Two Ways of High-Energy Heavy Ion Interactions: Spallation and Burst

Reinhard Brandt¹, Valery Ditlov², Maria Haiduc³, Elena Firu³, Alina Tania Neagu³, Eberhard Ganssauge⁴, Reza Hashemi-Nezhad⁵, Wolfram Westmeier^6*

¹Kernchemie, FB Chemie, Philipps-Universitat Marburg, Marburg, Germany.
²Alikhanov Institute of Theoretical and Experimental Physics, Moscow, Russia.
³Bucharest Institute of Space Sciences, Bucharest, Romania.
⁴Fachbereich Physik, Philipps-Universitat Marburg, Marburg, Germany.
⁵School of Physics, University of Sydney, Sydney, Australia.
⁶Dr. Westmeier GmbH, Ebsdorfergrund, Germany.

DOI: 10.4236/wjnst.2015.52007                

Abstract

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 ¹²C and 72 GeV ⁴⁰Ar irradiations. Interactions of 72 GeV ²²Ne 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.

Keywords

Thick Target, High Energy Projectile, Unresolved Problems, BURST

Conflicts of Interest

The authors declare no conflicts of interest.

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