Bubak, A. (Corresponding author)FZJ*

2004
Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag Jülich

Report No.: Juel-4138

Abstract: The emission of the intermediate mass fragments (IMFs; 2 $\le$ Z $\le$ 14) produced in the interaction of 1 .9 GeV protons with nickel ($^{nat}$Ni) has been a subject of interest of the present study. Energy spectra of isotopically and elementally identified ejectiles have been measured at angles 15° and 120° with the respect to the beam direction. The identification of the emitted IMFs has been performed by means of the Bragg curve spectroscopy and the time-of-flight technique (TOF). The Bragg curve detectors (BCDs) were employed for the charge identification, whereas the TOF method combined with the BCD, for the mass identification. The main task of the present PhD thesis was to built appropriate data acquisition system, to perform the experiment on the internal beam of the COSY accelerator, to propose the methodology of the off-line analysis of the data, to apply it to the event-by-event stored data, and to perform the phenomenological analysis of the obtained data. The results, experimental procedures, and different techniques of the element and isotope identification by means of the BCD + TOF are presented. The determination of the power law parameter $\tau$ characterizing the mass and charge distributions of the reaction products is discussed. Various methods of the nuclear matter temperature determination, the comparison between nuclear matter thermometers, and the discussion of the obtained results, shown in the energy-temperature diagram (the so called caloric curve), are presented as well. The results suggest two different mechanisms of the IMFs production : from the equilibrated (IMFs measured at 120°), and non-equilibrated (IMFs measured at 15°) state of the nucleus.

Keyword(s): emission

1. Experimentelle Hadronstruktur (IKP-1)