Measurements of fast electron beams and soft X-ray emission from plasma-focus experiments

• Autorzy: Surała W. , Sadowski M. J. , Kwiatkowski R. , Jakubowski L. , Żebrowski J.

Identyfikatory

DOI

10.1515/nuka-2016-0028

• Konferencja: PLASMA-2015 International Conference on Research and Applications of Plasmas (7-11 September 2015 ; Warsaw, Poland)
• Języki publikacji: EN

Abstrakty

EN

The paper reports results of the recent experimental studies of pulsed electron beams and soft X-rays in plasma-focus (PF) experiments carried out within a modifi ed PF-360U facility at the NCBJ, Poland. Particular attention was focused on time-resolved measurements of the fast electron beams by means of two different magnetic analyzers, which could record electrons of energy ranging from about 41 keV to about 715 keV in several (6 or 8) measuring channels. For discharges performed with the pure deuterium fi lling, many strong electron signals were recorded in all the measuring channels. Those signals were well correlated with the fi rst hard X-ray pulse detected by an external scintillation neutron-counter. In some of the analyzer channels, electron spikes (lasting about dozens of nanoseconds) and appearing in different instants after the current peculiarity (so-called current dip) were also recorded. For several discharges, fast ion beams, which were emitted along the z-axis and recorded with nuclear track detectors, were also investigated. Those measurements confi rmed a multibeam character of the ion emission. The time-integrated soft X-ray images, which were taken side-on by means of a pinhole camera and sensitive X-ray fi lms, showed the appearance of some fi lamentary structures and so-called hot spots. The application of small amounts of admixtures of different heavy noble gases, i.e. of argon (4.8% volumetric), krypton (1.6% volumetric), or xenon (0.8% volumetric), decreased intensity of the recorded electron beams, but increased intensity of the soft X-ray emission and showed more distinct and numerous hot spots. The recorded electron spikes have been explained as signals produced by quasi-mono-energetic microbeams emitted from tiny sources (probably plasma diodes), which can be formed near the observed hot spots.

Słowa kluczowe

EN

electron beams; X-ray emission; plasma focus; hot spots

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2016
• Tom: Vol. 61, No. 2
• Strony: 161--167
• Opis fizyczny: Bibliogr. 13 poz., rys.

Twórcy

autor

Surała W.

• National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock/Swierk, Poland, Tel.: [phone], Fax: [phone]

autor

Sadowski M. J.

• National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock/Swierk, Poland and Institute of Plasma Physics and Laser Microfusion (IPPLM), 23 Hery Str., 01-497 Warsaw, Poland

autor

Kwiatkowski R.

• National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock/Swierk, Poland, Tel.: [phone], Fax: [phone]

autor

Jakubowski L.

• National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock/Swierk, Poland, Tel.: [phone], Fax: [phone]

autor

Żebrowski J.

• National Centre for Nuclear Research (NCBJ), 7 Andrzeja Soltana Str., 05-400 Otwock/Swierk, Poland, Tel.: [phone], Fax: [phone]

Bibliografia

• 1. Sadowski, M., Herold, H., Schmidt, H., & Shakhatre, M. (1984). Filamentary structure of a pinch column in plasma focus discharges. Phys. Lett. A, 105, 117–123.
• 2. Bernard, A., Bruzzone, H., Choi, P., Chuaqui, H., Gribkov, V., Herrera, J., Hirano, K., Krejci, A., Lee, S., Luo, C., Mezzetti, F., Sadowski, M., Schmidt, H., Ware, K., Wong, C. S., & Zoita, V. (1998). Scientific status of plasma focus research. J. Moscow Phys. Soc., 8, 93–170.
• 3. Scholz, M., Sadowski, M., & Szydlowski, A. (1999). Studies of the x-ray emission from high-current discharges performed in PF-1000 facility at different operational conditions. J. Tech. Phys., 40(Suppl. 1), 113–116.
• 4. Jakubowski, L., & Sadowski, M. J. (2002). Hot-spots in plasma-focus discharges as intense sources of different radiation pulses. Brazil. J. Phys., 32, 187–192.
• 5. Skladnik-Sadowska, E., Baranowski, J., Sadowski, M., & Zebrowski, J. (2002). X-ray and corpuscular emission from different plasma discharges of axial symmetry. J. High Temp. Mat. Proc., 6, 23–34.
• 6. Zebrowski, J., Sadowski, M. J., & Jakubowski, L. (2004). Studies of electron beams and x-rays within different plasma-focus devices. Czech. J. Phys., 54(Suppl. C), C256–C263.
• 7. Zebrowski, J., Sadowski, M. J., Czaus, K., Paduch, M., & Tomaszewski, K. (2004). Peculiar features of plasma-focus discharges within PF-360 facility. Czech. J. Phys., 54, 643–659.
• 8. Scholz, M., Paduch, M., Tomaszewski, K., Stepniewski, W., Bienkowska, B., Ivanova-Stanik, I., Karpinski, L., Miklaszewski, R., Sadowski, M. J., Jakubowski, L., Skladnik-Sadowska, E., Szydlowski, A., Malinowska, A., Kubes, P., Kravarik, J., Barvir, P., Klir, D., Tsarenko, A., & Schmidt, H. (2006). Recent results of MJ plasma--focus experiment. AIP Conf. Proc., 808, 207–210.http://dx.doi.org/10.1063/1.2159354.
• 9. Sadowski, M. J., & Scholz, M. (2008). The main issues of research on dense magnetized plasmas in PF discharges. Plasma Sources Sci. Technol., 17, 024001.
• 10. Kubes, P., Klir, D., Kravarik, J., Rezac, K., Paduch, M., Pisarczyk, T., Scholz, M., Chodukowski, T., Bienkowska, B., Ivanova-Stanik, I., Karpinski, L., Sadowski, M. J., Tomaszewski, K., & Zielinska, E. (2012). Energy transformation in column of plasma-focus discharges with MA currents. IEEE Trans. Plasma Sci., 40(2), 481–486.
• 11. Nuclear Enterprises. (1980). Scintillation materials. Sighthill, Edinburgh, Scotland. Retrieved from http://www.hpicorg.com/downloads/Nuclear%20Enterprises%20Scintillation%20Materials%20-%201980.pdf.
• 12. Surala, W., Sadowski, M. J., Paduch, M., Zielinska, E., & Tomaszewski, K. (2015). Recent measurements of soft X-ray emission from the DPF-1000U facility. Nukleonika, 60(2), 303–308.
• 13. Sadowski, M. J., Paduch, M., Skladnik-Sadowska, E., Surala, W., Zaloga, D., Miklaszewski, R., Zielinska, E., & Tomaszewski, K. (2015). Soft x-ray studies of plasma-focus pinch structures in PF-1000U experiments. Plasma Sources Sci. Technol., 24, 055003.

Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę.