Forward-backward Emission of Target Evaporated Fragments in Nucleus-emulsion Collisions at a few Hundred MeV/nucleon

The multiplicity distribution,multiplicity moment,scaled variance,entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 150 AMeV ⁴He-AgBr,290 AMeV ¹²C-AgBr,400 AMeV ¹²C-AgBr,400 AMeV ²⁰Ne-AgBr and 500 AMeV ⁵⁶Fe-AgBr interactions are investigated.It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution.The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q,and the second-order multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere.The scaled variance,a direct measure of multiplicity fluctuations,is close to one for all the interactions,which indicate a weak correlation among the target evaporated fragments.The entropy of target evaporated fragments emitted in forward and backward hemispheres are the same respectively for all of the interactions,within experimental errors.