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CELL section:
It has been pointed out that, although the field is correctly computed in tubes, the charges used in these calculations have no physical meaning -- thus making the computation of the forces acting on the wires meaningless.
MAGNETIC-FIELD section:
No changes.
OPTIMISATION section:
No changes.
FIELD section:
No changes.
GAS section:
The possibility to enter a cluster size distribution partially as a table and partially as an asymptotic expression, has been added. This feature may be useful if the presence of very large cluster sizes is of importance.
In parallel, work is in progress to interface the HEED program of Igor Smirnov (Gatchina) with Garfield. The HEED program computes amongst others the cluster spacing and cluster size distribution in gas mixtures.
To handle the probability of very large cluster sizes more accurately, the random cluster size generator has been replaced by one that works with higher accuracy and better random number generators.
It has been found that the transverse diffusion inside Magboltz is defined in a frame with the electric field as one of the axes, whereas the transverse component in Garfield is orthogonal to the direction of motion. This inconsistency was discovered shortly before the release, and is therefore present in the currently distributed version.
DRIFT section:
As mentioned in the previous CNL, the component of the drift velocity parallel to B (the ' term') was missing if the Lorentz angle is tabulated. This term has been added in version 5.11.
The sign of the angle in XT-PLOT has been changed to bring it in line with the angle used by ARRIVAL and TIMING.
The random number generators used, for instance, for arrival time calculations are gradually being replaced by more modern ones.
SIGNAL section:
The Polya distribution has been added as an avalanche fluctuation type, either with a fixed mean or with a mean computed by integrating the Townsend coefficient.
Werner Riegler has found that the first part of the leading edge of the ion tails was missing. The missing part corresponds to the signal induced by the ions in the first, approximately,
25 % mu 'm'
after the wire. This, and a small mistake in the normalisation of the signals, has been corrected.
Graphics:
The graphics control functions have been made to work in HIGZ compilations, giving access to most HIGZ workstation types. The surface plots in &DRIFT and in &FIELD and the contour plot in &DRIFT TABLE have been made to work with HIGZ. The latter two require the colour definitions from the file described below.
There is a known problem with text plotted at an angle by HIGZ. This problem is being investigated.
An instruction has been added to inspect the set of colours currently defined (!MAP).
A file containing colour definitions and colour representations for many items is available. Users with a colour terminal are advised to read in this file at the beginning of a session. If the file is given the proper name, this will be done automatically at startup. The representation definitions can be modified and further colours can be added but the colours that are present should not be deleted. This file can also contain instructions to define further workstations.
Formulas:
Conditions on GLOBAL and CALL statements are now respected. Also, algebra translation of these statements is postponed to execution time in case the statements contain a pair.
To simplify entering character constants, a new delimiter, the reverse quote (`) has been introduced. This delimiter is similar to the single and double quote in that it keeps words containing separators together, and similar to the double quote in that there is no case conversion between a pair of reverse quotes. But it differs from the other kinds of quotes in that the quotes form part of the word. To illustrate its use, the two following (equivalent commands):
Global string '"a b c"' Global string `a b c`
An instruction (PARSE) has been added which permits obtaining user input while reading an input file.
Datasets and Input / Output:
At startup, a file called GARFINIT INPUT * (VM/CMS), GARFIELD.DAT or SYS$LOGIN:GARFIELD.DAT (Vax/VMS) or garfinit, ~/garfinit, ~/Garfield/Files/garfinit (Unix) will be read at startup, if the file exists. This permits a certain amount of tailoring of the graphics, see the graphics section for more details.
Histograms:
Corrected clearing global variables to which a histograms will be saved.
The errors on the fit parameters are now returned in the CALL statements -- Consult the manual for the new argument lists.
Global options:
An option (PROGRESS-PRINT) has been added to enable the user to follow the progress of some, particularly lengthy calculations. This option can be set, like the other global options, from the command line and is then called PROGRESS_PRINT or progress_print depending on the system.
Compilation:
No changes.
Front-end programs and EXEC files:
The front-end program on Vax now addresses all graphics systems at the same time. The CLD file has been rewritten, the advice of C. W. Hobbs /DEC is gratefully acknowledged.