ECRIS2018 - List of Authors (Biri, S.)

Paper	Title	Page
TUP14	Multi-Diagnostic Setup to Investigate the Two-Close-Frequency Phenomena	115
	S. Biri, Z. Perduk, R. RÃ¡cz ATOMKI, Debrecen, Hungary C. Caliri, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, F.P. Romano, G. Torrisi INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy J. Pálinkás University Debrecen, Debrecen, Hungary F.P. Romano IBAM-CNR, Catania, Italy
	While the mechanism is still not clear, the beneficial effect (higher intensity of highly charged ions, stable plasma conditions) of the second microwave injected to the ECR plasma was observed in many laboratories, both with close and far frequencies. Due to the complexity of the phenomena (e.g. interaction of resonant zones, damped instabilities) complex diagnostic methods are demanded to understand its mechanism better and to fully exploit the potential hidden in it. It is a challenging task since complex diagnostics methods require the arsenal of diagnostic tools to be installed to a relatively small size plasma chamber. Effect of the injected second 13.6-14.6 GHz microwave to the 14.25 GHz basic plasma has been investigated by means of soft and (time-resolved) hard X-ray spectroscopy, by X-ray imaging and by probing the rf signals emitted by the plasma. In order to separate the source and position of different X-ray photons special metallic materials for the main parts of the plasma chamber were chosen. A detailed description and explanation of the full experimental setup and the applied non-invasive diagnostics tools and its roles are presented in this paper.
	Poster TUP14 [2.615 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-TUP14
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEA5	Effect of the Two-Close-Frequency Heating to the Extracted Ion Beam and to the X-Ray Flux Emitted by the ECR Plasma	165
	R. RÃ¡cz, S. Biri, Z. Perduk ATOMKI, Debrecen, Hungary G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, G. Torrisi INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy J. Pálinkás University Debrecen, Debrecen, Hungary
	Multiple frequency heating has been used since the '90 in ECR ion sources as heating schemes able to improve current intensities especially for highly charged ions. More recently, "Two Close Frequency Heating", where the frequency gap is comparable with the scale-length of the resonance, has been proposed, expected also to be sensitive to the relative waves phase relationship. At ATOMKI - Debrecen a dedicated experiment has been carried out for exploring the effects of the combined frequencies and their relative phase-difference in an argon plasma. The second frequency was finely tuned between 13.6-14.6 GHz with respect to the first one (fixed 14.25 GHz). An optimal frequency gap (in terms of Ar¹¹⁺/A⁶⁺ beam currents ratios) has been experimentally found, in agreement with the theory; the optimal power balance (total RF power was 200 W) between the two frequencies has been determined empirically. A weak but clear effect of the relative phase shift has been observed. Each configuration has been characterized by a multi-diagnostics set-up: HPGe and SDD detectors were used for the X-rays, a RF probe was introduced inside the plasma chamber to detect the radio-emission from the plasma.
	Slides WEA5 [4.394 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-WEA5
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FRB2	Impact of the Two Close Frequency Heating on ECRIS Plasmas Stability	214
	E. Naselli, C. Caliri, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, F.P. Romano, G. Torrisi INFN/LNS, Catania, Italy S. Biri, Z. Perduk, R. RÃ¡cz ATOMKI, Debrecen, Hungary A. Galatà INFN/LNL, Legnaro (PD), Italy E. Naselli Catania University, Catania, Italy J. Pálinkás DU, Debrecen, Hungary F.P. Romano IBAM-CNR, Catania, Italy
	Several experiments have recently demonstrated that plasma instabilities are powerful limiting factors to the flux of highly charged ion beam extracted from ECRIS. One of the methods for damping the instabilities is to feed the plasma in two frequency heating mode. Since the fundamental physical mechanism is still unclear (diffusion in velocity space? additional confinement?), a deeper experimental investigation is necessary, using multi-diagnostics setups. At ATOMKI-Debrecen the effect on the plasma instabilities of an argon plasma in a 'Two Close Frequencies' scheme has been explored. Spectra of radio-emission from the plasma have been collected for different frequency gaps and relative power balances. The measurements show the plasma self-emitted radiation comes out from the internal plasma (i.e. around the lower frequency) but the instability damping can be effective for some specific combinations of frequency-gap and power balance. Radiofrequency spectra have been collected simultaneously to time-resolved X-ray measurements, triggered by RF bursts produced by the instabilities and detected via a microwave diode connected to a plasma-chamber-immersed multi-pin RF probe.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-FRB2
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Multi-Diagnostic Setup to Investigate the Two-Close-Frequency Phenomena

115

S. Biri, Z. Perduk, R. RÃ¡cz
ATOMKI, Debrecen, Hungary
C. Caliri, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, F.P. Romano, G. Torrisi
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
J. Pálinkás
University Debrecen, Debrecen, Hungary
F.P. Romano
IBAM-CNR, Catania, Italy

While the mechanism is still not clear, the beneficial effect (higher intensity of highly charged ions, stable plasma conditions) of the second microwave injected to the ECR plasma was observed in many laboratories, both with close and far frequencies. Due to the complexity of the phenomena (e.g. interaction of resonant zones, damped instabilities) complex diagnostic methods are demanded to understand its mechanism better and to fully exploit the potential hidden in it. It is a challenging task since complex diagnostics methods require the arsenal of diagnostic tools to be installed to a relatively small size plasma chamber. Effect of the injected second 13.6-14.6 GHz microwave to the 14.25 GHz basic plasma has been investigated by means of soft and (time-resolved) hard X-ray spectroscopy, by X-ray imaging and by probing the rf signals emitted by the plasma. In order to separate the source and position of different X-ray photons special metallic materials for the main parts of the plasma chamber were chosen. A detailed description and explanation of the full experimental setup and the applied non-invasive diagnostics tools and its roles are presented in this paper.

Poster TUP14 [2.615 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-TUP14

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEA5

Effect of the Two-Close-Frequency Heating to the Extracted Ion Beam and to the X-Ray Flux Emitted by the ECR Plasma

165

R. RÃ¡cz, S. Biri, Z. Perduk
ATOMKI, Debrecen, Hungary
G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, G. Torrisi
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
J. Pálinkás
University Debrecen, Debrecen, Hungary

Multiple frequency heating has been used since the '90 in ECR ion sources as heating schemes able to improve current intensities especially for highly charged ions. More recently, "Two Close Frequency Heating", where the frequency gap is comparable with the scale-length of the resonance, has been proposed, expected also to be sensitive to the relative waves phase relationship. At ATOMKI - Debrecen a dedicated experiment has been carried out for exploring the effects of the combined frequencies and their relative phase-difference in an argon plasma. The second frequency was finely tuned between 13.6-14.6 GHz with respect to the first one (fixed 14.25 GHz). An optimal frequency gap (in terms of Ar¹¹⁺/A⁶⁺ beam currents ratios) has been experimentally found, in agreement with the theory; the optimal power balance (total RF power was 200 W) between the two frequencies has been determined empirically. A weak but clear effect of the relative phase shift has been observed. Each configuration has been characterized by a multi-diagnostics set-up: HPGe and SDD detectors were used for the X-rays, a RF probe was introduced inside the plasma chamber to detect the radio-emission from the plasma.

Slides WEA5 [4.394 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-WEA5

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRB2

Impact of the Two Close Frequency Heating on ECRIS Plasmas Stability

214

E. Naselli, C. Caliri, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, F.P. Romano, G. Torrisi
INFN/LNS, Catania, Italy
S. Biri, Z. Perduk, R. RÃ¡cz
ATOMKI, Debrecen, Hungary
A. Galatà
INFN/LNL, Legnaro (PD), Italy
E. Naselli
Catania University, Catania, Italy
J. Pálinkás
DU, Debrecen, Hungary
F.P. Romano
IBAM-CNR, Catania, Italy

Several experiments have recently demonstrated that plasma instabilities are powerful limiting factors to the flux of highly charged ion beam extracted from ECRIS. One of the methods for damping the instabilities is to feed the plasma in two frequency heating mode. Since the fundamental physical mechanism is still unclear (diffusion in velocity space? additional confinement?), a deeper experimental investigation is necessary, using multi-diagnostics setups. At ATOMKI-Debrecen the effect on the plasma instabilities of an argon plasma in a 'Two Close Frequencies' scheme has been explored. Spectra of radio-emission from the plasma have been collected for different frequency gaps and relative power balances. The measurements show the plasma self-emitted radiation comes out from the internal plasma (i.e. around the lower frequency) but the instability damping can be effective for some specific combinations of frequency-gap and power balance. Radiofrequency spectra have been collected simultaneously to time-resolved X-ray measurements, triggered by RF bursts produced by the instabilities and detected via a microwave diode connected to a plasma-chamber-immersed multi-pin RF probe.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2018-FRB2

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)