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**Rob Veenhof, IPN Orsay and NIKHEF**

The main new feature of this version is the extension of the interface with the Maxwell finite element program, both for 2-dimensional and for 3-dimensional configurations.

`BACKGROUND-FIELD`

command.
`VIEWING-PLANE`

, has been added for making
plots of 2D cuts through 3D field maps,
The axis labeling for `PLOT SURFACE`

in HIGZ compilations
has been corrected (the x and y axis labels were interchanged).

An instruction, called `ADD`

, has been added which enables
one to add/replace elements to/of the gas tables.

Comparison of Magboltz calculations and measurements has shown that the
diffusions estimates returned so far by the interface are less accurate
than other estimates available in Magboltz.
After consultation with the Steve Biagi, the default set of diffusion
coefficients has been modified -- the old set can still be obtained via
options described in the
help file
(`http://consult.cern.ch/writeup/garfield/help`

).
The transverse diffusion is particularly affected by this modification.

We have also observed that the Townsend coefficients computed with the
`ITERATE-ALPHA`

and `SWITCH`

options,
although in principle more accurate, agree less well with the data for several
gasses than those computed with the `NOITERATE-ALPHA`

option.

The `AXES`

command has been extended and has been
renamed `PLOT-OPTIONS`

.

`CLUSTERING-HISTOGRAMS`

command
to enable user control of the histogram binning.
A numerical inaccuracy has been corrected in cells with 4 equipotential planes. Signals were accurate close to the wires, but inaccurate close to the planes.

Signals can now be computed on conductors for which a weighting
field has been entered via the `FIELD-MAP`

command in the
cell section.

The units of signals written out to a dataset are now under user control.

`ARROW-TOP-ANGLE`

graphics command.
Tickmarks were absent in the first decade of log scaled axes. This has been corrected now.

Two new models of markers have been added: `TRIANGLE`

and
`HEXAGON`

, the triangles can have 4 orientations.

`IGNORE-UNDERFLOW`

has been added to the
algebra subsection to set exponential underflows equal to zero,
without further warnings.
The argument list of procedure `GET_CLUSTER`

has been
modified to include the energy deposited in the cluster.

A mistake in the return arguments of `FIT_FUNCTION`

has
been corrected -- the correct results were displayed, but they were
not stored in the proper global variables.

Procedures have been added for the conversion between matrices
and histograms, `MATRIX_TO_HISTOGRAM`

and
`HISTOGRAM_TO_MATRIX`

.

A new procedure `AVALANCHE`

has been added.
This procedure is an extension of the Monte Carlo drift line integration
procedures in which the generation and absorption of electrons and ions
is simulated using the Townsend and attachment coefficients.
Secondary electrons and ions are traced, and can induce further avalanches.
Space charge is currently not taken into account.

`WRITE`

instructions now check whether the dataset
to be written to already contains a member of the same type and
with the same name.
A set of global options has been added to control the action to be
taken if such a member exists.
`http://consult.cern.ch/writeup/garfield/help`

),
the printed manual is not available at the moment, for lack of SGML at CERN.
A set of
examples
can be found on WWW
(`http://consult.cern.ch/writeup/garfield`

).