1 / 4

ExB Corrections for the STAR and ALICE TPCs

ExB Corrections for the STAR and ALICE TPCs. Jim Thomas 24 - February – 2011. Solve:. Microscopic Lorentz force with “Friction”. substituting:. subject to the steady state condition. yields. where B is a unit vector pointing in the direction of B.

lark
Télécharger la présentation

ExB Corrections for the STAR and ALICE TPCs

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. ExBCorrections for the STAR and ALICE TPCs Jim Thomas 24- February– 2011

  2. Solve: Microscopic Lorentz force with “Friction” substituting: subject to the steady state condition yields where B is a unit vector pointing in the direction of B. The Langevin Equation – (see Blum, Riegler and Rolandi)

  3. Simple first order equations An Example: The Case of E  Parallel to B Electric field strength cancels out! Small terms  2nd order corrections Assuming cylindrical coordinate and E = Ezand Bz >> Br or Bf

  4. Distortion Equations – related to integrals of the fields Distortion in x or y Integral over distorted field Master Equations for E or B field distortions simple linear equations with • Distortions in the TPC are directly related to integrals of the E and B fields • These solutions of the Langevin Equation are exact to 2nd order • The matrices are rotations (with a pre-factor) related to the Lorentz angle • Since rotations commute in 2 dimensions, these matrices commute with other rotations. These same equations are valid in Cylindrical Coordinates, x  r, y r *  If you have a well defined model, and good data, then the distortion can be removed with great precision

More Related