1. Beam based modelling Beam based modelling Tobias Persson Jonne Moeskops Mattias Fjellstrom Jaime Coello de Portugal Ghislain Roy Agnieszka Szczotka Piotr Skowroński 10 Mar 2015 Beam Based Model 1

2. Online Model is quite a fuzzy term  different people mean different things:  Optics uploader to LSA and its verifications  Use of the model for beam measurements and setup  Online monitoring of the measured machine parameters and online comparison with the model to spot and study the differences  aiming at improving the model  Combinations of the above 10 Mar 2015 Beam Based Model 2

3. Result of our survey The first priorities The Predictor Tool: an application that allows checking effects of arbitrary setting changes (what happens if we change …)  GUI letting easily changing arbitrary machine parameters/knobs and displaying of the expected optics changes  It requires: Extraction of optics, orbit and optics measurements (dispersion, beta beat) Orbit and optics modelling (the effective model)  adapting the model to reproduce the measured orbit and optical parameters Extraction of power converter settings Knobs extraction and simulation so they can be tested before setting in the machine Later include more subtle data like misalignments, magnetic errors, etc. Revival of Aperture Meter 10 Mar 2015 Beam Based Model 3

4. The picture 10 Mar 2015 Beam Based Model 4 Machine settings Converter(s) Optics Measurements the model MADX scripts Twiss files Strength files Optics modelling predictions model dependent measurements MD studies Tools for Improving the model Tools for Beam orbit Misalignments Magnetic Errors Nominal Optics Orbit modelling

5. Needed Tooling 1.The aperture meter revival and its maintenance 2.Inputs for model creation:  Nominal optics from LSA (directly strength files)  Orbit  Knobs  Circuits Settings  Circuit Currents to strength converter(s)  Misalignments  Magnet errors  Beta-Beat Measurements from LSA  Other relevant measurements 3.Orbit and optics modelling 4.GUI(s) for optics visualization and analysis flow control 5.Tool to check effects of setting/knob changes 6.Model improvements and studies 10 Mar 2015 Beam Based Model 5

6. Strategy: modular approach In order to gain maximum flexibility and to provide possibility for batch analyses each component is implemented as a command line tool Data exchanged via TFS tables (files) Can use the components stand-alone, for example  The optics extractor lets finding very quickly the exact state of the machine during an MD Bootstrapping the model for analyses (f.g. MDs data) Fast to integrate with other applications, for exmple  JMad  Aperture Meter Integration done through libraries (Java packages). 10 Mar 2015 Beam Based Model 6

7. So far Optics, orbit, knobs and circuits extractor (Tobias and Jonne) Orbit modelling (Mattias) GUI/The predictor tool – first version (Jaime) Aperture Meter revived (Piotr) All the presented tools are made available on our AFS space /afs/cern.ch/eng/lhc_online_model/ where all the software is setup (including the examples) 10 Mar 2015 Beam Based Model 7

8. Optics and orbit extractor lhcmodel/lhcmodelextractor Started from YASP orbit extractor  accsoft-steering-logging-extractor-gui Added command line options, but preserving the GUI functionality Optics  For a given date it finds optics ID in the databases  Creates modifiers.madx with links to appropriate modifier files on AFS  Generates a ready to use job.LHCBx.twiss.madx MADX script from a template Template can be user defined 10 Mar 2015 Beam Based Model 8 Tobias Persson Jonne Moeskops

9. Optics and orbit extractor List of concrete examples is on our web page and in Examples file  Extract optics and orbit from timber and lsa to create a Madx script for beam 1, write output files to directory./madxextract/ lhc-model-extractor.sh -e "2012-08-24 09:00:00" B1  Extract beam orbits between 2 timestamps in 1 minute intervals and writes them to directory./beamorbits/ lhc-model-extractor.sh -oe -time "2012-09-01 11:00:00" "2012-09-01 11:02:00" 00 01 00 -p beamorbits/  Extract beam orbits between begin of RAMP and end of STABLE every 30 minutes for fill 3000 lhc-model-extractor.sh -oe -fill 3000 ramp stable 00 30 00 10 Mar 2015 Beam Based Model 9 Tobias Persson Jonne Moeskops

10. Optics and orbit extractor ItoK feature: power converter values  This feature allows us to read (for example) MQT’s settings and follow tune FB action  Nota bene, this is the only way to know MQT values Orbit correctors settings  Revived tool from Marek Strzelczyk and Gabriel Mueller  Reads the circuits currents for the magnets from the logging DB  Asks LSA to convert them to K  Pass the names via file with the list (MAD or PC names accepted)  There are lists of circuits predefined : let us know what lists are interesting for you lhc-model-extractor.sh -e "2012-08-24 09:00:00" B1 -ItoK list CORR,MQT” lhc-model-extractor.sh -e "2012-08-24 09:00:00" B1 -ItoK file "powerconverters.txt" 10 Mar 2015 Beam Based Model 10 Tobias Persson Jonne Moeskops

11. Optics and orbit extractor Knobs definitions and their values at a the requested time  Implementation was not trivial, because Knobs setting is logged with time from the beam process start One has to determine first the active beam process at a time (from LSA) and its activation time (the logging DB) lhc-model-extractor.sh -e "2012-08-24 22:55:00" B1 -K "LHCBEAM/IP1-SEP-H-MM, LHCBEAM/IP2-SEP-H-MM” 10 Mar 2015 Beam Based Model 11 Tobias Persson Jonne Moeskops

12. Orbit modeling lhcmodel/virtualcorrectors Orbit modeling performed by MADX SVD orbit correction tool  Provides a script to install virtual correctors at each quadrupole magnet  Orbit correction finds their setting to reproduce the extracted orbit  Saves the setting to a file 10 Mar 2015 Beam Based Model 12 Mattias Fjellstrom

13. Orbit modeling In general very good agreement with measurements. Single command examples at /afs/cern.ch/eng/lhc_online_model/virtualcorrectors/ ExampleX (where X is a number) 10 Mar 2015 Beam Based Model 13 Mattias Fjellstrom

14. GUI / Predictor tool Based on the Beta-Beating application /afs/cern.ch/eng/lhc_online_model/pro/bin/ gui_bb.v_pro.sh gui_bb.v_next.sh Choose where to place the model and MADX binary 10 Mar 2015 Beam Based Model 14 Jaime Coello de Portugal

15. GUI / Predictor tool Importing optics 10 Mar 2015 Beam Based Model 15 Jaime Coello de Portugal

16. GUI based on beta beating app. The steering panel Commands can be passed to MADX manually using the input window at the bottom 10 Mar 2015 Beam Based Model 16 Jaime Coello de Portugal

17. GUI / Predictor tool Filter allowing fast access to the model variables 10 Mar 2015 Beam Based Model 17 Jaime Coello de Portugal

18. GUI / Predictor tool Plotting of selected models 10 Mar 2015 Beam Based Model 18 Jaime Coello de Portugal

19. GUI / Predictor tool Beta-beating with respect to selected model. 10 Mar 2015 Beam Based Model 19 Jaime Coello de Portugal

20. GUI / Predictor tool Adding additional effects  Orbit modelling 10 Mar 2015 Beam Based Model 20 Jaime Coello de Portugal

21. GUI / Predictor tool Adding additional effects  Simulate a knob action Find a knob 10 Mar 2015 Beam Based Model 21 Jaime Coello de Portugal

22. GUI / Predictor tool Adding additional effects  Simulate a knob action Here, effect of a beta beating correction knob 10 Mar 2015 Beam Based Model 22 Jaime Coello de Portugal

23. GUI / Predictor tool The models and output files are left in the directory and can be further modified and analyzed manually All the steps can be done without clicking in the GUI, and be wrapped into a small shell script 10 Mar 2015 Beam Based Model 23

24. Sector tests: the first experience Aperture measurements 10 Mar 2015 Beam Based Model 24

25. Sector tests: the first experience Aperture measurements 10 Mar 2015 Beam Based Model 25

26. Sector tests: the first experience Aperture measurements 10 Mar 2015 Beam Based Model 26

27. Sector tests: the first experience Aperture measurements The scanned aperture  All recorded beam traces with 3 sigma envelope 10 Mar 2015 Beam Based Model 27 Above physical aperture BPM readings due to non-linearities and poor resolution for low bunch charge

28. Sector tests: the first experience Polarity measurements GUI and Orbit modeling  The integrated orbit modelling tool 10 Mar 2015 Beam Based Model 28 Display of the extracted and the modelled orbit

29. Sector tests: the first experience Polarity measurements kqtl11.r2b1  Red: model orbit response to kick with correct polarity  Blue: the same with reversed polarity  Black: measured orbit Conclusion: black closer to red, polarity is good  minus the offset in s 10 Mar 2015 Beam Based Model 29

30. Sector tests: the first experience Lessons learnt The tools showed to be useful The GUI needs to be made more intuitive Better annotation of the data (beam No, date, effects included) Easier comparison with the measurements Additional tool for plot manipulations would be off hand  For example, for polarity checks we needed to compare difference of orbits between 2 models (no problem, this is in) with difference between 2 measured orbits 10 Mar 2015 Beam Based Model 30

31. 10 Mar 2015 Beam Based Model 31 Web page http://lhcmodel.web.cern.ch

32. Other Inputs for Model Creation Misalignments and Magnetic Errors  Currently implemented in WISE  Data extraction currently not automatic  Is it worth re-writing it as a Java/console version? 10 Mar 2015 Beam Based Model 32

33. Conclusions Aperture meter operational Automatic data extraction for optics, orbit, knobs and circuit settings, plus conversion to MADX format Orbit modelling First version of the prediction tool / the model GUI First successful practical usage during the sector tests 10 Mar 2015 Beam Based Model 33

34. Outlook Extraction of the measured beam parameters and errors Optics modelling GUI improvements  Creation of a model from a beam process Useful for an MD preparatory studies  Re-opening of a model from disk  user interface improvements We will follow the commissioning & MDs analyzing all the available data to validate the model  Prove its accuracy  Optimize the algorithms  Look for systematic effects indicating misalignments or errors 10 Mar 2015 Beam Based Model 34

35. The END 10 Mar 2015 Beam Based Model 35 Not really, just the beginning… We will be happy to hear about any ideas for application of the beam-based model

36. The scope Provide more detailed machine model that accounts for all dynamical information available in the control system  For example orbit or implemented corrections  For a given moment in past as well as “on-line” Applications  To check effects of settings changes What happens if – prediction tool  To provide data for model-based measurements For example beta beating or aperture measurements  Verify the accuracy of the model against measurements Study the available data to validate the beam based model and look for systematic effects 10 Mar 2015 Beam Based Model 36

37. Next steps Tools for model improvements Comparing model continuously will show when it deviates from reality Application to monitor and compare with model  Tune  Chroma  Orbit Functionality to compare the model with more sophisticated measurements, f.g. beta-beating  Phases  Beta  Dispersion Feed-backs action studies  Orbit  Tune Corrections  Linear  Non-linear 10 Mar 2015 Beam Based Model 37  Bumps  Crossing angles  Aperture (losses)  Tune  Coupling  Chromaticity

38. The codes Java codes naturally use the CO framework including the SVN For other codes lhcmodel SVN repository was setup  MADX scripts  The copy of the LHC model itself So we can add improvements that we need  Other programs  Scripts that glue it all together and allow easy single command execution 10 Mar 2015 Beam Based Model 38

39. pre-existing Packages Applications  accsoft-om-app-apperturemeter  accsoft-om-app-bpscan  accsoft-om-app-chroma  accsoft-om-app-dataextraction  accsoft-om-app-measurementanalyzer Underlying libraries  accsoft-om-core  accsoft-om-domain  accsoft-om-gui  accsoft-om-jmad-online-service  accsoft-om-logging  accsoft-om-lsa  accsoft-om-manager  accsoft-om-math  accsoft-om-measurements  accsoft-om-server  accsoft-om-util 10 Mar 2015 Beam Based Model 39 185606 lines of Java code

40. Coverage and priorities 10 Mar 2015 Beam Based Model 40 ExtractorsNamesp Nominal optics from LSA (strength files) Piotr1 Circuits SettingsPiotr3 Circuit Currents to strength converter(s) Piotr4 MisalignmentsPiotr1 OrbitTobias2  -beat meas. from LSA OMC5 Tools for setup & OPNamesp Aperture meter (modifs for sector tests - line) Piotr1 Optics visualization (with possibility to change parameters) TBD1 Beam-beam footprint9 Rematch + knob production ? Tools for model improvements-up Namesp Orbit modellingGhislain1 Feedback action studiesTobias5 Comparison of directly measured parameters (orbit, bumps, Q, Q’, Xing, aper) 2 Comparison of  -beat meas. Tobias/P.3 Corrections follow-up4 Tune modellingGhislain2 Chroma modellingGhislain