Intensity distributions of enhanced H emission from laser-induced low-pressure He plasma and a suggested He-assisted excitation mechanism

Journal Article · Sat Aug 15 00:00:00 EDT 2009 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3195087· OSTI ID:21361774

Lie, Zener Sukra; Pardede, Marincan; Hedwig, Rinda; Suliyanti, Maria Margaretha; Steven, Eden; Maliki,; Kurniawan, Koo Hendrik ^[1]; Ramli, Muliadi ^[2]; Abdulmadjid, Syahrun Nur; Idris, Nasrullah; Lahna, Kurnia ^[3]; Kagawa, Kiichiro ^[4]; Tjia, May On ^[5]

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1. Research Center of Maju Makmur Mandiri Foundation, 40 Srengseng Raya, Kembangan, Jakarta Barat 11630 (Indonesia)
2. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh, Nanggroe Aceh Darussalam 23111 (Indonesia)
3. Department of Physics, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh, Nanggroe Aceh Darussalam 23111 (Indonesia)
4. Department of Physics, Faculty of Education and Regional Studies, Fukui University, 9-1 bunkyo 3-chome, Fukui 910-8507 (Japan)
5. Physics of Magnetism and Photonics Group, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, 10 Ganesha, Bandung 40132 (Indonesia)

An experimental study was conducted on the spatial distributions of hydrogen emission intensities from low-pressure plasmas generated by laser ablation of zircaloy-4 and black stone targets in nitrogen and helium ambient gases. In addition to confirming the previously observed intensity enhancement effect in ambient helium gas, the hydrogen and helium emission intensities measured along the plasma expansion direction revealed remarkable extended spatial distributions featuring unexpected maxima near the far end of the plasma where the available shock-wave generated thermal excitation energy should have been significantly reduced. This 'anomalous' feature necessarily implied the presence of an additional excitation process beside the well known shock-wave excitation process which is responsible for the plasma emission of heavy atoms in low-pressure ambient gas. Further analysis of the data led to a suggested physical mechanism explaining the possible contribution of a helium metastable excited state to the unusual phenomenon observed in this experiment.

• OSTI ID: 21361774
• Journal Information: Journal of Applied Physics, Vol. 106, Issue 4; Other Information: DOI: 10.1063/1.3195087; (c) 2009 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
36 MATERIALS SCIENCE
ABLATION
HELIUM
HYDROGEN
LASERS
METASTABLE STATES
NITROGEN
PLASMA
PLASMA EXPANSION
PLASMA PRODUCTION
SHOCK WAVES
SPATIAL DISTRIBUTION
ZIRCALOY 4
ALLOYS
ALLOY-ZR98SN-4
CHROMIUM ADDITIONS
CHROMIUM ALLOYS
CORROSION RESISTANT ALLOYS
DISTRIBUTION
ELEMENTS
ENERGY LEVELS
EXCITED STATES
EXPANSION
FLUIDS
GASES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ADDITIONS
IRON ALLOYS
MATERIALS
NONMETALS
RARE GASES
TIN ALLOYS
TRANSITION ELEMENT ALLOYS
ZIRCALOY
ZIRCONIUM ALLOYS
ZIRCONIUM BASE ALLOYS