On the search for density isomers in interaction of relativistic12C nuclei with lead

A Pb target was bombarded with12C nuclei of an energy of 15 and 43 GeV. The target was periodically transported to the inside of the neutron multiplicity detector which allowed measuring time distributions for events of multiple emission of delayed neutrons. Abnormal neutron emitters have not been found. Upper limits of probabilities of their production were estimated for the half-life range 10–105 s and for different mean multiplicities of neutrons¯n. The values obtained are within the interval from 1.4·10−9 (for¯n=12)to 4·10−6(for¯n=2).