Charge-Changing Reactions of Secondary Fragments Produced in High-Energy Heavy-Ion Collisions

Unusual behavior of projectile fragments produced by the interactions of relativistic Ar ions with copper

“…The results from large counter experiments, which detect interactions via changes in the charge Z of projectile fragments with 8 ~ Z < Zprimary, gave no evidence for anomalous projectile behavior. These data [9,10] had much smaller statistical uncertainties than those obtained by visual methods; the results, however, apply only to projectile fragments whose interactions lead to ~Z ~ 1 (i.e. a charge change of at least one unit between an incident heavy ion and its secondary heavy projectile fragment) moving within a narrow forward cone of~ 3°.…”

“…However, the effect itself has not been definitely established experimentally [2][3][4][5][6][7][8][9][10][11][12]. A large number of different experiments have been presented at the 1984 GSI Heavy Ion Study and summarized by Heinrich et al [13].…”

On the anomalon interpretation of40Ar + Cu collisions at 0.9 and 1.8 A GeV

“…A detailed study of the problem has indicated with great confidence that the anomalons with such cross sections as those given by Friedlender et al [1][2][3][4][5] and by Jain et al [6] do not exist. Dersch et al [1] have explained their experimental results on inelastic 4~ + Cu collisions at 0.9 and 1.8 GeV per nucleon on the basis of the concept of anomalons and/or "as inconsistency with known nuclear physics".…”

Search for anomalous interaction mean free paths of charge, 2?Z?18 projectile fragments in emulsions exposed to 1.8 A GeV40Ar ions

“…Jain et al [6] indicated the absence of the anomalous component in Z = 2 PFs and suggested a possible threshold effect at an energy of 1 A GeV. In recent years, results from a large number of experiments using emulsions [-2-14], C6r6nkov detectors [15][16][17][18], plastic detectors [19 22], bubble chambers [2355], magnetic spectrometers [26] and radio chemical techniques [27] have been reported. The conclusion from these experiments, using various heavy ion beams in the energy interval 1.8~4.2 A GeV must be that the observation of the anomalous component cannot be treated as conclusive.…”

“…The conclusion from these experiments, using various heavy ion beams in the energy interval 1.8~4.2 A GeV must be that the observation of the anomalous component cannot be treated as conclusive. Recent experiments using emulsions [8], C6r6nkov-detector [15][16][17][18] and plastic detector [27] have contradicted the observation of anomalous mean free path and have stressed that both systematic and statistical effects may simulate the anomalon-effect.…”