Week Four

Learning the “real” software, continued

Alex George


Monday, June 16, 2008—

After our unexpectedly long weekend, Dr. Horton-Smith showed us how to install Geant 4, even writing a macro that we could copy to get the software to work.  We spent the rest of the day trying to duplicate his instructions on our computers, and working across the additional snags that we hit on our own machines.  We finally seemed to have it all working properly, however.   

Tuesday, June 17, 2008—

We ran “lytest,” a macro that was written exclusively for testing to make sure that the installation seemed to be working properly.  Dr. Horton-Smith then showed us the documentation online so that we could continue to learn Geant 4, and asked us to modify lytest to simulate a very similar, but different, effect, and to use root to make a histogram of that data.  It took us the rest of the day to get this working properly, but we had finally done our first actual simulation!  We then experimented with outputting root histograms in various colors. 

Wednesday, June 18, 2008—

We continued to fiddle with our programs while awaiting instruction.  Late in the afternoon, we were given choices of things that we could simulate in the next few weeks, things much more complicated than what we had already done.  I chose to model spill-in/spill-out effects – the chance that a particle generated on the inside would be captured outside the detector, or alternatively the chance that a particle generated outside the detector would be captured on the inside.  By understanding this effect, it would be possible to know if this effect were significant enough to warrant not using parts of the detector, or whether this could just be subtracted off as background noise. 

Ethics class today!

Thursday, June 19, 2008 –

Thursday was spent reading and trying to learn more about the spill-in/spill-out effect.  Unfortunately, not much literature is available on this subject, so many searches were in vain.

Friday, June 20, 2008 —

Friday morning was a continuation of “background reading” or lack thereof.  After lunch, Dr. Horton-Smith worked with us to help us write our macros for the simulation itself, since he and Dr. Bolton would be away all of next week.