Elsevier Science Home
Computer Physics Communications Program Library
Full text online from Science Direct
Programs in Physics & Physical Chemistry
CPC Home

[Licence| Download | New Version Template] abhf_v1_0.gz(96 Kbytes)
Manuscript Title: Data base of cross sections and reaction rates for hydrogen ion sources.
Authors: K. Smith, A.H. Glasser
Program title: HIONDAT
Catalogue identifier: ABHF_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 54(1989)391
Programming language: Fortran.
Computer: VAX 11/750.
Operating system: VAX/VMS VERSION V4.4.
Word size: 32
Peripherals: disc.
Keywords: Molecular physics, Chemical reactions, Rate coefficients, Database, Plasma, Ion source.
Classification: 9, 16.8.

Nature of problem:
HIONDAT is a suite of programs to create, update, and use a permanent data base containing information relating to the cross sections and rate coefficients of chemical reactions in plasmas generated in hydrogen ion sources. In view of the lack of knowledge of cross sections at energies of interest for almost all processes thought to be important, it is necessary to distinguish here those cross sections that are known (by giving their source reference) from those that are conjectured, but that are required to model the ion source.

Solution method:
The cross section for each chemical reaction is typed into an ASCII file with the name REAC*.DAT, where * is the data base sequence number assigned to the reaction, as described later. These cross sections are either parametrized to a polynominal using Chebyshev functions and subsequently used in this form to calculate collision frequencies in elastic collisions, or fit to b-splines and used in this form to evaluate Maxwellian reaction rates, which are in turn fit to a polynominal using Chebyshev functions and used in this parametric form in a fluid model of the ion source.

The data base is designed to store three types of information: (1) the raw cross-section data, which must be typed in; (2a) Chebyshev-derived parameters to fit the cross sections and (2b) b-spline-derived parameters to fit the cross sections; (3) Chebyshev-derived parameters to Maxwellian reaction rates versus effective temperatures. To enlarge the data base, the user must extend the sequence number of the additional reactions, enlarge parametric dimensions, and extend various data statements in the FORTRAN code.

Running time:
It takes about 5 s to produce the b-spline fit and 100 s to produce the Chebyshev fit to the Maxwellian rate.