[en] Preliminary data is given for the mean free path of projectilelike fragments, 2< Z<18, emitted in ₄₀Ar induced heavy ion reactions in nuclear emulsions at 1.8A GeV as well as in later generations of fragmentation chains. Only within a distance of one cm or less from the interaction point do we observe an enhanced collision frequency. If this observation is a signal of an anomalous fragmentation component this must have a very short mean free path or a lifetime less than 10^-₁₁s. Some suggestions are given for systematic or statistaical effects which could also possibly explain our results. (authors)

No abstract available

[en] An analysis of multiply-charged projectile fragments has been performed from the point of view of fragmentation characteristics using a statistics of 916 fragments comprising over 923 interactions of ¹⁴N in emulsion at 2.1 GeV per nucleon. The number of interacting nucleons has been investigated in the light of the prediction of the participant-spectator model. The momentum of projectile fragments has been measured directly. Gaussian distributions have been fitted to the projected distributions as well as momentum distributions for multiply-charged projectile fragments at various intervals of impact parameter and in different reaction channels. Relativistic Maxwell-Boltzmann distributions have been fitted to the emission angles of He fragments, emitted in the collision with varius targets, to investigate the emission characteristics of relativistic projectile fragments. (orig.)

[en] Results are presented from an investigation of the mean free path in nuclear emulsion of multiply charged fragments, produced by 1.8A-GeV argon nuclei. Charge identification of 6965 fragments with charges Z> or =2, producing 2192 secondary interactions, has been made. No dependence of the mean free path on the distance from the preceding collision is observed and thus our result is consistent with the nonexistence of anomalons

[en] Some characteristics of gamma production have been studied in nuclear emulsions subjected to a magnetic field of strength 180 KG during exposure to a π^- beam of momentum 50 GeV/c. The gammas are selected from a very narrow forward cone (theta sub(L) <= 10⁰) in the laboratory system. The energy of the gamma rays are measured by using magnetic bending property of tracks and also by the usual coordinate methods. The average energy carried off by gammas and the average values of the longitudinal and transverse components and their moments have been estimated. The gamma momentum spectrum has also been studied in the ππ and πN CM systems. The experimental results are fairly well explained in terms of isobar productions as well as diffraction dissociation processes. (author)

[en] An analysis of projectile helium fragments has been performed from the point of view of testing the factorization and limiting fragmentation hypothesis. An event-by-event examination of 923 interactions of ¹⁴N in emulsion at 2.1 GeV per nucleon has been made for target identification. Events with projectile fragments have been divided into various reaction channels according to the multiplicity of He nuclei. The multiplicity distribution, angular structure and other properties of the projectile He fragments have been investigated to see the dependence on different targets and target excitation. The properties of He fragments emitted from the projectile have been found to remain independent of target in peripheral collision processes. The target and projectile breakup properties have been analysed in terms of the collision geometry. Gaussian distributions have been fitted to the projected angular distribution data for He fragments at various intervals of impact parameter and in different reaction channels. The properties of emitted He nuclei exhibit characteristic features of factorization and limiting fragmentation. (orig.)

[en] Experimental results on π^--emulsion interactions at 340 GeV/c are presented. The dependence of R on the target mass is studied in the light of constituent quark models. A universal relation for the [Nsub(s)] dependence on [Nsub(ch)] and [νsub(A)] is obtained. Systematics of shower multiplicity distributions are also studied and a new scaling function for integral probability distributions of shower tracks is worked out. (orig.)

[en] ⁴⁰Ar-emulsion interactions are studied, to investigate the question of anomalons, in two G-5 emulsion stacks. In about 4600 primary interactions, projectile fragments of Z ≥ 2 for all generations have been followed until they interact or leave the stack. Afer careful estimation of charges of these fragments, variation of their mean free paths is studied as a function of distance from the preceding interaction. Generation effect, N_h dependence and production angle effect are investigated. In addition multi-chain events are analysed separately. Our results do not show anomalons at the 6% level and are consistent with non occurrence of anomalons. However, this experiment is not sensitive enough to rule out anomalons (with a mfp of the order of 2 to 3 cm) produced about 1% (or less). (orig.)