Deuterium Z-pinches are e cient sources of pulsed soft and hard x-rays, fast ions,
and neutrons. Many phenomena related to an acceleration of ions and neutron
production on the Z-pinches have not yet been explained. Detailed understanding of
these phenomena could be multidisciplinary important. Therefore, these phenomena
are investigated in joint Czech-Russian experiments on the terawatt class GIT-12
device with the generator output voltage of 600 kV and current at stagnation of
about 3 MA. These experiments are interesting since by using the novel experimental
load composed of the deuterium gas-pu with outer plasma shell, the neutron yields
were signi cantly increased from the order of 1011 to the order of 1012. Such relatively
high neutron yields were earlier observed on the devices with signi cantly higher
current as the Saturn generator with the pulsed current of about 10 MA. At the
same time, in our experiments, hydrogen ions with an energy above 38 MeV were
detected. Such results are unique in experiments on the generator with the abovementioned
maximum current and voltage.
The work reported in this thesis is focused on the diagnostics of Z-pinch plasma
by neutron detectors and interpretation of the experimental results. The precise
neutron diagnostics is in our experiments necessary because the produced neutron
pulses carry the information about the deuterons which produced them. In this
thesis, the extensive neutron detection system is presented. This system is based
on several principally independent methods: neutron bubble detectors, scintillation
neutron time-of-
ight diagnostics, neutron activation diagnostics with the moderator
(silver activation counter), and fast neutron activation diagnostics with various
energy threshold. This diagnostic system was used to evaluate neutron yields, energy
spectrum, and neutron
uences at di erent distances and directions. The in
uence
of non-dd neutrons on the experimental results is discussed.
cze
dc.language.iso
en
en
dc.title
High Energy Density Plasma Diagnostics Using Neutron and Gamma Detectors
en
dc.type
disertační práce
cze
dc.description.department
Katedra fyziky
theses.degree.discipline
Fyzika plazmatu
theses.degree.grantor
České vysoké učení technické v Praze. Fakulta elektrotechnická. Katedra fyziky