RE: Using DOSE-EQ with USRYIELD

Thanks for confirming that - just one more question:
Since the fluence has a dependence on (1/cos theta), where theta is the
angle between the particle track and the normal to the surface it is
crossing, this must mean that I have to consider each of the end
surfaces and the side surface of the lead cylinder separately, so for
particles escaping the target through its end, I should only normalise
by the area of that end, and so on.

I am a bit confused by this, because in the previous course notes, the
USRBDX example shows normalisation of fluences over the total area of
the side and end faces of a cylindrical target:
 http://www.fluka.org/content/course/NEA/lectures/Scoring.pdf (on page
12)
Won't this result in an underestimate, because it does not take account
of which surface the particles are crossing ? It seems strange that
particle fluence through the end of the target should be normalised by a
surface area which includes the sides of the target.

Frances

-----Original Message-----
From: Lucia Sarchiapone [mailto:Lucia.Sarchiapone_at_lnl.infn.it]=20
Sent: 26 March 2009 15:56
To: Burge, F (Frances)
Cc: fluka-discuss_at_fluka.org
Subject: Re: Using DOSE-EQ with USRYIELD

Your card combination is correct,
so if you use the surface of the boundary between "LeadTarg" and
"Outervac" as normalization factor you will get pSv/GeV/sr per primary
particle.

Lucia

On Mar 24, 2009 03:59 PM, "Burge, F (Frances)"
<frances.burge_at_diamond.ac.uk> wrote:

> Dear Fluka users,
> I would like to use the USRYIELD card together with AUXSCORE to=20
> convert a photon fluence yield to dose equivalent around a lead=20
> target.
> So I have set up the following cards in my input file:
>=20
> USRYIELD 124 DOSE-EQ -24 LeadTarg Outervac 1.0 Flu_dos1
> USRYIELD 180. 0. 180. 3. 0. 6. &
> AUXSCORE USRYIELD PHOTON Flu_dos1 EWT74
>=20
> My first USRYIELD variable is lab polar angle in degrees, from 0 -=20
> 180, the second is particle energy with a single bin. I want to score=20
> dose equivalent in each of the angular bins if that is possible. The=20
> target is simply a ZCC, and the primary beam is travelling along the z

> axis.
> The quantity scored in USRYIELD is a double differential fluence=20
> yield, which if I was just scoring photons (rather than dose-eq) would

> be [photons/GeV/sr/cos theta].
>=20
> Now I guess what I get from the above cards is something like [pSv.cm2

> /GeV/sr] because of the folding of the dose coefficients with the=20
> fluence scoring.
>=20
> So the question is: If I normalise to the surface area of the lead=20
> target, will I be scoring the correct dose angular distribution in=20
> pSv/GeV/sr ? Or is the above combination of cards meaningless ?
>=20
> thanks for any suggestions,
> Frances
>=20
> Frances Burge
> Health Physicist
> 01235 778269
> Diamond Light Source Ltd.
> Harwell Science and Innovation Campus
> Didcot
> Oxfordshire
> OX11 0DE
> =20
> =20
> This e-mail and any attachments may contain confidential, copyright=20
> and or privileged material, and are for the use of the intended=20
> addressee only. If you are not the intended addressee or an authorised

> recipient of the addressee please notify us of receipt by returning=20
> the e-mail and do not use, copy, retain, distribute or disclose the=20
> information in or attached to the e-mail.
> Any opinions expressed within this e-mail are those of the individual=20
> and not necessarily of Diamond Light Source Ltd.
> Diamond Light Source Ltd. cannot guarantee that this e-mail or any=20
> attachments are free from viruses and we cannot accept liability for=20
> any damage which you may sustain as a result of software viruses which

> may be transmitted in or with the message.
> Diamond Light Source Limited (company no. 4375679). Registered in=20
> England and Wales with its registered office at Diamond House, Harwell

> Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United=20
> Kingdom
>=20
>=20

This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail.
Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd.
Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message.
Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
 
Received on Fri Mar 27 2009 - 12:25:23 CET