Physics – Plasma Physics
Scientific paper
2005-08-31
Physics
Plasma Physics
55 pages, 5 tables, 12 figures
Scientific paper
In this paper the selective broadening of the atomic hydrogen lines in pure H2 and Ar/H2 mixtures in a large 'GEC' cell (36 cm length_ 14 cm ID) was mapped as a function of position, H2/Ar ratio, time, power, and pressure. Several observations regarding the selective line broadening were particularly notable as they are unanticipated on the basis of earlier models. First, the anomalous broadening of the Balmer lines was found to exist throughout the plasma, and not just in the region between the electrodes. Second, the broadening was consistently a complex function of the operating parameters particularly gas composition (highest in pure H2), position, power, time and pressure. Clearly not anticipated by earlier models were the findings that under some conditions the highest concentration of 'hot' (>10 eV) hydrogen was found at the entry end, and not in the high field region between the electrodes and that in other conditions, the hottest H was at the (exit) pump (also grounded electrode) end. Third, excitation and electron temperatures were less than one eV in all regions of the plasma not directly adjacent (>1mm) to the electrodes, providing additional evidence that the energy for broadening, contrary to standard models, is not obtained from the field. Fourth, in contrast to our earlier studies of hydrogen/helium and water plasmas, we found that in some conditions 98% of the atomic hydrogen was in the 'hot' state throughout the GEC-type cell. Virtually every operating parameter studied impacted the character of the hot H atom population, and clearly second and third order effects exist, indicating a need for experimental design. Some non-field mechanisms for generating hot hydrogen atoms, specifically those suggested by Mills' CQM model, are outlined.
Akhtar Kamran
Chen Chun-Ku
Dhandapani Bala
Mills Randell
Phillips Jonathan
No associations
LandOfFree
Evidence of catalytic production of hot hydrogen in rf generated hydrogen/argon plasmas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Evidence of catalytic production of hot hydrogen in rf generated hydrogen/argon plasmas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Evidence of catalytic production of hot hydrogen in rf generated hydrogen/argon plasmas will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-152015