KIEROWNIK ZADANIA: dr Jan Woźniak
WSPÓŁPRACA:
ZPE WFITJ AGH;
IFJ im. H.Niewodniczańskiego w Krakowie;
ZIBJ Dubna, Rosja;
Physics Institute, University of Fribourg, Szwajcaria
High Current Electronics Institute, Tomsk, Rosja;
Paul Scherrer Institute, Szwajcaria
FINANSOWANIE:
działalność statutowa, dotacja,
KBN do współpracy międzynarodowej,
grant Pełnomocnika PAA w ZIBJ Dubna,
środki instytucji współpracujących
OPIS PRAC.
Tematyka:
PUBLIKACJE 2007
Czasopisma:
Abstract. The measurement method and results measuring of the stopping power ratio of helium-3 and deuterium atoms for muons slowed down in the D/3He mixture are presented. Measurements were performed at four values of pure 3He gas target densities, φHe = 0.0337, 0.0355, 0.0359, 0.0363 (normalized to the liquid hydrogen density) and at a density 0.0585 of the D/3He mixture. The experiment was carried out at PSI muon beam μE4 with the momentum Pμ= 34.0 MeV/c. The measured value of the mean stopping ratio S^3He/D is 1.66 +- 0.04.
Abstract. The interaction of two colliding deuterium plasma flows propagating in opposite directions across the magnetic field and having opposite directions of the polarization fields has been experimentally studied. The plasma flows with densities up to 10(16) cm(-3) stop and a velocity of up to 2 x 10(7) stop cm/s were formed using discharges initiated in crossed E x H fields. Each discharge operated at an electric power of up to 300 mW and a discharge current up to 100 kA. The results of measurements of the equivalent capacitance of polarized plasma flows were used to estimate the transverse permittivity of plasma. The rate of depolarization in colliding flows was determined. The frequency and energy characteristics of a plasma LC circuit formed by colliding flows were estimated. The temporal modulation of plasma density in the flows was measured.
Abstract. The possibility of using a plasma accelerator based on a pulsed Hall ion source to study the characteristics of pd, dd, d3He, 3He, and4He reactions in the astrophysical energy range (2201312 keV) has been considered. The preliminary experimental data on measurement of the astrophysical S factor for the dd reaction (dd 2192 3He + n (2.5 MeV)) at average deuteron collision energies E col = 4.5 and 4.95 keV and the deuteron beam energy spread FWHM = 18% are reported. The found value of the S factor is in agreement with the results of the experiments carried out by us previously using linear plasma in the inverse Z-pinch configuration.
Abstract. The results of the investigations of two colliding deuterium plasma flows propagating in opposite directions across the magnetic field and having opposite directions of the polarization fields has been presented. The plasma flows with densities up to 1016 cm-3 stop and a velocity of up to 2·107 cm/s were formed using discharges initiated in crossed E x H fields. Each discharge operated at an electric power of up to 300 mW and a discharge current up to 100 kA. The rate of depolarization in colliding flows was determined. The frequency and energy characteristics of a plasma LC circuit formed by colliding flows were estimated. The temporal modulation of plasma density in the flows was measured. <
Abstract. We discuss the possibility of using a plasma accelerator based on a pulsed Hall ion source to study the characteristics of pd, dd, and d3He reactions in the astrophysical energy range (2 - 12 keV). The preliminary experimental data on measurement of the astrophysical S-factor for the dd reaction (dd ->3He + n (2.5 MeV)) at the deuteron collision energies from the range 4 - 12 keV and the deuteron beam energy spread FWHM = 18agreement with the results of the experiments carried out by us previously using linear plasma in the inverse Z-pinch configuration.
Konferencje:
Abstract.
Abstract. Stopping power ratio of helium-3 and deuterium atoms for muons slowed down in the D/3He mixture was measured using 34.0 MeV/c muon beam at PSI meson factory. Four 3He targets with different gas densities and one D/3He target with helium atomic comcentration c = 0.05 were used. We present the measurement method and the analysis of experimental data. The measured value of the mean stopping ratio SHe/D is 1.66 +- 0.04.
Abstract. The final results of the μCF kinetics experimental study in solid hydrogen-deuterium mixtures at temperature 3K are presented. The experiment E742 has been carried out on the meson facility TRIUMF (Canada). The simultaneous analysis of the measured time distributions of pdμ molecule allowed to extract the values of the μCF chain parameters in H-D mixture: the fusion partial rates for different nuclear spin states of the pdμ molecule and the pdμ molecule formation rate.
Abstract. Methods and results of the two independent cycles of experiments performed at the meson factory TRIUMF (Canada) and PSI (Switzerland) and aimed at studying the μ-atomic and μ-molecular processes are reviewed. Application of the time-of-flight method and the solid hydrogen isotope mixture targets (H-D and H-T) at temperature 3 K in the TRIUMF experiments allowed obtaining for the first time a number of very important parameters of the muonic processes occuring in these mixtures. In PSI experiment the rate of the nuclear fusion in dμ3He has been measured for the first time.
Abstract. Measuring the astrophysical S-factors and cross sections of the reactions between light nuclei (pd,dd,d3He, and d6Li) allows to resolve many questions existing both in astrophysics and in nuclear physics. Research of the given processes in the ultralow energy region is rather problematic since intesity of the beams of the accelerated particles produced by classical accelerators are extremely low ( 1012 - 1013 s-1), and cross sections of these nuclear reactions in the astrophysical energy region are extremely small (10-39 - 10-33 cm2). An impetus to the current intensive study of indicated reactions has become the possibility of for these purposes using pulsed high-current plasma accelerators. Plasma accelerators with the liner plasma formation in the direct and inverse Z-pinch configuration and with closed Hall current pulse ion source allowed to receive the quantitative information on the astrophysical S-factors and effective cross sections of the pd and dd reactions (pd->4He+γ;dd-> 3He+n) in the energy region 2 - 12 keV. The results obtained indicate that, on the one hand, the technique proposed by us is worthy and can be effectively used to study nuclear reactions in the astrophysical energy region and, on the other hand, can be considered as a basis of the nuclear-physics diagnostics of plasma processes.
Abstract. Using the plasma accelerator based on the pulse Hall ion source, the first measurements of the astrophysical S-factor of the d+d->3He+n reaction were performed for deuteron energies 9.1 and 9.9 keV. The observed values of the S-factor and effective cross sections σdd for dd reaction are in agreement with the results obtained by us earlier in the experiments at liner plasma accelerators (in configuration of both direct and inverse Z-pinch). The preliminary results have confirmed the fact that the proposed technique can be effective to study nuclear reactions between light nuclei in the astrophysical energy region.