RE: particle distribution after the collimator

Dear FLUKA experts,

I succeeded with the FLUKA compilation. But, unfortunately, another problem is occurred. There are no data in the file RESULTS.TXT which I created in order to write the needed data there. Could you say what is wrong? In the attachment you can find the modified version of MGDRAW.F and unchanged input file.

Thank you for any suggestion.

Best regards,
Vitaliy

> -----Original Message-----
> From: owner-fluka-discuss_at_mi.infn.it
> [mailto:owner-fluka-discuss_at_mi.infn.it] On Behalf Of
> Andrea.Mairani_at_mi.infn.it
> Sent: 11 ноября 2009 г. 13:53
> To: fluka-discuss_at_fluka.org
> Subject: Re: particle distribution after the collimator
> Importance: High
>
>
> Dear Vitaly,
> I looked at your mgdraw.f, some comments:
> * you have to define
> CHARACTER*8 MRGNAM, NRGNAM
> * instead of
> IF ((MRGNAM.EQ."TARG".OR.MRGNAM.EQ."VOID").and.
> & JTRACK.EQ.1) THEN
> you have to use
> IF ((MRGNAM.EQ."TARG".AND.NRGNAM.EQ."VOID").and.
> & JTRACK.EQ.1) THEN
> if you want to score all particles leaving the target.
> On the contrary if you are interested on the forward emission
> after the target you have to define a tiny region at the end
> of the RCC ( for example using XYP 9.995).
>
> Ciao
> Andrea
>
>
> > Dear FLUKA experts,
> >
> > Recently I asked the FLUKA community about the way to obtain the
> > particle distribution after the collimators.
> >
> > ...I would kindly ask you to help me in solution of one problem. We
> > are going to calculate the passage of the particles through the
> > graphite collimators in details. This means that we want to
> know the
> > change of original particle distribution including particles going
> > directly through the graphite. There is a certain particle
> > distribution before the collimator. Then the particles pass mostly
> > through the collimator slit but part of them pass directly
> through the
> > collimator material. Graphite is not so effective as iron
> in sense of
> > particle cutting. The radiation length for graphite is about 30 cm
> > only. Therefore, we need longer collimators but, unfortunately, we
> > have not enough space for them. We are interested in
> particles which
> > can come to the transfer beam acceptance together with antiprotons,
> > for example, pions. Pions have similar rigidity in our case and
> > theoretically can be transport to the ring and make some
> harm there.
> > Could you recommend some proper way to obtain such a particle
> > distribution after collimator. Do we need some additional
> code? The
> > idea is to have a particle distribution before and after
> collimator in
> > order to understand how many particles can come to the
> septum magnet
> > of the following storage ring. It gives us an information about
> > possible problems...
> >
> > There were several useful recommendations but,
> unfortunately, I didn't
> > solve the problem up to now. I tried to use the MGDRAW
> subroutine and
> > wrote some lines in mgdraw.f (namely, in entry BXDRAW). I'm
> not sure
> > that this is correct and the best variant. In addition, maybe
> > something wrong with my input file. Nevertheless, there are some
> > errors occurred during compilation. Maybe I'm using the
> CALL GEOR2N in
> > wrong way because there are some errors due to different type of
> > variables. I didn't understand how it really works.
> >
> > I appreciate any help. Thank you in advance.
> >
> > Best regards,
> > Vitaliy Gostishchev
> >
> > p.s. In the attachment you can find my input and the
> modified MGDRAW.F
> > files. <<distribv1.inp>> <<mgdraw.f>>
> >
>
>