1 / 13

1 st Study of Tracker Misalignments with G4MICE

1 st Study of Tracker Misalignments with G4MICE. David Forrest University of Glasgow. Scope. G4MICE Simulations (No digitisation or reconstruction - - yet!) Step VI, 1000 events, 7 beams: 0.5, 1.5, 2.5, 4, 6, 8, 10 pi mm mrad Second tracker only one misaligned

jensen
Download Presentation

1 st Study of Tracker Misalignments with G4MICE

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. 1st Study of Tracker Misalignments with G4MICE David Forrest University of Glasgow

  2. Scope • G4MICE Simulations (No digitisation or reconstruction - - yet!) • Step VI, 1000 events, 7 beams: 0.5, 1.5, 2.5, 4, 6, 8, 10 pi mm mrad • Second tracker only one misaligned • ±10 mm, ±3mrad, ±10mm & ±3mrad together, for x and y • Partially intended as training exercise

  3. Baseline Change in Emittance (p mm mrad) Input Emittance (p mm mrad)

  4. 10 p mm mrad (translation) Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Position in MICE (mm) Position in MICE (mm)

  5. 10 p mm mrad (rotation) Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Position in MICE (mm) Position in MICE (mm)

  6. 10 p mm mrad (translation+rotation) Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Position in MICE (mm) Position in MICE (mm)

  7. Effect of Misalignment (translation) on Emittance Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Input Emittance (p mm mrad) Input Emittance (p mm mrad)

  8. Effect of Misalignment (rotation) on Emittance Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Input Emittance (p mm mrad) Input Emittance (p mm mrad)

  9. Effect of Misalignment (translation & rotation) on Emittance Change in Emittance (p mm mrad) Change in Emittance (p mm mrad) Input Emittance (p mm mrad) Input Emittance (p mm mrad)

  10. Discussion • We are clearly dominated by poor statistics. The effect is less than the uncertainty. • I don’t yet know how to calculate the error of emittance except for simplistic Poisson argument: • 103 events -> 3% error. • Need to increase number of events: 104 events -> 1%; 106 events -> 0.1% error • Real error should be larger than simple statistics. Is there a G4MICE tool for calculating error in emittance?

  11. Discussion • We need the alignment to be a negligible error in the total emittance measurement • If the goal is to measure emittance with 1% precision then the error in the alignment needs to contribute ~0.1% for it to be negligible. • So, goal of alignment study is to achieve 0.1% precision, therefore we should generate 106 events per beam → we need the Grid!

  12. Future Work • Early work, seek to augment through greater attention to:Statistics (GRID)ReconstructionNext steps: Change in B field of spectrometers

More Related