1 / 10

Photoelectron Yield in pixel HPD

Photoelectron Yield in pixel HPD. S. Easo, Glasgow University 29-3-2000. Test beam data taken in June 1999. 80 mm HPDs with 61-pixel anodes and analogue readout. Preliminary results already presented. Experimental Setup. RICH1 setup 120 GeV/c pion beam C4F10 , air radiators

jayme-branch
Download Presentation

Photoelectron Yield in pixel HPD

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. Photoelectron Yield in pixel HPD S. Easo, Glasgow University 29-3-2000 • Test beam data taken in June 1999. • 80 mm HPDs with 61-pixel anodes and analogue readout. • Preliminary results already presented.

  2. Experimental Setup • RICH1 setup • 120 GeV/c pion beam • C4F10 , air radiators • 1117 mm focal length • mirror • Three 80 mm HPDs • Cross focussing • demagnification ~5. • This presentation: C4F10 radiator at 164 mbar and 19 degree C.

  3. Event Display Real Data :run 30040 Simulated data :run30040

  4. Event Display • Real Data :run 30040

  5. Yield from data

  6. Yield from Real Data • To estimate the signal yield: • Fit a Gaussian to the left side of the pedestal. • Using poisson statistics, (Nped = Ntot exp(- m ) • get the Mean number of photoelectrons. • To estimate the signal loss: • Remove the fitted Gaussian of the pedestal. • In the remaining spectrum, estimate the • amount below the threshold. • To estimate the background: • Detector related: from pedestal runs, • yield above threshold. • Beam related: yield in pixels outside • the Cherenkov ring.

  7. Yield from Real Data • at 114 mbar • total background • signal loss • below 4 sigma • threshold HPD1 Signal Loss below 3 sigma: 3.6 % 4 sigma: 6.1 % 5 sigma: 8.4 %

  8. Yield from Simulation • Inputs to simulation: • Refractive index of the radiator • Mirror reflectivity • Quantum efficiency of the tube, etc.

  9. Photoelectron yield MC Yield Variation HPD 1 2 3 • Main Error sources: • QE of phototube 5% variation: 0.416 0.378 0.565 • Ref. Index: different parametrization: 0.461 0.429 0.247 • Non-uniformity on photcathode : 0.065 0.273 0.220

  10. Summary • The Yield in data and simulation agree with other • It also agrees with the preliminary estimates • More data to be analyzed : high pressure runs

More Related