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38 results on '"A. Braeuning-Demian"'

1. X-ray emission associated with radiative recombination for Pb$^{82+}$ ions at threshold energies

Author

Zhu, B., Gumberidze, A., Over, T., Weber, G., Andelkovic, Z., Bräuning-Demian, A., Chen, R., Dmytriiev, D., Forstner, O., Hahn, C., Herfurth, F., Herdrich, M. O., Hillenbrand, P. -M., Kalinin, A., Kröger, F. M., Lestinsky, M., Litvinov, Y. A., Menz, E. B., Middents, W., Morgenroth, T., Petridis, N., Pfäfflein, Ph., Sanjari, M. S., Sidhu, R. S., Spillmann, U., Schuch, R., Schippers, S., Trotsenko, S., Varga, L., Vorobyev, G., and Stöhlker, Th.

Subjects
Physics - Atomic Physics
Abstract

For bare lead ions, decelerated to the low beam energy of 10 MeV/u, the x-ray emission associated with radiative recombination (RR) at "cold collision" conditions has been studied at the electron cooler of CRYRING@ESR at GSI-Darmstadt. Utilizing dedicated x-ray detection chambers installed at 0{\deg} and 180{\deg} observation geometry, we observed for the very first time for stored ions the full x-ray emission spectrum associated with RR under electron cooling conditions. Most remarkably, no line distortion effects due to delayed emission are present in the well resolved spectra, spanning over a wide range of x-ray energies (from about 5 to 100 keV) which enable to identify fine-structure resolved Lyman, Balmer as well as Paschen x-ray lines along with the RR transitions into the K-, L and M-shell of the ions. To compare with theory, an elaborate theoretical model has been applied. By considering the relativistic atomic structure of Pb$^{81+}$, this model is based on a sophisticated computation of the initial population distribution via RR for all atomic levels up to Rydberg states with principal quantum number $n=$ 165 in combination with cascade calculations based on time-dependent rate equations. Within the statistical accuracy, the experimental x-ray line emission is in very good agreement with the results of the theoretical model applied. Most notably, this comparison sheds light on the contribution of prompt and delayed X-ray emission (up to 70 ns) to the observed X-ray spectra, originating in particular from Yrast transitions into inner shells.

Published
2022
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2. Towards experiments with highly charged ions at HESR

Author

Sánchez, Rodolfo, Braeuning-Demian, Angela, Glorius, Jan, Kalinin, Anton, Hagmann, Siegbert, Hillenbrand, Pierre-Michel, Litvinov, Yuri A., Köhler, Thomas, Petridis, Nikolaos, Sanjari, Shahab, Spillmann, Uwe, and Stöhlker, Thomas

Subjects
Physics - Atomic Physics
Abstract

The atomic physic collaboration SPARC is a part of the APPA pillar at the future Facility for Antiproton and Ion Research. It aims for atomic-physics research across virtually the full range of atomic matter. A research area of the atomic physics experiments is the study of the collision dynamics in strong electro-magnetic fields as well as the fundamental interactions between electrons and heavy nuclei at the HESR. Here we give a short overview about the central instruments for SPARC experiments at this storage ring., Comment: 4 pages, 1 figures

Published
2020

4. SPARC Collaboration: New Strategy for Storage Ring Physics at FAIR

Author

Stöhlker, Thomas, Litvinov, Yuri A., Bräuning-Demian, Angela, Lestinsky, Michael, Herfurth, Frank, Maier, Rudolf, Prasuhn, Dieter, Schuch, Reinhold, and Steck, Markus

Subjects
Physics - Accelerator Physics, Physics - Atomic Physics
Abstract

SPARC collaboration at FAIR pursues the worldwide unique research program by utilizing storage ring and trapping facilities for highly-charged heavy ions. The main focus is laid on the exploration of the physics at strong, ultra-short electromagnetic fields including the fundamental interactions between electrons and heavy nuclei as well as on the experiments at the border between nuclear and atomic physics. Very recently SPARC worked out a realization scheme for experiments with highly-charged heavy-ions at relativistic energies in the High-Energy Storage Ring HESR and at very low-energies at the CRYRING coupled to the present ESR. Both facilities provide unprecedented physics opportunities already at the very early stage of FAIR operation. The installation of CRYRING, dedicated Low-energy Storage Ring (LSR) for FLAIR, may even enable a much earlier realisation of the physics program of FLAIR with slow anti-protons., Comment: IX International Workshop on "APPLICATION OF LASERS AND STORAGE DEVICES IN ATOMIC NUCLEI RESEARCH", Recent Achievements and Future Prospects, May 13 - 16, 2013, Pozna\'n, Poland

Published
2014
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5. Electron gas polarization effect induced by heavy H-like ions of moderate velocities channeled in a silicon crystal

Author

Dauvergne, D., Bräuning-Demian, A., Bosch, F., Bräuning, H., Chevallier, M., Cohen, C., Gumberidze, A., Hagmann, S., L'hoir, A., Kirsch, R., Kozhuharov, C., Liesen, D., Mokler, P. H., Poizat, J. -C., Ray, C., Rozet, J. -P., Stöhlker, Th., Toleikis, S., Toulemonde, M., and Verma, P.

Subjects
Physics - Atomic Physics
Abstract

We report on the observation of a strong perturbation of the electron gas induced by 20 MeV/u U$^{91+}$ ions and 13 MeV/u Pb$^{81+}$ ions channeled in silicon crystals. This collective response (wake effect) in-duces a shift of the continuum energy level by more than 100 eV, which is observed by means of Radiative Electron Capture into the K and L-shells of the projectiles. We also observe an increase of the REC probability by 20-50% relative to the probability in a non-perturbed electron gas. The energy shift is in agreement with calculations using the linear response theory, whereas the local electron density enhancement is much smaller than predicted by the same model. This shows that, for the small values of the adiabaticity parameter achieved in our experiments, the density fluctuations are not strongly localized at the vicinity of the heavy ions.

Published
2005
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6. Impact parameter sensitive study of inner-shell atomic processes in the experimental storage ring

Author

Gumberidze, A., Kozhuharov, C., Zhang, R.T., Trotsenko, S., Kozhedub, Y.S., DuBois, R.D., Beyer, H.F., Blumenhagen, K.-H., Brandau, C., Bräuning-Demian, A., Chen, W., Forstner, O., Gao, B., Gassner, T., Grisenti, R.E., Hagmann, S., Hillenbrand, P.-M., Indelicato, P., Kumar, A., Lestinsky, M., Litvinov, Yu. A., Petridis, N., Schury, D., Spillmann, U., Trageser, C., Trassinelli, M., Tu, X., and Stöhlker, Th.

Published
2017
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7. APPA at FAIR: From fundamental to applied research

Author

Stöhlker, Th., Bagnoud, V., Blaum, K., Blazevic, A., Bräuning-Demian, A., Durante, M., Herfurth, F., Lestinsky, M., Litvinov, Y., Neff, S., Pleskac, R., Schuch, R., Schippers, S., Severin, D., Tauschwitz, A., Trautmann, C., Varentsov, D., and Widmann, E.

Published
2015
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9. Towards experiments with highly charged ions at HESR

Author

Thomas Köhler, Uwe Spillmann, Jan Glorius, Pierre-Michel Hillenbrand, Thomas Stöhlker, Rodolfo Sánchez, Yuri A. Litvinov, Siegbert Hagmann, Anton Kalinin, Angela Braeuning-Demian, S. Sanjari, and Nikolaos Petridis

Subjects
Condensed Matter::Quantum Gases, Physics, Atomic Physics (physics.atom-ph), FOS: Physical sciences, 01 natural sciences, 7. Clean energy, Physics - Atomic Physics, 010305 fluids & plasmas, 3. Good health, Ion, Chemical physics, 0103 physical sciences, ddc:530, Physics::Atomic Physics, Nuclear Experiment, 010306 general physics, Spectroscopy
Abstract

The atomic physic collaboration SPARC is a part of the APPA pillar at the future Facility for Antiproton and Ion Research. It aims for atomic-physics research across virtually the full range of atomic matter. A research area of the atomic physics experiments is the study of the collision dynamics in strong electro-magnetic fields as well as the fundamental interactions between electrons and heavy nuclei at the HESR. Here we give a short overview about the central instruments for SPARC experiments at this storage ring., 4 pages, 1 figures

Published
2019
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11. Ion slowing down and charge exchange at small impact parameters selected by channeling: Superdensity effects

Author

L’Hoir, A., Adoui, L., Barrué, F., Billebaud, A., Bosch, F., Bräuning-Demian, A., Bräuning, H., Cassimi, A., Chevallier, M., Cohen, C., Dauvergne, D., Demonchy, C.E., Giot, L., Kirsch, R., Gumberidze, A., Kozhuharov, C., Liesen, D., Mittig, W., Mokler, P.H., Pita, S., Poizat, J.-C., Ray, C., Roussel-Chomaz, P., Rothard, H., Rozet, J.-P., Stöhlker, Th., Tarisien, M., Testa, E., Toleikis, S., Toulemonde, M., and Vernhet, D.

Published
2006
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14. Spectroscopy of superheavy quasimolecules

Author

Verma, P., Mokler, P.H., Bräuning-Demian, A., Kozhuharov, C., Bräuning, H., Bosch, F., Liesen, D., Stöhlker, T., Hagmann, S., Chatterjee, S., Gumberidze, A., Reuschl, R., Schöffler, M., Spillmann, U., Orsic Muthig, A., Tachenov, S., Stachura, Z., and Wahab, M.A.

Published
2006
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25. Towards experiments with highly charged ions at HESR

Author

Sánchez, Rodolfo, primary, Braeuning‐Demian, Angela, additional, Glorius, Jan, additional, Hagmann, Siegbert, additional, Hillenbrand, Pierre‐Michel, additional, Kalinin, Anton, additional, Köhler, Thomas, additional, Litvinov, Yuri A., additional, Petridis, Nikolaos, additional, Sanjari, Shahab, additional, Spillmann, Uwe, additional, and Stöhlker, Thomas, additional

Published
2019
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27. Physics book : CRYRING@ESR

Author

Lestinsky, M., Andrianov, V., Aurand, B., Bagnoud, V., Bernhardt, D., Beyer, H., Bishop, S., Blaum, K., Bleile, A., Borovik, At., Bosch, F., Bostock, C. J., Brandau, C., Braeuning-Demian, A., Bray, I., Davinson, T., Ebinger, B., Echler, A., Egelhof, P., Ehresmann, A., Engström, Mats, Enss, C., Ferreira, N., Fischer, D., Fleischmann, A., Foerster, E., Fritzsche, S., Geithner, R., Geyer, S., Glorius, J., Goebel, K., Gorda, O., Goullon, J., Grabitz, P., Grisenti, R., Gumberidze, A., Hagmann, S., Heil, M., Heinz, A., Herfurth, F., Hess, R., Hillenbrand, P. -M., Hubele, R., Indelicato, P., Källberg, Anders, Kester, O., Kiselev, O., Knie, A., Kozhuharov, C., Kraft-Bermuth, S., Kuehl, T., Lane, G., Litvinov, Yu. A., Liesen, D., Ma, X. W., Maertin, R., Moshammer, R., Mueller, A., Namba, S., Neumeyer, P., Nilsson, T., Noertershaeuser, W., Paulus, G., Petridis, N., Reed, M., Reifarth, R., Reiss, P., Rothhardt, J., Sanchez, R., Sanjari, M. S., Schippers, S., Schmidt, Henning T., Schneider, D., Scholz, P., Schuch, Reinhold, Schulz, M., Shabaev, V., Simonsson, Ansgar, Sjöholm, Johannes, Skeppstedt, Örjan, Sonnabend, K., Spillmann, U., Stiebing, K., Steck, M., Stohlker, T., Surzhykov, A., Torilov, S., Trabert, E., Trassinelli, M., Trotsenko, S., Tu, X. L., Uschmann, I., Walker, P. M., Weber, G., Winters, D. F. A., Woods, P. J., Zhao, H. Y., Zhang, Y. H., Lestinsky, M., Andrianov, V., Aurand, B., Bagnoud, V., Bernhardt, D., Beyer, H., Bishop, S., Blaum, K., Bleile, A., Borovik, At., Bosch, F., Bostock, C. J., Brandau, C., Braeuning-Demian, A., Bray, I., Davinson, T., Ebinger, B., Echler, A., Egelhof, P., Ehresmann, A., Engström, Mats, Enss, C., Ferreira, N., Fischer, D., Fleischmann, A., Foerster, E., Fritzsche, S., Geithner, R., Geyer, S., Glorius, J., Goebel, K., Gorda, O., Goullon, J., Grabitz, P., Grisenti, R., Gumberidze, A., Hagmann, S., Heil, M., Heinz, A., Herfurth, F., Hess, R., Hillenbrand, P. -M., Hubele, R., Indelicato, P., Källberg, Anders, Kester, O., Kiselev, O., Knie, A., Kozhuharov, C., Kraft-Bermuth, S., Kuehl, T., Lane, G., Litvinov, Yu. A., Liesen, D., Ma, X. W., Maertin, R., Moshammer, R., Mueller, A., Namba, S., Neumeyer, P., Nilsson, T., Noertershaeuser, W., Paulus, G., Petridis, N., Reed, M., Reifarth, R., Reiss, P., Rothhardt, J., Sanchez, R., Sanjari, M. S., Schippers, S., Schmidt, Henning T., Schneider, D., Scholz, P., Schuch, Reinhold, Schulz, M., Shabaev, V., Simonsson, Ansgar, Sjöholm, Johannes, Skeppstedt, Örjan, Sonnabend, K., Spillmann, U., Stiebing, K., Steck, M., Stohlker, T., Surzhykov, A., Torilov, S., Trabert, E., Trassinelli, M., Trotsenko, S., Tu, X. L., Uschmann, I., Walker, P. M., Weber, G., Winters, D. F. A., Woods, P. J., Zhao, H. Y., and Zhang, Y. H.

Abstract

The exploration of the unique properties of stored and cooled beams of highly-charged ions as provided by heavy-ion storage rings has opened novel and fascinating research opportunities in the realm of atomic and nuclear physics research. Since the late 1980s, pioneering work has been performed at the CRYRING at Stockholm (Abrahamsson et al. 1993) and at the Test Storage Ring (TSR) at Heidelberg (Baumann et al. 1988). For the heaviest ions in the highest charge-states, a real quantum jump was achieved in the early 1990s by the commissioning of the Experimental Storage Ring (ESR) at GSI Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt (Franzke 1987) where challenging experiments on the electron dynamics in the strong field regime as well as nuclear physics studies on exotic nuclei and at the borderline to atomic physics were performed. Meanwhile also at Lanzhou a heavy-ion storage ring has been taken in operation, exploiting the unique research opportunities in particular for medium-heavy ions and exotic nuclei (Xia et al. 2002).

Published
2016
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28. APPA at FAIR : From fundamental to applied research

Author

Stoehlker, Th., Bagnoud, V., Blaum, K., Blazevic, A., Braeuning-Demian, A., Durante, M., Herfurth, F., Lestinsky, M., Litvinov, Y., Neff, S., Pleskac, R., Schuch, Reinhold, Schippers, S., Severin, D., Tauschwitz, A., Trautmann, C., Varentsov, D., Widmann, E., Stoehlker, Th., Bagnoud, V., Blaum, K., Blazevic, A., Braeuning-Demian, A., Durante, M., Herfurth, F., Lestinsky, M., Litvinov, Y., Neff, S., Pleskac, R., Schuch, Reinhold, Schippers, S., Severin, D., Tauschwitz, A., Trautmann, C., Varentsov, D., and Widmann, E.

Abstract

FAIR with its intense beams of ions and antiprotons provides outstanding and worldwide unique experimental conditions for extreme matter research in atomic and plasma physics and for application oriented research in biophysics, medical physics and materials science. The associated research programs comprise interaction of matter with highest electromagnetic fields, properties of plasmas and of solid matter under extreme pressure, density, and temperature conditions, simulation of galactic cosmic radiation, research in nanoscience and charged particle radiotherapy. A broad variety of APPA-dedicated facilities including experimental stations, storage rings, and traps, equipped with most sophisticated instrumentation will allow the APPA community to tackle new challenges. The worldwide most intense source of slow antiprotons will expand the scope of APPA related research to the exciting field of antimatter.

Published
2015
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29. Ion-optical design of CRYRING@ESR

Author

Gorda, O., Braeuning-Demian, A., Danared, Håkan, Dolinskii, A., Engström, Mats, Herfurth, F., Källberg, Anders, Kleffner, C-M, Lestinsky, M., Simonsson, Ansgar, Sjöholm, Johannes, Vorobjev, G., Gorda, O., Braeuning-Demian, A., Danared, Håkan, Dolinskii, A., Engström, Mats, Herfurth, F., Källberg, Anders, Kleffner, C-M, Lestinsky, M., Simonsson, Ansgar, Sjöholm, Johannes, and Vorobjev, G.

Abstract

In 2012 the CRYRING storage ring was delivered from Stockholm to Darmstadt as a part of the Swedish in-kind contribution to the FAIR project. The ring lattice has been slightly changed for optimal injection and to provide additional space for experiment equipment. For the injection from the experimental storage ring (ESR), a new transfer line has been designed. The local injector line has been significantly modified compared to the previous one in Stockholm taking into account the geometry of the existing GSI building. In this paper we present the ion-optical properties of CRYRING@ESR after the described modifications. Single-turn injection from the ESR and multi-turn injection from the local injector are discussed. Ion-optical calculations of fast and slow extraction from CRYRING are also presented. The closed orbit correction scheme is considered taking into account the future arrangement of the beam position monitors and correction magnets. Based on the results of the calculations the requirements for the magnet alignment are finally discussed.

Published
2015
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31. Measurements of high energy loss rates of fast highly charged U ions channeled in thin silicon crystals

Author

Dieter Liesen, Marius Chevallier, P. H. Mokler, C. Cohen, C. Kozhuharov, A. Braeuning-Demian, Denis Dauvergne, A. L'Hoir, J.-C. Poizat, Etienne Testa, H. Braeuning, Th Stoehlker, Marcel Toulemonde, Cédric Ray, Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), CAS-PHABIO, Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Electron density, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Electron capture, Electron, Condensed Matter Physics, Elementary charge, 01 natural sciences, Charged particle, 010305 fluids & plasmas, Electronic, Optical and Magnetic Materials, Ion, Crystal, Tunnel effect, 0103 physical sciences, Atomic physics, 010306 general physics, 61.85.+p, 34.70.+e
Abstract

The results of two channeling experiments show that highly charged heavy ions at moderate velocities ($v\ensuremath{\ll}{\mathit{Zv}}_{0}$) may lose more energy in the traversal of a thin crystal when they are injected along a major crystallographic direction than when they traverse the crystal in random conditions. This is due to the fact that the large reduction of electron capture probabilities allows them to keep their high electronic charge throughout the crystal, which is not the case for projectiles traveling in random conditions. Although channeled projectiles experience reduced electron densities, their energy loss rate, that is, at first order, proportional to the square of the ions charge, is then strongly enhanced. This feature could be used as a step for decelerating highly charged ions from the high energies that are needed to produce them, and also to improve our understanding of the slowing down of very highly charged projectiles at low velocities, for which the current perturbative models are not well suited.

Published
2011
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32. Ion-optical design of CRYRING@ESR

Author

Gorda, O, primary, Braeuning-Demian, A, additional, Danared, H, additional, Dolinskii, A, additional, Engstroem, M, additional, Herfurth, F, additional, Kaellberg, A, additional, Kleffner, C-M, additional, Lestinsky, M, additional, Simonsson, A, additional, Sjoeholm, J, additional, and Vorobjev, G, additional

Published
2015
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33. SPARC collaboration : new strategy for storage ring physics at FAIR

Author

Stoehlker, Thomas, Litvinov, Yuri A., Braeuning-Demian, Angela, Lestinsky, Michael, Herfurth, Frank, Maier, Rudolf, Prasuhn, Dieter, Schuch, Reinhold, Steck, Markus, Stoehlker, Thomas, Litvinov, Yuri A., Braeuning-Demian, Angela, Lestinsky, Michael, Herfurth, Frank, Maier, Rudolf, Prasuhn, Dieter, Schuch, Reinhold, and Steck, Markus

Abstract

SPARC collaboration at FAIR pursues the worldwide unique research program by utilizing storage ring and trapping facilities for highly-charged heavy ions. The main focus is laid on the exploration of the physics at strong, ultra-short electromagnetic fields including the fundamental interactions between electrons and heavy nuclei as well as on the experiments at the border between nuclear and atomic physics. Very recently SPARC worked out a realization scheme for experiments with highly-charged heavy-ions at relativistic energies in the High-Energy Storage Ring HESR and at very low-energies at the CRYRING coupled to the present ESR. Both facilities provide unprecedented physics opportunities already at the very early stage of FAIR operation. The installation of CRYRING, dedicated Low-energy Storage Ring (LSR) for FLAIR, may even enable a much earlier realisation of the physics program of FLAIR with slow anti-protons., AuthorCount:9

Published
2014
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34. Ion-optical design of CRYRING@ESR

Author

O. Gorda, M. Engstroem, F. Herfurth, Michael Lestinsky, A. Kaellberg, A. Dolinskii, Ansgar Simonsson, G. Vorobjev, Håkan Danared, J. Sjoeholm, A. Braeuning-Demian, and C. Kleffner

Subjects
Physics, Transfer line, Injector, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Closed orbit, law.invention, Ion, Nuclear physics, law, Lattice (order), Magnet, Mathematical Physics, Storage ring
Abstract

In 2012 the CRYRING storage ring was delivered from Stockholm to Darmstadt as a part of the Swedish in-kind contribution to the FAIR project. The ring lattice has been slightly changed for optimal injection and to provide additional space for experiment equipment. For the injection from the experimental storage ring (ESR), a new transfer line has been designed. The local injector line has been significantly modified compared to the previous one in Stockholm taking into account the geometry of the existing GSI building. In this paper we present the ion-optical properties of CRYRING@ESR after the described modifications. Single-turn injection from the ESR and multi-turn injection from the local injector are discussed. Ion-optical calculations of fast and slow extraction from CRYRING are also presented. The closed orbit correction scheme is considered taking into account the future arrangement of the beam position monitors and correction magnets. Based on the results of the calculations the requirements for the magnet alignment are finally discussed.

Published
2015
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35. Plasma parameters of MSE sustained high pressure glow discharges

Author

C. Penache, H. Schmidt-Boecking, A. Braeuning-Demian, M. Miclea, U. Ernst, and D. Penache

Subjects
Neon, Glow discharge, Argon, Materials science, chemistry, Absorption spectroscopy, Physics::Plasma Physics, Plasma parameters, chemistry.chemical_element, Plasma diagnostics, Atomic physics, Current density, Spectral line
Abstract

Summary form only given, as follows. In order to generate large area, DC driven glow discharges at elevated pressures, micro-structure-electrode (MSE) arrays have been implemented. The currently used microstructures consist of a matrix of holes perforated in a thin multilayer system made out of two metallic foils (copper) separated by a dielectric spacer (Kapton). Typical dimensions are: holes diameter 100 /spl mu/m, electrodes thickness 100 /spl mu/m, 50 /spl mu/m thick insulator and holes pitch 0.75 to 3 mm. Direct current microdischarges were produced in noble gases (e.g. argon, helium neon), air and mixtures thereof at pressure ranging from hundreds of mbar up to one atmosphere. The discharge current can vary from 0.1 to 20 mA/per hole at operation voltage around 200 V, leading to a current density up to 100 A/cm/sup 2/. Single discharges and arrays of up to 200 microdischarges without individual resistive ballast have been successfully operated. Current-voltage characteristics and the optical appearance are proving a stable, non-filamentary glow discharge but they are not giving any information about the plasma parameters. In order to estimate the electron density, electron temperature and gas temperature a single Ar discharge has been investigated via optical emission and absorption spectroscopy. The emission spectrum consists mainly of atomic transitions but spectral lines from singly charged ions are also present, revealing the presence of energetic electrons. The electron density was obtained from the analysis of Stark-broadened profiles of hydrogen Balmer spectral lines. Absorption measurements have been performed using a tunable diode laser as a light source. The absorption line profiles of neutral argon spectral lines (3p/sup 5/4p-3p/sup 5/4s transitions) have been studied. The MSE arrays are providing a non-equilibrium high pressure plasma which is very promising for surface processing and gas phase plasma chemistry.

Published
2002
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