Re: [fluka-discuss]: RE: Delta-ray production

From: Alfredo Ferrari <alfredo.ferrari_at_cern.ch>
Date: Mon, 10 Mar 2014 10:43:31 +0100

Dear Anna

surely it would be better to use the PRECISIOn default for your specific
problem and to activate explicitly for the Au-Au case both ElectroMagnetic
dissociation and heavy ion direct pair production (look at the PHYSICS
card for both).

The "step" that you see in the electron spectrum for the Au-Au case is
likely due to the different weigth of two components, a) the delta-rays
emitted by the ions, whose end-point is exactly where you see the "step"
as you can compute yourself, and b) the e-e+ coming from pi0 production
and gamma conversion or anyway more in general from nuclear interactions.

Both components exist for p-Au too, but the delta-ray component scales
like Z^2 (79^2) while the nuclear component scales with something
like A^2/3 -> ergo for the p-Au case the delta-ray component is much
smaller in a relative sense

                         Ciao
                        Alfredo

+----------------------------------------------------------------------+
| Alfredo Ferrari || Tel.: +41.22.76.76119 |
| CERN-EN/STI || Fax.: +41.22.76.69474 |
| 1211 Geneva 23 || e-mail: Alfredo.Ferrari_at_cern.ch |
| Switzerland || |
+----------------------------------------------------------------------+

On Mon, 10 Mar 2014, Senger, Anna Dr. wrote:

>
> Dear FLUKA experts.
>
> My question is rather important for CBM detector and electronics
> development. We found, that after 60 cm C absorber the ionizing energy loss
> due to electrons from the target is very high for 35 AGeV gold beam. We try
> to understand, it is realistic or not. I produced usrtrack-plot for
> electrons in 1mm from the target for Au and p beams. There is one step in
> the distribution for Au beam. Is it correct? And were all possible processes
> of the delta-electron production included for the Au beam for "NEW-DEFA"
> option?
>
>  
>
> Best regards
>
> Anna Senger
>
>  
>
> From: owner-fluka-discuss_at_mi.infn.it [mailto:owner-fluka-discuss_at_mi.infn.it]
> On Behalf Of Senger, Anna Dr.
> Sent: Mittwoch, 5. März 2014 14:25
> To: 'fluka-discuss_at_fluka.org'
> Subject: [fluka-discuss]: Delta-ray production
>
>  
>
> Dear FLUKA experts,
>
> I have a question about delta-ray production in target. I simulate Au beam _at_
> 35 AGeV, and I have 1% gold target.
>
> If I use "default" settings, is form factor included in delta-ray production
> in target?
>
>  
>
> Best regards
>
> Anna Senger
>
>
>
Received on Mon Mar 10 2014 - 11:39:13 CET