Search found 19 matches

by jcalvey
06 Dec 2021, 13:14
Forum: Ring Tracking
Topic: Beam ion interaction using IONEFFECTS element
Replies: 16
Views: 9961

Re: Beam ion interaction using IONEFFECTS element

Saroj and Tiansk, These are all good questions. Please be patient, I'm working through them in the order received Find the elegant files with which the result was obtained, which may give some clue for the output or where I am doing mistake. In your example file, is atrain.sdds the full bunch train?...
by jcalvey
05 Dec 2021, 13:06
Forum: Ring Tracking
Topic: Beam ion interaction using IONEFFECTS element
Replies: 16
Views: 9961

Re: Beam ion interaction using IONEFFECTS element

Tiansk, Why is the first and last different from the others? How is ion generation handled in the program? For uniformly filled beam mode,I guess the qIons_delta should be the same,but in the ion1.ionDens file,the qIons_delta not quite the same. There are two reasons for this. First, in the example ...
by jcalvey
03 Dec 2021, 17:14
Forum: Ring Tracking
Topic: Beam ion interaction using IONEFFECTS element
Replies: 16
Views: 9961

Re: Beam ion interaction using IONEFFECTS element

Saroj, In plotting the ion density with the scripts, it does not plot the ion density since beginning. Please find the figure in the attachment. The script plots the ion density at the end of each turn. So for your case, it looks like the density is near its maximum after a single turn. I am using t...
by jcalvey
12 Nov 2021, 13:10
Forum: Ring Tracking
Topic: Beam ion interaction using IONEFFECTS element
Replies: 16
Views: 9961

Re: Beam ion interaction using IONEFFECTS element

Hello Saroj, This series of commands will plot the average ion density of the APS ring: sddsprocess ion1.ionDens -pipe=out -process=qIons,last,qLast | sddscollapse -pipe | sddsbreak -pipe=in ion1.ionDens.break -decreaseOf=s sddsprocess ion1.ionDens.break -process=qLast,sum,qTot -process=Pass,first,i...
by jcalvey
19 Oct 2021, 19:26
Forum: Ring Tracking
Topic: Coupled motion between ions & e-beam simulation using ion_effects
Replies: 5
Views: 1611

Re: Coupled motion between ions & e-beam simulation using ion_effects

You are right that the ionEffects1 example is old. I will work on making a new one when I have a chance. To answer your questions: 1. No, you don't have to. 2. I believe in this case it would generate a macroparticle with zero charge (but which would still receive beam kicks). I should probably add ...
by jcalvey
15 Oct 2021, 12:02
Forum: Ring Tracking
Topic: Coupled motion between ions & e-beam simulation using ion_effects
Replies: 5
Views: 1611

Re: Coupled motion between ions & e-beam simulation using ion_effects

Hi Tiansk, Sorry for the slow reply, I just now saw this post. I would not recommend using RING_ILM_NOSR. It was used for testing purposes, but won't give you accurate results. I'm not sure what the minimum number of interaction points required is to get a good result, but it's definitely more than ...
by jcalvey
15 Jan 2021, 17:27
Forum: Ring Tracking
Topic: Placement of IONEFFECTS elements
Replies: 7
Views: 7942

Re: Placement of IONEFFECTS elements

Yes, I would recommend trying more ion interaction points.

If that doesn't work, you can send some plots of your results to me (jcalvey@anl.gov) and I'll see if I can help figure out what's wrong.

-Joe
by jcalvey
12 Jan 2021, 18:23
Forum: Ring Tracking
Topic: Placement of IONEFFECTS elements
Replies: 7
Views: 7942

Re: Placement of IONEFFECTS elements

Hi Teresia, That error just means that one of the attempted fits failed (the code tries multiple starting points in parameter space). If the final fits in the .ionHist file look ok, then you can ignore the error. That being said, I would recommend that you start by using the gaussian kick method. It...
by jcalvey
08 Jan 2021, 12:49
Forum: Ring Tracking
Topic: Placement of IONEFFECTS elements
Replies: 7
Views: 7942

Re: Placement of IONEFFECTS elements

Hi Teresia, In general, the placement of the IONEFFECTS elements can be important. By default, the ionEffects1 example uses the RING_ILM10 beamline, which divides the ring into 10 ILMATRIX elements, with ion IONEFFECTS elements in between. In order to put the elements at specific locations, you woul...