Skip to Content.
Sympa Menu

opal - Re: [Opal] ECOLLIMATOR -- questions/potential issue

opal AT

Subject: The OPAL Discussion Forum

List archive

Re: [Opal] ECOLLIMATOR -- questions/potential issue

Chronological Thread  
  • From: "Adelmann Andreas (PSI)" <andreas.adelmann AT>
  • To: Dragos Constantin <Dragos.Constantin AT>
  • Cc: "opal AT" <opal AT>
  • Subject: Re: [Opal] ECOLLIMATOR -- questions/potential issue
  • Date: Tue, 15 Sep 2020 18:57:40 +0000
  • Accept-language: en-US, de-CH

Dear Dragos, the collimator aperture can not be changed w.r.t. the local reference frame. 
I think you would need to estimate before running the simulation. Certainly one can
implement such a collimator model. If this is very important I can make a feature request
for you.
Cheers A
Dr. sc. math. Andreas (Andy) Adelmann
Head a.i. Labor for Scientific Computing and Modelling 
Paul Scherrer Institut OHSA/ CH-5232 Villigen PSI
Phone Office: xx41 56 310 42 33 Fax: xx41 56 310 31 91
Zoom ID: 470-582-4086 Password: AdA
Friday: ETH HPK G 28   +41 44 633 3076
The more exotic, the more abstract the knowledge, 
the more profound will be its consequences.
Leon Lederman 

On 12 Sep 2020, at 19:16, Dragos Constantin <dragos.constantin AT> wrote:

Hi All,
I have defined an ECOLLIMATOR like this:

BCOL: ECOLLIMATOR, L = 1, Z =0, X = 0, Y = 0, XSIZE = 0.002, YSIZE = 0.002, OUTFN = "BCOL";

so I have a circular aperture of 2mm radius. During the simulation the reference particle deviates from the central axis because of fields asymmetries. 

Is it possible that the circular aperture is defined with respect to the reference particle local reference frame instead of the laboratory reference frame?

It looks like the particles are no longer tracked if they are more than 2mm distance from the reference particle. I have attached two pictures that show the macroparticles bunch and the collimator wall from 2 different orrientations. On the 'cross section' view you can clearly see the circular aperture acting on the bunch but its position is obviously displaced to the right.



Archive powered by MHonArc 2.6.19.

Top of Page