A new approach to solving the observation of enhanced neutron production in high-energy heavy ion induced reactions in thick targets is presented. Two different reaction mechanisms in these interactions are considered: 1) Limited fragmentation of the projectile, called SPALLATION; 2) Complete nuclear fragmentation of the projectile fragment into individual relativistic hadrons only, referred to as "BURST". The abundance of this second path increases with the charge and energy of the projectile and may be responsible for enhanced neutron production observed with radiochemical methods in 44 GeV 12 C and 72 GeV 40 Ar irradiations. Interactions of 72 GeV 22 Ne in nuclear emulsions show that SPALLATION and BURST have strongly different interaction signatures, and also that the rate of BURSTS increases from (26 ± 3)% of all interactions in the 1 st generation to (78 ± 6)% in the 2 nd generation. Further experimental signatures of BURSTS will be described; however, no model based on physics concepts can be presented. This effect may have practical consequences for neutron safety considerations in the construction of advanced heavy ion accelerators.

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Aspects of BURSTS and Spallation reactions induced by high-energy heavy ions in thick targets (>10 cm thick) will be investigated: BURSTS are reviewed from a historical and phenomenological point-of-view. Details of interactions in nuclear emulsions will be compared for irradiations of 72 GeV 22 Ne-ions from Dubna with irradiations of 72 GeV 40 Ar-ions from Berkeley. Measured correlations in individual interactions between multiplicities of "minimum ionizing particles", n s , and "black prongs", n b , will be shown as "n s -vs.-n b " per event for BURSTS and separately for Spallation in interactions of 72 GeV 22 Ne-ions. Monte Carlo calculations, based on the MCNPX 2.7 code, have been carried out for 72 GeV 22 Ne interacting in nuclear emulsions: The correlation between n s and n b in Spallation reactions could be understood. However, "n s -vs.-n b " correlations from BURST-interactions could not be reproduced with this model for events with small numbers of heavy prongs n h ≤ 10. For large numbers of heavy prongs with n h > 10 one could find some agreement between experiments and calculations, however, not in all details. Further experimental and theoretical studies are necessary before one has a complete understanding of BURST interactions in high-energy heavy ion reactions.

The opening of a new IUPAC-project is highly appreciated. In the year 2009, the IUPAC had published an article "Discovery of the element with atomic number 112 (IUPAC Technical Report)" [1]* which contains a section on the work of the Marinov collaboration. It appears that this section is not always in agreement with conventional standards for scientific publications. This present comment focuses on these formal questions.