CH spectroscopy for carbon chemical erosion analysis in high density low temperature hydrogen plasma

Westerhout, J.; Lopes Cardozo, N. J.; Rapp, J.; van Rooij, G. J.
October 2009
Applied Physics Letters;10/12/2009, Vol. 95 Issue 15, p151501
Academic Journal
The CH A-X molecular band is measured upon seeding the hydrogen plasma in the linear plasma generator Pilot-PSI [electron temperature Te=0.1–2.5 eV and electron density ne=(0.5–5)×1020 m-3] with methane. Calculated inverse photon efficiencies for these conditions range from 3 up to >106 due to a steeply decreasing electron excitation cross section. The experiments contradict the calculations and show a constant effective inverse photon efficiency of ∼100 for Te<1 eV. The discrepancy is explained as the CH A level is populated through dissociative recombination of the molecular ions formed by charge exchange. Collisional de-excitation is observed for ne>5×1020 m-3 and 0.1 eV


Related Articles

  • Detection of HF emission from the Orion Bar. van der Tak, F.F.S.; Ossenkopf, V.; Nagy, Z.; Faure, A.; Röllig, M.; Bergin, E. A. // Astronomy & Astrophysics / Astronomie et Astrophysique;Jan2012, Vol. 537, p1 

    Context. The clumpy density structure of photon-dominated regions is well established, but the physical properties of the clumps and of the surrounding interclump medium are only approximately known. Aims. The aim of this paper is to constrain the physical and chemical conditions in the Orion...

  • Divertor conditions relevant for fusion reactors achieved with linear plasma generator. van Eck, H. J. N.; Kleyn, A. W.; Lof, A.; van der Meiden, H. J.; van Rooij, G. J.; Scholten, J.; Zeijlmans van Emmichoven, P. A. // Applied Physics Letters;11/26/2012, Vol. 101 Issue 22, p224107 

    Intense magnetized hydrogen and deuterium plasmas have been produced with electron densities up to 3.6 × 1020 m-3 and electron temperatures up to 3.7 eV with a linear plasma generator. Exposure of a W target has led to average heat and particle flux densities well in excess of 4 MW m-2 and...

  • Aligning symmetric and asymmetric top molecules via single photon excitation. Weida, Miles J.; Parmenter, Charles S. // Journal of Chemical Physics;11/8/1997, Vol. 107 Issue 18, p7138 

    Studies the alignment of symmetric and asymmetric top molecules via single photon excitation. Theory developed by Zare for using electric-dipole-allowed photoexcitation; Analytical expression for the spatial distribution of a symmetric opt figure axis; Alignment via collisional processes.

  • Ultrafast Dynamics of 1,3-Cyclohexadiene in Highly Excited States. Bühler, Christine C.; Minitti, Michael P.; Deb, Sanghamitra; Bao, Jie; Weber, Peter M. // Journal of Atomic, Molecular & Optical Physics;2011, p1 

    The ultrafast dynamics of 1,3-cyclohexadiene has been investigated via structurally sensitive Rydberg electron binding energies and shown to differ upon excitation to the 1B state and the 3p Rydberg state. Excitation of the molecule with 4.63 eV photons into the ultrashort-lived 1B state yields...

  • Quenching of N[sub2](a[sup1]II[subg],& vacute; =0) by N[sub2], O[sub2], CO, CO[sub2], CH[sub4], H[sub2], and Ar. Marinelli, William J.; Kessler, William J.; Green, Byron David; Blumberg, William A.M. // Journal of Chemical Physics;2/15/1989, Vol. 90 Issue 4, p2167 

    Studies the quenching rate coefficients for nitrogen using two-photon laser excitation. Rate coefficient of quenching through collisional coupling; Collisional energy transfer; Gas-kinetic rate coefficients.

  • Simultaneous optical excitation of Na electronic and CF4 vibrational modes in Na+CF4 collisions. Alekseev, V. A.; Grosser, J.; Hoffmann, O.; Rebentrost, F. // Journal of Chemical Physics;11/28/2008, Vol. 129 Issue 20, p201102 

    We report on the ultraviolet excitation of Na(3s)+CF4 collision pairs in a crossed molecular beam experiment. We observe Na(3d) collision products originating from the process Na(3s)+CF4(ν3=0)+hν→Na(3d)+CF4(ν3=1). The spectral intensity distribution of the collision products and...

  • Electron distribution function and recombination coefficient in ultracold plasma in a magnetic field. Bobrov, A.; Bronin, S.; Zelener, B.; Manykin, E.; Khikhlukha, D. // Journal of Experimental & Theoretical Physics;Jul2013, Vol. 117 Issue 1, p161 

    The electron distribution function and diffusion coefficient in energy space have been calculated for the first time for a weakly coupled ultracold plasma in a magnetic field in the range of magnetic fields B = 100−50000 G for various temperatures. The dependence of these characteristics...

  • Relations between light emission and electron density and temperature fluctuations in a helium plasma. Ma, Shuiliang; Howard, John; Thapar, Nandika // Physics of Plasmas;Aug2011, Vol. 18 Issue 8, p083301 

    The relations between three atomic lines, He I 667.8 nm (31D → 21P), 706.5 nm (33S → 23P), and 728.1 nm (31S → 21P), and the underlying fluctuations in a helium plasma are investigated for the quantitative interpretation of optical observations in plasma fluctuation...

  • Study Of The Gas Balance By Injection Of Hydrocarbons Into The Plasma Simulator PSI 2. Bohmeyer, Werner; Markin, Andrey; Koch, Bernd; Krenz, Gordon; Fussmann, Gerd // AIP Conference Proceedings;2006, Vol. 812 Issue 1, p215 

    The stationary plasma of the plasma generator PSI 2 is used to study the gas balance of hydrocarbons and hydro-gen by means of mass spectrometers. For this purpose H2, acetylene and ethylene are injected into argon and hydrogen plasmas.. It is found that hydrogenation of the hydrocarbon layers...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics