[gate-users] uncorrelated random number seeds

[Hiroshi Watabe]

Dear Gate-users,

I try to do 4 simulations with different seeds. In the past gate-users
talk, I found the article (posted by Mutanga Theodore on 17 Dec 2004)
which explain how to generate different seeds files.
As the article explains, I did mock simulation with 10 Bq source and
generated four different endOfRun.rndm. By using the command
/random/resetEngineFrom, I initialized random seeds.
I supposed to get four different results but four simulations produced
very similar results. I say "similar" because I got exactly same
projection data but the root outputs were slightly different in each
others. In the root file, I found only event ID and time
were different but else (for instance, source position and global
position) were exactly same in Singles trees (I'm doing SPECT simulation).

Any suggestions and advice are appreciate.

Hiroshi

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             Hiroshi Watabe, PhD

watabe at ri.ncvc.go.jp
Department of Investigative Radiology
Advanced Medical Engineering Center
National Cardiovascular Center Research Institute

5-7-1 Fujishirodai, Suita, Osaka 565-8565

Tel:06-6833-5012-2560 or 06-6833-5004-2560
Fax:06-6835-5429
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