Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX
In the tandem mirror GAMMA 10/PDX, molecular activated recombination (MAR) leading to plasma detachment has been observed by additional hydrogen gas injection to the divertor simulation plasma (i.e. end loss plasma) which is exposed to the V-shaped target in the divertor simulation experimental modu...
| Main Authors: | , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2017-08-01
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| Series: | Nuclear Materials and Energy |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S235217911630254X |
| _version_ | 1811269881065111552 |
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| author | M. Sakamoto A. Terakado K. Nojiri N. Ezumi Y. Nakashima K. Sawada K. Ichimura M. Fukumoto K. Oki K. Shimizu N. Ohno S. Masuzaki S. Togo J. Kohagura M. Yoshikawa |
| author_facet | M. Sakamoto A. Terakado K. Nojiri N. Ezumi Y. Nakashima K. Sawada K. Ichimura M. Fukumoto K. Oki K. Shimizu N. Ohno S. Masuzaki S. Togo J. Kohagura M. Yoshikawa |
| author_sort | M. Sakamoto |
| collection | DOAJ |
| description | In the tandem mirror GAMMA 10/PDX, molecular activated recombination (MAR) leading to plasma detachment has been observed by additional hydrogen gas injection to the divertor simulation plasma (i.e. end loss plasma) which is exposed to the V-shaped target in the divertor simulation experimental module (D-module). The temperature near the corner of the V-shaped target decreased from ∼23eV to ∼2eV as the neutral pressure in the D-module increased. A clear density rollover was observed at ∼2Pa. A position of the density maximum moves to upstream of the plasma with increase in the neutral pressure and the density near the corner of the target decreases to detach the plasma from the target. After the occurrence of the density rollover, the Balmer β intensity decreases as with the density but the Balmer α intensity continues to increase, indicating the dissociative attachment process in MAR is more dominant than the ion conversion process although the rate coefficient of the former process is lower than that of the latter one, which is calculated by using a collisional radiative model. This would be caused by the MAR process related to triatomic hydrogen molecules which significantly contributed to the detachment process. |
| first_indexed | 2024-04-12T21:50:55Z |
| format | Article |
| id | doaj.art-97db3c2f4fe64b589df2c25e472a591c |
| institution | Directory Open Access Journal |
| issn | 2352-1791 |
| language | English |
| last_indexed | 2024-04-12T21:50:55Z |
| publishDate | 2017-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Nuclear Materials and Energy |
| spelling | doaj.art-97db3c2f4fe64b589df2c25e472a591c2022-12-22T03:15:30ZengElsevierNuclear Materials and Energy2352-17912017-08-011210041009Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDXM. Sakamoto0A. Terakado1K. Nojiri2N. Ezumi3Y. Nakashima4K. Sawada5K. Ichimura6M. Fukumoto7K. Oki8K. Shimizu9N. Ohno10S. Masuzaki11S. Togo12J. Kohagura13M. Yoshikawa14Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan; Corresponding author.Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanFaculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanNational Institutes for Quantum and Radiological Science and Technology, 801-1, Mukoyama, Naka, Ibaraki 311-0193, JapanGraduate School of Electrical and Electronic Engineering, Chiba University, Chiba 263-8522, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanGraduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, JapanNational Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanPlasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, JapanIn the tandem mirror GAMMA 10/PDX, molecular activated recombination (MAR) leading to plasma detachment has been observed by additional hydrogen gas injection to the divertor simulation plasma (i.e. end loss plasma) which is exposed to the V-shaped target in the divertor simulation experimental module (D-module). The temperature near the corner of the V-shaped target decreased from ∼23eV to ∼2eV as the neutral pressure in the D-module increased. A clear density rollover was observed at ∼2Pa. A position of the density maximum moves to upstream of the plasma with increase in the neutral pressure and the density near the corner of the target decreases to detach the plasma from the target. After the occurrence of the density rollover, the Balmer β intensity decreases as with the density but the Balmer α intensity continues to increase, indicating the dissociative attachment process in MAR is more dominant than the ion conversion process although the rate coefficient of the former process is lower than that of the latter one, which is calculated by using a collisional radiative model. This would be caused by the MAR process related to triatomic hydrogen molecules which significantly contributed to the detachment process.http://www.sciencedirect.com/science/article/pii/S235217911630254X |
| spellingShingle | M. Sakamoto A. Terakado K. Nojiri N. Ezumi Y. Nakashima K. Sawada K. Ichimura M. Fukumoto K. Oki K. Shimizu N. Ohno S. Masuzaki S. Togo J. Kohagura M. Yoshikawa Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX Nuclear Materials and Energy |
| title | Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX |
| title_full | Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX |
| title_fullStr | Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX |
| title_full_unstemmed | Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX |
| title_short | Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX |
| title_sort | molecular activated recombination in divertor simulation plasma on gamma 10 pdx |
| url | http://www.sciencedirect.com/science/article/pii/S235217911630254X |
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