1 / 20

Offset and angle studies with Guinea-Pig  

Investigating how offset and angle scans impact luminosity using beam-beam simulation with Guinea-Pig. Results comparison for ILC and TESLA parameters, including loss analysis and potential banana effect.

lowet
Download Presentation

Offset and angle studies with Guinea-Pig  

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Offset and angle studies with Guinea-Pig   Isabell-Alissandra Melzer-Pellmann ILC tech meeting September 28th, 2006

  2. Offset and angle scanfrom TESLA TDR Luminosity drops fast with small change of offset and/or angle Results from beam-beam simulation with GUINEA-PIG from TESLA TDR TESLA parameters: sy = 5nm , qy = 12 mrad How is the luminosity change for the ILC parameters?

  3. Offset scan with ILC parameters ILC parameters: ILC 500 NOM: sy = 5.7nm ILC 500 LOW Q: sy = 3.5nm ILC 500 LARGE Y:sy = 8.1nm ILC 500 LOW P: sy = 3.8nm ILC 500 HIGH L: sy = 3.5nm ILC 1000 NOM: sy = 3.5nm ILC 1000 LOW Q: sy = 2.5nm ILC 1000 LARGE Y:sy = 7.0nm ILC 1000 LOW P: sy = 2.7nm ILC 1000 HIGH L: sy = 2.5nm Loss of luminosity falls not so steep, for Dy/sy=±1 O(30%) (TESLA: for Dy/sy=±1 O(40%))

  4. Offset scan with ILC parameters Line for no beam-beam interaction added: L/Lnom=exp(1/4 ·(Dy/sy)2) -> strange that it is lower than the LargeY curve with beam-beam interaction… Loss of luminosity falls not so steep, for Dy/sy=±1 O(25%) (TESLA: for Dy/sy=±1 O(40%))

  5. Angle scan with ILC parameters ILC parameters: ILC 500 NOM: qy = 14.3mrad ILC 500 LOW Q: qy = 17.5mrad ILC 500 LARGE Y:qy = 20.2mrad ILC 500 LOW P: qy = 18.9mrad ILC 500 HIGH L: qy = 17.5mrad ILC 1000 NOM: qy = 11.7mrad ILC 1000 LOW Q: qy = 12.4mrad ILC 1000 LARGE Y:qy = 11.7mrad ILC 1000 LOW P: qy = 13.4mrad ILC 1000 HIGH L: qy = 12.4mrad

  6. Angle scan with ILC parameters ILC parameters: ILC 500 NOM: qy = 14.3mrad ILC 500 LOW Q: qy = 17.5mrad ILC 500 LARGE Y:qy = 20.2mrad ILC 500 LOW P: qy = 18.9mrad ILC 500 HIGH L: qy = 17.5mrad ILC 1000 NOM: qy = 11.7mrad ILC 1000 LOW Q: qy = 12.4mrad ILC 1000 LARGE Y:qy = 11.7mrad ILC 1000 LOW P: qy = 13.4mrad ILC 1000 HIGH L: qy = 12.4mrad Only 10% loss for LOW Q option, largest loss of 40% for LARGE Y option!

  7. Next step: include ‘banana effect’ Banana effect: internal bunch deformations, induced by single-bunch wakefields in the linac. TESLA TDR: single bunch correlated emittance growth expected to be 6% in average. Results from beam-beam simulation with GUINEA-PIG from TESLA TDR

  8. Next step: include ‘banana effect’ • For these plots a ‘banana shape’ beam needs to be feeded into Guinea-Pig • Simulated ‘banana’ from MERLIN not yet available. • Idea: just generate beam with ILC parameters • and change it linearly by average of 6% (number from TESLA TDR) Examples: Beam for ILC-NOM-500 Beam for ILC-NOM-500 with 100% correlated emittance growth (to make the effect visible) y/mm y/mm 100% off @ 1sY 0 @ 1sz z/mm z/mm

  9. Offset scan followed by angle scan for best offset value

  10. Offset scan followed by angle scan for best offset value

  11. Offset scan followed by angle scan for best offset value

  12. Offset scan followed by angle scan for best offset value

  13. Offset scan followed by angle scan for best offset value

  14. Offset scan followed by angle scan for best offset value

  15. Conclusion • Offset scan has similar effect for all parameter sets • Angle scan has smallest effect on LOWQ and largest effect on • LARGEY parameter sets. • Effect of wake fields causing banana deformation in beams is less • pronounced for the ILC parameters than for the TESLA parameters • (so far just tested with linear correlated emittance growth) • Possibility to get 100% luminosity for all parameter sets • when performing an offset scan followed by an angle scan • TO DO: • Feed more realistic banana beam (e.g. output from Merlin when • available) into Guinea-Pig

  16. BACKUP transparencies

  17. Offset scan followed by angle scan for best offset value

  18. Offset scan followed by angle scan for best offset value

  19. Offset scan followed by angle scan for best offset value

  20. Offset scan followed by angle scan for best offset value

More Related