Author/Authors :
Betigeri، نويسنده , , M.G. and Biswas، نويسنده , , P.K. and Budzanowski، نويسنده , , A. and Chatterjee، نويسنده , , A. and Jahn، نويسنده , , Md. Motiar R. and Guha، نويسنده , , S. and Hawranek، نويسنده , , P. and Jain، نويسنده , , B.K. and Jawale، نويسنده , , S.B. and Jha، نويسنده , , V. and Kilian، نويسنده , , K. and Kliczewski، نويسنده , , S. and Kirillov، نويسنده , , Da. and Kirillov، نويسنده , , Di. and Kolev، نويسنده , , D. and Kravcikova، نويسنده , , M. and Kutsarova، نويسنده , , T. and Lesiak، نويسنده , , Joseph M. and Lieb، نويسنده , , J. and Machner، نويسنده , , H. and Magiera، نويسنده , , A. and Maier، نويسنده , , R. and Martinska، نويسنده , , G. and Nedev، نويسنده , , S. and Piskunov، نويسنده , , N. and Prasuhn، نويسنده , , D. and Proti?، نويسنده , , D. and Ritman، نويسنده , , J. and von Rossen، نويسنده , , P. and Roy، نويسنده , , B.J. and Shukla، نويسنده , , P. and Sitnik، نويسنده , , I. and Siudak، نويسنده , , R. and Tsenov، نويسنده , , R. and Ulicny، نويسنده , , M. and Urban، نويسنده , , J. and Vankova، نويسنده , , G.، نويسنده ,
Abstract :
A large acceptance scintillator detector with wavelength shifting optical fibre readout has been designed and built to detect the decay particles of η -nucleus bound system (the so-called η -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 4 π is obtained in the present design of the detector. Monte Carlo phase space calculations performed to simulate the formation and decay of η -mesic nuclei suggest that its decay particles, the protons and pions are emitted with an opening angle of 150 ± 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 has performed satisfactorily well. The present article describes the detector design, simulation studies, construction details and test results.
