1 / 13

Exclusive semileptonic decays at 4170 MeV

Exclusive semileptonic decays at 4170 MeV. The big picture. We have looked at 6 semileptonic decay modes. By summing all the modes, we have: B (D s +  X e + n e ) Excl = (6.147 ± 0.438 ± 0.172)%.

wray
Download Presentation

Exclusive semileptonic decays at 4170 MeV

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. Exclusive semileptonic decays at 4170 MeV

  2. The big picture We have looked at 6 semileptonic decay modes By summing all the modes, we have: B(Ds+ X e+ne) Excl = (6.147 ± 0.438 ± 0.172)% By using, t(Ds) = (500 ±7) 10-5s (PDG 07) and G(D+ Xe+n) = (0.1551 ± 0.020) ps-1 ,we have B(Ds  Xen) = (7.76 ± 0.15)% So, there is ~20% difference. Exclusive Semiletponic et. al.

  3. To tackle the problem • Look at any possible sub-structure that we may have overlooked in the modes that we were using. • Look at more possible semileptonic decays. • Understand the electron efficiency. Exclusive Semiletponic et. al.

  4. Looking at any possible sub-structures Exclusive Semiletponic et. al.

  5. Ds→ KK en MM2 (GeV2) M KK (GeV) Exclusive Semiletponic et. al.

  6. Ds→ pp en Mpp (GeV) MM2 (GeV2) MM2 (GeV2) Exclusive Semiletponic et. al.

  7. Ds+  ppp0 e+ne Exclusive Semiletponic et. al.

  8. From the tag invariant mass signal region MM2 (GeV2) MHad (GeV) Exclusive Semiletponic et. al.

  9. From the tag invariant mass sideband region MM2 (GeV2) MHad (GeV) Exclusive Semiletponic et. al.

  10. Electron ID efficiency • We will get the efficiency from radiative Bhabha events (eeg), previous criteria were (D+/0→ Xen, CBX 05-58): • The event includes two oppositely charged tracks, and an isolated photon cluster. The total energy in the calorimeter associated with additional unmatched showers is required to be less than 100 MeV. • 1.95  Evis / Ebeam  2.1 • The photon energy ≥ 0.3 GeV Exclusive Semiletponic et. al.

  11. Variables used to select the radiative Bhabha events [1] (GeV) The total energy in the calorimeter not matched to a track subtracted by the largest energy unmatched shower. Exclusive Semiletponic et. al.

  12. Variables used to select the radiative Bhabha events [2] EVis = Total Energy of the charged tracks combined with the neutrals Exclusive Semiletponic et. al.

  13. Variables used to select the radiative Bhabha events [3] (GeV) EGam1 = largest energy of unmatched shower Exclusive Semiletponic et. al.

More Related