TRACKER is a particle tracking Monte Carlo
which uses GEANT to track all manner of particles through IMB3,
BeamTest and SuperK detectors. It includes a custom light tracking
package which provides a detailed simulation of the response of the
detector to light produced by relativistic particles. Data can be
written in a variety of formats. The most prominent are the IMB mine
format, and the SuperK Interim format.
This document is divided into a number of sections. After you are
familiar with TRACKER you can skip to the section on options, environment
variables, or the kinematics file.
You may also want to see the change log or the to do list.
TRACKERTRACKER lives on //hepxvt.ps.uci.edu/superk.
There is not a good way to get the source yet, but I'll try to set up
some way to get it over the web soon.
TRACKER source.
GEANT. I recommend GEANT(3.16).
TRACKER has not been throughly tested with later versions
and the flags are set for GEANT(3.16). If you use a
later version, check that the hadronic packages is producing realistic
results since this is an active area of GEANT
development. By default TRACKER produces histograms that
summarize the range and cross-section data. Here is a thumbnail sketch of what needs to be done.
TRACKER on VMS
you need the command file build_tracker. Copy it to the directory
that will hold the source and executables, then run build_tracker.com
(e.g. $ @build_tracker.com). It will generate the source
files and compile them.
By now all of the source files and object files exist in the current
directory. When build_tracker was running it generated a
file tracker.lnk which will link TRACKER
with GEANT. It also generated the file cernlib.opt which you will
need to edit to reflect the location of cernlib. To link tracker run
tracker.lnk (e.g. $ @tracker.lnk).
The only thing left to do is to set TRKHOME in
tracker.com so that it points to the directory containing
the executable.
TRACKER is meant to be run from the command line. For unix a
typical command line might look like:
% tracker -O=interim electron.kin electron.mc91For VMS this becomes something like:
$ @tracker.com $ tracker "-O=interim" electron.kin electron.mc91
TRACKER. There are several options that are meant for
debugging the code that I have not documented, mainly because their
meaning changes as the debugging needs change. Be careful on VMS.
You must enclose options in double quotes since TRACKER
is case sensitive.
TRACKER command. Default: The kinematics are read from
stdin.
TRACKER. Default: Set
by the kinematics file.
TRACKER uses logicals and environment variables to
control a few of it's functions. The environment variables used are:
TRACKER has no mechanisms to generate event kinematics.
The program was structured this way since the generation of event
kinematics and the tracking of particles in the detector are
completely different problems that have almost nothing in common. By
separating the generation of event kinematics from the tracking of
particles multiple models of primary interactions can be developed and
easily compared using the same particle tracking simulation. This
allows the interaction models to be easily compared.
Event kinematics are fed to TRACKER via
kinematics file. A kinematics file is just a text file that contains
event descriptions. There is an added bonus that a kinematics file is
(almost) human readable. For example here is a simple file that
generates a single electron of 0.5 GeV going straight down from the
center of the detector:
** electron.kin begin ** TellTRACKERI want the output in electron.mc91 $ FILE electron.mc91 TellTRACKERI want the vertex at x=0, y=0 and z=0. $ VERTEX 0.0 0.0 0.0 TellTRACKERI want an electron going down with 0.5 GeV of total energy. $ PARTICLE 3 0.5 0.0 0.0 -1.0 TellTRACKERto list what is being generated. $ LIST TellTRACKERto generate the event. $ TRACK All done now. $ END ** electron.kin **
TRACKER only pays attention to the lines that have a "$"
as the first non-space character. Any line that does not begin with a
"$" is passed onto the log file. This allows the kinematics program
to pass comments on through TRACKER. The following is a
list of commands that TRACKER recognizes.
TRACKER that this is the end of the
kinematics file. This is required if the kinematics are being read
from stdin. That's really important so I'm going to repeat it. If
the kinematics is being read from stdin then the last command MUST be
"$END" or TRACKER will hang forever waiting for input.
If the kinematics are being read from a file then the end of file has
the same effect as "$END".
TRACKER does nothing to enforce the file extensions. For
unix systems TRACKER keeps a version number to prevent
output files from overwriting each other. TRACKER always
produces an rzdat file, which has a name and version based on
filename.
TRACKER and are used to pass kinematic information to
the output file. The basic parameters are: the GEANT
particle id "ipart", the total energy of the particle in GeV and the
direction of the particle (not normalized).
INCOMING and OUTGOING are used to specify the particles which
participate in the primary interaction, ie the initial and final
states of the Feynman diagram for this particular interaction.
INCOMING specifies the incoming particle. The fifth parameter is used
to pass the weight of the particle so that TRACKER
results can be re-weighted to account for other primary fluxes.
OUTGOING specifies the outgoing particles before any nuclear
corrections. The fifth parameter is used to specify the interaction
channel that generated the particles.
This code is maintained by:
cmcgrew@uci.edu$Id: tracker.html,v 1.2 1994/10/03 19:18:32 superk Exp $ $Log: tracker.html,v $ # Revision 1.2 1994/10/03 19:18:32 superk # Made the history of this file visible from the reader. # # Revision 1.1 1994/10/03 19:06:34 superk # Initial revision #