Solenoid effects in CLIC Yngve Inntjore Levinsen, Barbara Dalena, - PowerPoint PPT Presentation

Solenoid effects in CLIC Yngve Inntjore Levinsen, Barbara Dalena, Rogelio Tomás Garcia Linear Collider Workshop 25. October, 2012

IR Tracking in PLACET Integration of code Trajectory comparison with old code Recent results Future planning 2 / 14

IR Tracking in PLACET ... TestIntRegion -beam beam1 -emitt_file emitt.dat -angle 0.001 -step 0.005 -synrad 1 -filename ildantinobuck.txt Tracking method TestIntRegion now considered fully debugged. 4th order symplectic integrator. Example in svn, in folder examples/irtracking. Dipoles not correctly treated yet (challenging to define orbit). Not available in existing tracking methods, TestFreeCorrection, TestSimpleCorrection... 3 / 14

Code Comparison Trajectories... Horizontal trajectories Vertical trajectories 140 0 PLACET PLACET 120 Old 20 Old 100 40 80 60 x [um] y [um] 60 80 40 100 20 120 0 140 20 160 18 16 14 12 10 8 6 4 2 0 18 16 14 12 10 8 6 4 2 0 Distance from IP [m] Distance from IP [m] 4 / 14

Code Comparison Trajectories... Difference between trajectories 0.7 vertical 0.6 Difference (PLACET - Old) [nm] horizontal 0.5 0.4 0.3 0.2 0.1 0.0 0.1 18 16 14 12 10 8 6 4 2 0 Distance from IP [m] 5 / 14

Code Comparison Luminosity... Old PLACET L peak 96.7 % 95.5 % L tot 95.7 % 95.3 % Numbers are averages from several GUINEA-PIG runs. Excellent agreement between the two codes. Used map “ildantinobuck”, an old ILD map without bucking coil. 6 / 14

Preliminary Results 5 0.10 4 0.08 3 0.06 B z [T] B r [T] 2 0.04 1 0.02 0 0.00 1 0.02 5 4 3 2 1 0 5 4 3 2 1 0 Map from November 2011 (update underway) SiD with anti-solenoid. Main luminosity loss from combination of QD0-field and B r . 7 / 14

Preliminary Results Vertical Orbit 12 10 8 About 11 µ m 6 y [um] Similar to previous results 4 using old code 2 0 2 7 6 5 4 3 2 1 0 Dist from IP [m] 8 / 14

Preliminary Results Distributions at IP - only synchrotron radiation 150 150 2 10 125 125 1 5 100 100 xp [ µrad ] y [nm] 0 0 75 75 −5 −1 50 50 −10 −2 25 25 −1 1 −2 0 2 −50 0 50 y [nm] x [nm] 150 75 2 15 125 10 60 1 5 100 yp [ µrad ] y [nm] 0 0 45 75 −5 −1 30 −10 50 −15 −2 25 15 −2 −1 0 1 2 1490 1492 1494 1496 1498 1500 1502 y [nm] Energy [GeV] 9 / 14

Preliminary Results Distributions at IP - SR and Solenoid 30 30 15 −5320 10 25 25 −5330 5 −5340 20 20 xp [ µrad ] 0 y [nm] −5350 −5 15 15 −5360 −10 10 −5370 10 −15 −5380 −20 5 5 −5380 −5370 −5360 −5350 −5340 −5330 −5320 −100 −50 0 50 100 y [nm] x [nm] 30 60 −5320 0 25 50 −5330 −10 −5340 20 40 yp [ µrad ] y [nm] −5350 −20 15 30 −5360 −30 10 −5370 20 −5380 −40 5 10 −5380 −5370 −5360 −5350 −5340 −5330 −5320 1490 1492 1494 1496 1498 1500 1502 y [nm] Energy [GeV] 10 / 14

Preliminary Results Luminosity w/o solenoid w solenoid [10 34 / cm 2 / s ] [% of ideal] L peak 1.91 96.5 L tot 6.38 96.1 Better than reported last year (~14%). We found after a lot of debugging that synchrotron radiation was counted twice (+10%). 11 / 14

Preliminary Results Tuning 90 80 70 60 L/L 0 [%] 50 40 30 20 10 1 2 3 4 5 6 7 8 9 QD0 vert. pos. [um] 12 / 14

Summary Code finally gives results in excellent agreement with previous external code. Theoretical luminosity loss due to solenoid with most recent SiD map ~ 4-5 %. 13 / 14

Next Steps Tuning simulations. [started] Analyse new field maps. [underway] Misalignments of solenoid wrt beamline. 14 / 14