1. SC-25 FS1 Code Overview PTC-Orbit Synergia Micromap MAD-X with Frozen Space Charge 8/29/2013

2. SC-25 FS2 PTC-Orbit Support To get support for the PTC part by the authors Patrice Nishikawa/Alexander Molodozhentsev we have to follow a strict protocol and I will take care of that together with Laurent. Any direct contact to Patrice alias Etienne has to be avoided by all means!!! Side issue: Alexander’s account is still not back due to an incredible complex IT procedure ➔ mails to the service desk every other day! Our old supercode based ORBIT version will basically not be supported by the SNS ORBIT authors. However, we are in contact with them for the present trouble with the code. We do not have any real manual neither for ORBIT nor for the PTC part! Some of the examples AND the code is flawed ➔ Elena We have to wait till py-ORBIT is out including PTC and a manual. 8/29/2013

3. SC-25 FS3 PTC-Orbit Problems (complete?) Raymond found crashes and Harry has understood the main causes for this after a very painful debugging phase! Thanks Harry! ➔ his talk is next The code is intrinsically non-reproducible due to MPI issues! Harry and Igor Zacharov have ideas about how that might be overcome. Flaw in the coding of acceleration fixed by Elena ➔ see her talk The problem with the double RF system remains to be resolved as Vincenzo explained last time around. The issue of spikes in the emittance evolution as reported by Vincenzo/Elena remain to be resolved. The issue of un-physical core oscillations as discovered by Hannes for the SPS must also be addressed at some point. Jeff Holmes had no suggestion when it was presented to him. 8/29/2013

4. SC-25 FS4 PTC-Orbit Plan Finish the debugging both of ORBIT and the PTC part. Provide working examples for all relevant application. I would have expected that from Alexander but it did not come! Remember that I have provided a nice framework for a manual for PTC-ORBIT to be filled by all of us. This effort has to be started now because Alexander has refused to write a manual by himself. By the end of the year we have to switch over to py-ORBIT and hopefully that will go smoothly as advertized! Hopefully with manual! In case we find a way to suppress the non-reproducibility of the ORBIT we have to convince the SNS team to adopt this change at least as an option. The Giuliano SC Benchmarking effort is in full swing and should also be finished by the end of the year. Routine noise evaluation: To this end I would like to ask all PTC-ORBIT users to add the (0, 0, 0, 0, 0, 0) to their distribution in particular for long runs. In this way one would have a continuous check for the maximum PIC noise. 8/29/2013

5. SC-25 FS5 SYNERGIA Problems I We are actively collaborating with James Amundson/Eric Stern to get SYNERGIA as an alternative PIC code ready for our machines at CERN. To this end all, missing features are being added as fringe fields, time varying fields and double RF system. ➔ need to provide examples for them. The code is very conveniently to use and happens to be 5 times faster for the SIS18 case. They have a MAD-X parser but I have noticed that it does not yet work by default, e.g. for the PS. This is fixed by now. Just recently we have discovered that the dispersion but most prominently the chromaticity comes out incorrectly for the PS case. This is a CHEF problem that is being investigated and the combined function element has been identified as the cause of this issue. I am sure that Leo and myself will fix this soonest. 8/29/2013

6. SC-25 FS6 SYNERGIA Problems II They have discovered a peculiar problem for the SIS18 where a large amount of particles abruptly leave the bucket. This problem is related to the fact that they introduce their SC kicks in a very symmetric way. The problems goes away for very large number of SC kicks (not practical!) or for “magic” numbers of SC kicks per betatron period. ➔ Needs to be understood and fixed & does this exist in ORBIT? Unfortunately, this code suffers from the same non-reproducibility as ORBIT as they are using standard MPI tools. 8/29/2013

7. SC-25 FS7 SYNERGIA Plan Full Benchmarking of all CHEF features needed for CERN machines. Finish the Giuliano SC Benchmarking by the end of the year. Interesting enough they recently found that they can do the exact thing that Giuliano was using in his benchmarking with Micromap since they can easily produce a fake cavity. Contrary to PTC-ORBIT, they are using very little of the NormalForm tools that are available in CHEF. A first serious SYNERGIA release is planned for the end of the year, hopefully with all the above and a manual! 8/29/2013

8. SC-25 FS8 Micromap During my stay at GSI Giuliano and myself have been benchmarking Micromap with MAD-X. Some improvement concerning feeddown in the calculation of the linear optics have been introduced into his code. As a result we have found that all Twiss terms including the dispersion came out just fine. However, the chromaticity deviates by 16% from the correct value as found by MAD-X. This could be identified as a result of using the expanded Hamiltonian instead of the exact one as in MAD-X. Another way of saying is that MICROMAP ignores the second order terms. After this benchmarking Micromap starts to better predict the experimental results of the PS. However, it remains to be seen how serious the chromaticity issue is. 8/29/2013

9. SC-25 FS9 MAD-X with Frozen Space Charge At Fermilab in collaboration with Valery Kapin we have intoduce a frozen but adaptive SC model into MAD-X version 5 from 2011. This tool allows the adiabatic switching on of SC in the set-up phase. During the run non-linear elements, phase trombones and the cavity voltage can be varied. The Twiss parameters and the emittance/sigma re-calculation can be done as often as every turn or after any other tune interval. In the meantime this feature has been fully added to the latest MAD-X by the help of Laurent and Yngve. During my stay at BNL the code had to survive a real world example and needed modifications. In particular the exception handling had to be substantially improved (division by zero, NaN detection etc). They also needed real BB elements together with the SC elements. Lastly, a serious effort has been started at BNL to introduce MPI for a speed-up that we have calculated to be of the order of 5. 8/29/2013