1 / 18

Radiative Corrections for polarized H(e,ep)

Radiative Corrections for polarized H(e,ep). Chris Crawford Mass. Inst. of Tech. Jan. 24, 2002. Introduction Higher order diagrams Hard vs. Soft photons Approximations Radiative cross section. Existing software SIMC (Hall C) MASCARAD Calculations Remaining work. Outline.

vinnie
Download Presentation

Radiative Corrections for polarized H(e,ep)

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. Radiative Corrections for polarized H(e,ep) Chris Crawford Mass. Inst. of Tech. Jan. 24, 2002

  2. Introduction Higher order diagrams Hard vs. Soft photons Approximations Radiative cross section Existing software SIMC (Hall C) MASCARAD Calculations Remaining work Outline

  3. Internal Processes Born Bremsstrahlung Vertex correction Vacuum polarization

  4. External Processes • Bremsstrahlung • Multiple scattering • Landau straggling • Energy loss • Simulate these with BLASTMC

  5. Soft Photons: within detector energy resolution E Multiple photon emission dominates at low Hard photons modify kinematics Hard v.s. Soft Photons

  6. Radiative Cross Section • Bethe & Heitler, P.R.S.L. A146, 83 (1934) • J. Schwinger, Phys. Rev. 76, 790 (1949) • Mo & Tsai, Rev. Mod. Phys. 41, 205 (1969) • Inclusive cross section • Soft photon approximation • Peaking approximation • Cutoff parameter E

  7. SIMC • R. Ent et. al., Phys.Rev.C 64 054610 (2001) • Soft photon approximation • Multiple photon emission • Two unphysical divergences

  8. SIMC • Peaking approximation • Radiation along initial, final electron • Used for applying vertex correction

  9. MASCARAD • A. Afanasev et. al., Phys.Rev.D 64, 113009 • Bardin & Shumeiko, Nucl.Phys. B127, 242 • Covariant, no cutoff parameter S.P.A. Hard Photons

  10. MASCARAD • The asymmetry is insensitive to 

  11. Phase Space • Change of variables for

  12. Coincidence • Integrate over proton acceptance A • Sharply peaked in  and k

  13. Results from MASCARAD

  14. Results from MASCARAD

  15. Results from MASCARAD

  16. Results from MASCARAD

  17. Other Methods • Reconstruction in hadronic variables • Simplifies integration • C++ code PRC, by Feng Xiong • Based on POLRAD 2.0 • Others

  18. Remaining Work • Incorporate into BLASTMC (userGen) • Use external physics of GEANT • Simulate proton acceptance • Improvements • Use peaking approx. + residual • Add arbitrary polarization angle • Simulate e-p elastic experiments • Generalize to other BLAST reactions

More Related