Author/Authors :
Zhang، نويسنده , , S. and Lin، نويسنده , , W. and Rodrigues، نويسنده , , M.R.D. and Huang، نويسنده , , M. and Wada، نويسنده , , R. and Liu، نويسنده , , X. and Zhao، نويسنده , , M. and Jin، نويسنده , , Z. and Chen، نويسنده , , Z. and Keutgen، نويسنده , , T. and Kowalski، نويسنده , , S. and Hagel، نويسنده , , K. and Barbui، نويسنده , , M. and Bonasera، نويسنده , , A. and Bottosso، نويسنده , , C. and Materna-Morris، نويسنده , , T. and Natowitz، نويسنده , , J.B. and، نويسنده ,
Abstract :
The neutron detection efficiency of a DEMON detector, averaged over the whole volume, was calculated using GEANT and applied to determine neutron multiplicities in an intermediate heavy ion reaction. When a neutron source is set at a distance of about 1 m from the front surface of the detector, the average efficiency, ϵ av , is found to be significantly lower (20–30%) than the efficiency measured at the center of the detector, ϵ 0 . In the GEANT simulation the ratio R = ϵ av / ϵ 0 was calculated as a function of neutron energy. The experimental central efficiency multiplied by R was then used to determine the average efficiency. The results were applied to a study of the 64Zn+112Sn reaction at 40 A MeV which employed 16 DEMON detectors. The neutron multiplicity was extracted using a moving source fit. The derived multiplicities are compared well with those determined using the neutron ball in the NIMROD detector array in a separate experiment. Both are in good agreement with multiplicities predicted by a transport model calculation using an antisymmetric molecular dynamics (AMD) model code.
