From: Alberto Fasso' (fasso@SLAC.Stanford.EDU)
Date: Mon Oct 15 2007 - 15:04:20 CEST
I get the following message from Thomas Otto. See my answer below.
---------- Forwarded message ----------
Date: Mon, 15 Oct 2007 10:39:59 +0200
From: "Thomas Otto, SC-RP" <thomas.otto@cern.ch>
To: Alberto Fasso' <fasso@SLAC.Stanford.EDU>
Subject: Score 208
Dear Alberto,
I see that you are presently very active in answering e-mails on fluence and
such.
In the same ballbark, I have a remark concerning the manual: in the description
of USERWEIG, it states that a function call to comscw.f with What(6) = 1.0 will
also influence SCORE. I made recently a test, and this does not seem to be the
case. An absorbed energy binning (208) in USRBIN was converted into absorbed
dose, but the results under SCORE remined unaffected by comscw.f .
Anotyhe remark on the same command: the description of the use of WHAT(3 or 6)
> 2.0 is not very clear, I cannot understand the use of applying this. Is it
meant to be a timesaver by not calling a comscw-routine for a fluence estimator
?
If you think the answers to these qustions are of general interest, you can
post them on the fluka-list.
Best regards, Thomas
-- Thomas Otto Individual Dosimetry Service Radiation Protection PS Complex SC-RP CERN CH 1211 Geneve 23 Tel. (+41 22) 76 73272 Fax. (+41 22) 76 79360 thomas.otto@cern.ch http://cern.ch/rp-dosimetry ---------------------------------------------------------------------------- You are right, SCORE is not affected by comscw.f. It used to be affected in a very distant past (that is why the error in the manual), but for some reason that now nobody can recall this feature was abandoned. It is not a very important loss: you can obtain the same result by using "region binning" (USRBIN with WHAT(1) = 2). But I will correct the manual, of course. Concerning your second question (USERWEIG with WHAT(3) or WHAT(6) > 2), also here is a weakness of the manual that must be corrected (it says "see Note below", but the Note doesn't exist!). The meaning is the following: case 1) If the comscw.f or fluscw.f routine is used in a simple way, namely just to multiply the score by a factor (this happens in 99% of the cases!), it would be a waste of cpu time to evaluate the value of the function even when a detector or a binning are not affected by the current score. Setting WHAT(3) or WHAT(6) > 2 makes the program to evaluate the function only when it after making sure that a particular detector gets that score. case 2) But there are cases where the function is used for some "trick", not only to get a multiplication factor, but to obtain a side effect at a boundary crossing or at scoring time. The logics can be very complex and it is impossible to foresee. In this case, the evaluation is done before knowing if there is scoring or not in a particular detector, because that is not necessarily the trigger the user wants. I must admit that the default should better be the first case, and not the second. But unfortunately the code has been historically developed in this way and to change the default now could have bad effects on the legacy input of some user. I take this opportunity to point out that the fluence-to-dose equivalent conversion routine deq99 of Stefan Roesler, widely used in shielding calculations, should better be used as in case 1, unless a binning is used to cover the whole geometry (as it is now often the case to produce color plots). And not surprisingly, it was on Stefan's request that that the case 1 feature was added. Alberto
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