The OPAL Discussion Forum

[Norman Huang <norman-huang AT hotmail.com>]

After digging further into the code, it's apparent that a 3DDyanmic map (at least the FM3DDyanmic class) cannot be used to model quadrupoles. 

In line 171-176:

            FieldstrengthEz_m[i] /= Ezmax;

            FieldstrengthEx_m[i] /= Ezmax;

            FieldstrengthEy_m[i] /= Ezmax;

            FieldstrengthHz_m[i] /= Ezmax;

            FieldstrengthHx_m[i] /= Ezmax;

            FieldstrengthHy_m[i] /= Ezmax;

In a quadrupole, the Ez component is ideally 0, which makes this scaling function non physical. 

Is there an alternative way to specify an electric field map that only has non-zero values in the X and Y direction? Otherwise I'll be looking to creating a new field map class.

Regards,

Norman

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From: norman-huang AT hotmail.com
To: srussell AT lanl.gov; andreas.adelmann AT psi.ch; opal AT lists.psi.ch
CC: krab AT triumf.ca; raoyn AT triumf.ca; tplanche AT triumf.ca
Subject: Using a 3DDynamic Field Map
Date: Mon, 17 Oct 2011 15:02:17 -0700

Hi everyone,

So we were able to get a somewhat reasonable result using both an analytic electrostatic and magnetic quadrupole, but with some errors in the position of the focal point.

We now want to do the same simulations, but use a field map instead of the analytic models. Previously, Andreas had suggested the use of 3DDynamic field map with very low frequency to mimic a 3D Electrostatic field map, as that function is yet to be implemented. 

I was wondering if anyone has an example that actually uses a 3DDyanmic map; all the examples I have on hand are ASTRA maps attached to RFCAVITIES and SOLENOID elements.

Thanks,

Norman