z-mesic nuclei), namely, protons and pions. The detector, named as ENSTAR detector, consists of 122 pieces of plastic scintillator of various shapes and sizes, which are arranged in a cylindrical geometry to provide particle identification, energy loss and coarse position information for these particles. A solid angle coverage of $95% of total 4p is obtained in the present design of the detector. Monte Carlo phase space calculations performed to simulate the formation and decay of Z-mesic nuclei suggest that its decay particles, the protons and pions are emitted with an opening angle of 150 AE 20 , and with energies in the range of 25-300 and 225-450 MeV, respectively. The detailed GEANT simulations show that $80 % of the decay particles (protons and pions) can be detected within ENSTAR. Several test measurements using alpha source, cosmic-ray muons, etc. have been carried out to study the response of ENSTAR scintillator pieces. The in-beam tests of fully assembled detector with proton beam of momentum 870 MeV=c from the Cooler synchrotron COSY have been performed. The test results show that the scintillator fibre design chosen for the detector ARTICLE IN PRESS www.elsevier.com/locate/nima 0168-9002/$ -see front matter r .in (V. Jha).has performed satisfactorily well. The present article describes the detector design, simulation studies, construction details and test results. r

Ground-state a-spectroscopic factors for ' Ne, '"Mg, and "Ca have been determined via the (d, 'Li) reaction at E"=80 MeV. The results are compared with theoretica1 shell-model predictions. Relative spectroscopic factors for the excited 2+ and 4+ states in "Ar are also presented. NU'C LEAP QEAC'$1QNS Ne 4~6 Mg(g 6 J I) 6Q~N e Ca(d Lj) 36Ar&q= 80 MeV, measured 0(&6L, , 6), finite-range DWBA calculations.