Integrating solenoid field maps in PLACET Yngve Inntjore Levinsen - PowerPoint PPT Presentation

Integrating solenoid field maps in PLACET Yngve Inntjore Levinsen Barbara Dalena Rogelio Tomás Garcia CERN 11. of May, 2012

Introduction Solenoid field maps in ASCII input format Integrate with lattice and track using symplectic integrator Integration of code into PLACET 2 / 10

Input r z B r B z [cm] [cm] [G] [G] Current input format given above r redundant? r = z tan ( xangle ) Input format/units should be fixed 3 / 10

Example Field Map 4 500 400 3 300 B z [T] B r [G] B z 2 B r 200 1 100 0 0 -8 -7 -6 -5 -4 -3 -2 -1 0 Dist. from IP [m] 4 / 10

Implementation New class DetectorSolenoid defined Holds information about the field map Holds coordinate transforms between reference systems New class IRTracking defined Contains all other information about tracking procedure 2nd and 4th order symplectic integrator available All elements in BDS need new function GetMagneticField() defined Werner Herr, Num. Methods 3rd lecture 5 / 10

Implementation Example: ... TestIntRegion -beam beam1 -emitt_file emitt.dat -angle 0.001 -step 0.005 -synrad 1 -filename ildantinobuck.txt New tracking method TestIntRegion defined. z=0 in map assumed at end of beamline. If solenoid map does not cover the full length of the beamline, field assumed to be 0 elsewhere. Not available in existing tracking methods, TestFreeCorrection, TestSimpleCorrection... 6 / 10

Implementation - Suggested Alternative In principle, this is just a new step function Could instead be implemented directly into elements If solenoid map available, simply switch step function inside element 7 / 10

Implementation - Suggested Alternative In principle, this is just a new step function Could instead be implemented directly into elements If solenoid map available, simply switch step function inside element Would make solenoid field available with existing tracking methods 7 / 10

Implementation - Suggested Alternative In principle, this is just a new step function Could instead be implemented directly into elements If solenoid map available, simply switch step function inside element Would make solenoid field available with existing tracking methods Existing implementation ~700 lines, nearly finished debugging Less rewrite of original code Took a few weeks to implement&debug 7 / 10

Implementation - Suggested Alternative In principle, this is just a new step function Could instead be implemented directly into elements If solenoid map available, simply switch step function inside element Would make solenoid field available with existing tracking methods Existing implementation ~700 lines, nearly finished debugging Less rewrite of original code Took a few weeks to implement&debug Implementation requires careful debugging; coordinate system transformations & sign conventions Expect order of 1-2 weeks to write&debug this implementation 7 / 10

Simulation Example Aim: Study the effect of synchrotron radiation from solenoid field Need to subtract effects from non-optimized BDS, synchrotron radiation of other elements 8 / 10

Simulation Example Aim: Study the effect of synchrotron radiation from solenoid field Need to subtract effects from non-optimized BDS, synchrotron radiation of other elements Procedure: Track electrons through without solenoid field or synchrotron radiation 8 / 10

Simulation Example Aim: Study the effect of synchrotron radiation from solenoid field Need to subtract effects from non-optimized BDS, synchrotron radiation of other elements Procedure: Track electrons through without solenoid field or synchrotron radiation Flip distribution to positrons Track positrons backwards with solenoid field but without synchrotron radiation 8 / 10

Simulation Example Aim: Study the effect of synchrotron radiation from solenoid field Need to subtract effects from non-optimized BDS, synchrotron radiation of other elements Procedure: Track electrons through without solenoid field or synchrotron radiation Flip distribution to positrons Track positrons backwards with solenoid field but without synchrotron radiation Flip distribution to electrons Track electrons forwards through the beamline with solenoid field & synchrotron radiation 8 / 10

Simulation Example 50 first back w/sol w/sol&synrad 0 -50 y [µm] -100 -150 -200 -250 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 Dist. from IP [m] 9 / 10

50 first back w/sol w/sol&synrad Simulation Example 0 9 / 10 -50 y [µm] -100 -150 -200 -250 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 Dist. from IP [m]

Summary Solenoid implementation soon ready, mostly debugged. Alternative implementation has been suggested Would provide some added functionality Would probably be easier to maintain Time estimate ~week, expect some time for debugging Should decide on input format, sign convention, & units 10 / 10