Re: [fluka-discuss]: Activating DPMJET in FLUKA

From: Luigi Salvatore Esposito <luigi.salvatore.esposito_at_cern.ch>
Date: Thu, 7 Aug 2014 08:18:08 +0000

Dear Graham, dear Sudeshna,

you’re correct to say that in FLUKA the simulation of proton-proton collisions at 14 TeV CMS energy falls in the realm of DPMJET.

In order to correctly setup the simulation with the DPMJET generator, you have to
1) link it explicitly via the linking script $FLUPRO/flutil/ldpm3qmd.
2) activate the card PHYSICS to set the maximum (pp) CMS momentum via WHAT(1). For example
PHYSICS 7700. LIMITS
where a set a value a bit higher the 7 TeV/c in order not to cut the initialisation tables exactly at beam momentum.

IONTRANS is not necessary, except if you’re interested in the transport of ions.

As you have noticed yourself, there are differences when DPMJET is activated. But the significance of these differences
depends on the observables you are considering.
To judge on the factor of 2-3, we would need more details.

Best regards,

-luigi
------------------------------------
Luigi Salvatore ESPOSITO
EN-STI-EET, CERN
tel: +41 (0)22 76 79132 | fax: +41 (0)22 76 68495
skype: luillo76



On 6 Aug 2014, at 21:34, Sudeshna Banerjee <Sudeshna.Banerjee_at_cern.ch<mailto:Sudeshna.Banerjee_at_cern.ch>> wrote:

---------- Forwarded message ----------
From: Graham Stoddard <stoddarg_at_gmail.com<mailto:stoddarg_at_gmail.com>>
Date: Tue, Aug 5, 2014 at 11:06 AM
Subject: Activating DPMJET
To: fluka-discuss_at_fluka.org<mailto:fluka-discuss_at_fluka.org>


Dear Experts,

I am trying to simulate proton-proton collisions inside the CMS geometry using 7 TeV protons. This falls in the realm of DPMJET, but when I run simulations then look at the run001.out file, there is no mention of DPMJET. As far as I can tell, DPMJET is one of the standard event generators that FLUKA uses, so for my simulation is it enough to just have a high energy beam defined or do I also need to manually link DPMJET/RQMD? I am running the latest version of FLUKA available on the website. Additionally I see this for both the 32- and 64-bit versions.

When I do link DPMJET (using ldpmqmd) I see in the run001.out file that DPMJET is activated. The problem is that after processing the data (USRBIN scorings), it looks very similar as before linking DPMJET, but scaled up by a factor of 2-3. So, for proton-proton collisions at high energy is it enough just to link DPMJET or are there other cards (IONTRANS, PHYSICS, etc.) that should be included?

Regards,
Graham Stoddard
Received on Thu Aug 07 2014 - 11:45:55 CEST