Before we get to specifying event types, let's look at an event:
A. Type gen_event_ID_number>1000 and then hit return
(Don't worry about what this means, we'll get to that in the next
section. Suffice to say we're getting past the first thousand
pedestal events). You will see a ``3D'' graphic of the detector stack
of whichever spectrometer you chose at step 2.3. You can then pick
from three different viewpoints:
Viewpoint ``a''; the perspective view. This view is a 3D shot of the detector stack. The wires are colored only if they are hit, and hit scintillators and calorimeter blocks are colored blue. Tracks show up as red and blue lines (significance discussed later). There is also a blow up of the wire chambers at the lower right. This view is especially helpful in understanding the wire chambers' response. Note that in some cases the wires will extend past the edges of the chamber. If this bothers you I can point you to the source code.
Viewpoint ``b''; the side views. This view is pretty self-explanatory. The coloring of the detectors is the same as for view ``a''.
Viewpoint ``c''; the head on or ``mental gymnastics'' view. This is a head on, what-the-particle-sees, view of only the wire chambers. The track shows up, forshortened, as a red or blue line. It should intersect the wires (the rest of the colored lines) at x's. Dark wires are in the front, and light wires are in the back. This information, in addition to flipping back and forth between the ``a'' view, should be enough to figure out what happened with the chambers. Good luck.
Note: You may see some numbers like 958034 fly by. What can I say? GEANT never ceases to confound me.
B. Don't do this now, but to quit the program, type QUIT or EXIT to exit, or just hit Ctrl-C. Note that this will quit the display and not the engine. You can start up the display again and pick up the events where you left off (well, one event after where you left off).