Projects / Programmes
Processes with vibrationally excited hydrogen molecules
| Code |
Science |
Field |
Subfield |
| 1.02.00 |
Natural sciences and mathematics |
Physics |
|
| Code |
Science |
Field |
| P230 |
Natural sciences and mathematics |
Atomic and molecular physics |
hydrogen molecule, vibrational excitation, dissociative attachment, recombination on surfaces, IBA methods, IBA methods, ERDA
Researchers (8)
Organisations (1)
| no. |
Code |
Research organisation |
City |
Registration number |
No. of publicationsNo. of publications |
| 1. |
0106 |
Jožef Stefan Institute |
Ljubljana |
5051606000 |
88,083 |
Abstract
We will study processes involving vibrationally excited hydrogen molecules (H2, D2 and HD) - collisions with electrons and processes at surfaces.
In particular, we will study dissociative electron attachment to hydrogen molecule that leads to formation of the stable negative ions H- or D-. Cross section for this process will be studied by an experimental set-up, that will be constructed for this purpose. The apparatus will be adapted for the use of low energy electron beam and for high selectivity and efficiency of low energy ion detection. This apparatus will be also used for diagnostics of vibrational population of hydrogen molecules. We will further improve method which we developed previously (Popović et al., Meas.Sci.Technol. 1 (1990) 1041) that is based on a strong increase of the dissociative attachment cross section with vibrational excitation of target hydrogen molecule.
the set-up for diagnostics of vibrational excitation of hydrogen molecules will be used for studies of surface reactions in which such molecules are formed (atom recombination, molecular desorption) or in which such molecules are incident projectiles (vibrational relaxation, adsorption). Studied surfaces will be exposed to the low-pressure neutral or weakly ionised hydrogen atmosphere of known dissociation rate and vibrational state distribution. Surface reactions to be studied are strongly related to the internal excitation of incident or product molecules. In order to acquire complete information on the process we will also measure in real time the hydrogen distribution beneath the surface. This will be performed by ERDA (Elastic Recoil Detection Analysis) an ion beam analysis method, which is available on our 2MV tandem accelerator.
Proposed research is important for understanding phenomena in edge plasma and in the plasma facing walls of the tokamak devices, for astrophysics and for understanding reactions at surfaces and in hydrogen containing plasmas.
