Vol. 29, issue 02, article # 2

Abstract:

Spectral and amplitude-temporal characteristics of plasma of a pulse-periodic nanosecond discharge initiated by runaway electrons in nitrogen in a pressure range 30–760 torr are investigated. Voltage pulses (U = 13 kV, FWHM is 10 ns, front duration is 4 ns, negative polarity, f = 60 Hz) applied to a cathode made of aluminum. The cathode had a cone form. Diameter of cone base, apex angle, and corner radius of cone apex were 6 mm, 30°, and 0.2 mm, respectively. A flat anode was located at distances of 2 and 6 mm from the cathode apex. Waveforms of voltage pulses, discharge current, radiation intensity, and spectra of discharge plasma were registered. At an interelectrode distance of 2 mm, colored jets of metal vapor were observed near the cathode apex throughout the pressure range. Size of jets was about 1 mm. Intense lines of atoms (Al I) and ions (Al II) of aluminum with wavelengths of 394.4; 396.15 nm and 622.62; 623.17; 704.21; 705.66; 706.36 nm were registered, respectively. Luminescence duration (> 2 ms) of the both was larger than the discharge current duration (~ 1 ms).

Keywords:

nanosecond pulse-periodic discharge, nitrogen, non-uniform electric field distribution, aluminum, metal vapor jets, colored mini jets

References:

1. Low temperature plasma technology: Methods and applications / Ed. by Paul K. Chu, Xin Pei Lu. Boca Raton, London, New York: CRC Press. Taylor & Francis Group, 2014. 493 p.
2. Low Temperature Plasma. Fundamentals, Technologies, and Techniques (2nd ed.) / Ed. by R. Hippler, H. Kersten, M. Schmidt, K.H. Schoenbach. Weinheim: Wiley, 2008. 945 p.
3. Packan D.М. Repetitive nanosecond glow discharge in atmospheric pressure air. Stanford: Stanford University, 2003. 164 p.
4. Runaway Electrons Preionized Diffuse Discharges / Ed. by V.F. Tarasenko. New York: Nova Science Publishers, Inc., 2014. 598 p.
5. Pai D.Z., Lacoste D.A., Laux C.O. Nanosecond repetitively pulsed discharges in air at atmospheric pressure – the spark regime // Plasma Sources Sci. Techn. 2010. V. 19, N 6. 065015.
6. Shao T., Tarasenko V.F., Zhang C., Baksht E.Kh., Yan P., Shut’ko Y. Repetitive nanosecond-pulse discharge in a highly nonuniform electric field in atmospheric air: X-ray emission and runaway electron generation // Laser Part. Beams. 2012. V. 30, N 3. P. 369–379.
7. Tarasenko V.F., Beloplotov D.V., Lomaev M.I., Sorokin D.A. O nabljudenii v laboratornyh razrjadah, iniciiruemyh puchkom ubegajushhih jelektronov, mini-sprajtov i golubyh mini-struj // Optika atmosf. i okeana. 2014. V. 27, N 11. P. 1017–1019.
8. Beloplotov D.V., Lomaev M.I., Sorokin D.A., Tarasenko V.F. Mini sprites and mini blue jets in nanosecond diffuse discharge in high-pressure nitrogen // Dev. Applicat. Ocean. Eng. 2014. V. 3. P. 63–68.
9. Beloplotov D.V., Lomaev M.I., Tarasenko V.F. O prirode izluchenija golubyh i zelenyh struj v laboratornyh razrjadah, iniciiruemyh puchkom ubegajushhih jelektronov // Optika atmosf. i okeana. 2015. V. 28, N 4. P. 349–353; Beloplotov D.V., Lomaev M.I., Tarasenko V.F. On the nature of radiation of blue and green jets in laboratory discharges initiated by runaway electrons // Atmos. Ocean. Opt. 2015. V. 28, N 5. P. 476–480.
10. Beloplotov D.V., Lomaev M.I., Sorokin D.A., Tarasenko V.F. Blue and green jets in laboratory discharges initiated by runaway electrons // J. Phys.: Conf. Series. 2015. V. 652. 012012.
11. Bugaev S.P., Litvinov E.A., Mesjac G.A., Proskurovskij D.I. Vzryvnaja jemissija jelektronov // Uspehi fiz. nauk. 1975. V. 115, N 1. P. 101–120.
12. Kramida A., Ralchenko Yu., Reader J. NIST ASD Team (2014). NIST Atomic Spectra Database (ver. 5.2). URL: http://physics.nist.gov/asd (Аccessed November 9, 2015).
13. Tarasenko V.F. Jeffektivnost' azotnogo UF-lazera s nakachkoj samostojatel'nym razrjadom // Kvant. jelektron. 2001. V. 31, N 6. P. 489–494.