GEANT simulations

[Elton Smith <elton@jlab.org>]

Hi Richard,

We missed you this morning. Pavel came by my office and we chatted a
little about coordinating simulation efforts. It would be useful if you
could talk to him directly in any case. Here is some brief comments that
came out of our discussions:

Pavel has updated standard GEANT with photo-nuclear reactions
(including hadronic interactions from electrons). He confirmed that most
background is electromagnetic. There are a couple of instances where he
has seen that hadronic reactions are important: a) pi/e ratio at large
angles b) particles exiting a thick absorber (mostly neutrons), e.g.
calorimeter or magnet c) backsplash from calorimeter, etc.

We considered several options for proceding:

- Pavel would be happy to run his program with a Hall D geometry file
  (with his package turned off) and compare with one of your outputs
  to check consistency. He could then run the program with his package
  turned on to look for any places where hadronic reactions are important.

- Once the programs are compared, Pavel could give you his routines to
  be included into your calculations if that seemed useful.


Radiation Dose Rates

On another subject, i.e. radiation levels from Hall D, I told him that we
are converging on our civil design. We should give him our "final" civil
design so that he can simulate dose rates in and around the Hall. This
should be done in advance to sending the civil package to an A&E firm and
can serve as an update for the upcoming CDR. The rates in the DR are based
on civil design as of a year ago.

Cheers, Elton.



-- 
Elton Smith
Jefferson Lab
elton@jlab.org
(757) 269-7625