[en] Consecutive short bombardment of thick biological specimens with proton beams demonstrated that the yield from oxygen decreases with increasing amounts of total deposited beam; those from carbon and sulfur appear not to be affected, while significant yield increase are observed with respect to the ß-ray yields of all the other investigated isotopic nuclear reactions. The yield alterations were investigated in freeze-dried plant and animal specimens as well as in targets prepared by air drying at several temperatures. Only in ashed specimens do the ß-ray yields remain constant as a function of increasing amounts of deposited beam. The yield alterations induced by the beam on non-ashed biological specimens depend on (I) the total dissipated beam charge, (II) energy of the beam, (III) chemical element, (IV) origin of the biological specimen, and (V) method of preparation of the target. The underlying mechanism and implications of the yield alterations in the elemental analysis of non-ashed biological specimens are investigated and discussed. (author)

[en] The competition between pn and d evaporation leading to production of the same residual nucleus has been calculated in the framework of the Hauser-Feshbach theory for nine heavy-ion-induced nuclear reactions, each at several bombarding energies, for target-projectile combinations resulting in compound nuclei 12≤A≤40. The observed very good agreement between the experimental and the statistically predicted relative cross sections for pn and d emission indicates that both these exit channels proceed via evaporation from a compound nucleus

[en] The competition between pn and d evaporation leading to production of the same residual nuclei has been measured for several heavy-ion induced nuclear reactions. γ rays were measured in coincidence with a ΔE-E telescope for 9 reactions, each at several bombarding energies, for target-projectile combinations resulting in compound nuclei 19 < A < 71. An association of the ratio sigma/sub pn/sigma/sub d/ with the maximum excitation energy available to the residual nucleus demonstrates a systematic trend, the significance and potential applications of which are investigated

[en] Since the competition between cluster and constituent multiparticle emission producing the same residual nucleus in a nuclear reaction depends on the mechanism of the reaction, the pn over d ratio in the ¹⁶O(⁶Li, pn/d) reaction, measured between 10 and 19 MeV, is used to identify its mechanism as a function of energy. (orig.)

[en] The competition between p2n, dn and t evaporation leading to production of the same residual nuclei has been measured for 6 heavy-ion-induced nuclear reactions, each at several bombarding energies, for target-projectile combinations resulting in compound nuclei 29 < A < 37. An association of the relative yields for p2n, dn and t emission with the maximum excitation energy available to the residual nucleus demonstrates a systematic trend, the significance and potential applications of which are investigated. The application of the competition method in the delineation of the mechanisms involved in the ⁷Li + ³⁰Si reaction demonstrates that in addition to the tritons, the competing multiparticle exit channels are as well induced by a non-statistical mechanism. (orig.)

[en] The competition between pn and d evaporation leading to production of the same residual nuclei has been measured for 9 heavy-ion induced nuclear reactions, each at several bombarding energies, for target-projectile combinations resulting in compound nuclei 19 <= A <= 71. An association of the ratio sigmasup(pn)/sigmasub(d) with the maximum excitation energy available to the residual nucleus demonstrates a systematic trend, the significance and potential applications of which are investigated. (orig.)

[en] The cross section competition ratio σ_pn/σ_d for the reaction ¹⁶O+¹²C has been measured over the energy region of the tree resonances 11.85 (8⁺), 12.79 (7^-) and 19.71 (14⁺) MeV. Minima of the ratio for the resonances 12.79 and 19.71 MeV have been observed, while no similar sign appears at 11.85 MeV. Hauser-Fesbach predictions are inadequate to describe these minima. (orig.)