1 / 12

PREx detectors

PREx detectors. Progress report. Krishna Kumar Keith Otis UMass. Piotr Decowski Selamnesh Nida Smith College. Collaboration Meeting, May 17-18,2007. HRS focal plane. Keith Otis, UMass. Thin detector:. Requirements: Integrating Radiation hard (~1 GHz) Good resolution (<25%)

gshane
Download Presentation

PREx detectors

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. PREx detectors Progress report Krishna Kumar Keith Otis UMass Piotr Decowski Selamnesh Nida Smith College Collaboration Meeting, May 17-18,2007

  2. HRS focal plane Keith Otis, UMass

  3. Thin detector: Requirements: Integrating Radiation hard (~1 GHz) Good resolution (<25%) Small size

  4. Challenges: Relative error: PM output signal per one electron passing the detector: Simulations Binominal distribution Relative statistical error of the parity violating asymmetry: To minimize we have to maximize and For we need

  5. However: For ( ) and expected rate of electrons ~1 GHz, the current at the PM output will be: We need a very low gain, linear tube!

  6. Thin Quartz Detector Concept: 15 cm conical mirror 4 cm*4cm 2” & 3” PM quartz tube mirror Optimization: -- cone length (mirror angle) -- quartz thickness -- quartz position in the cone -- PM diameter (2” and 3”) Electron energy 850 MeV

  7. Cone length (5 mm quartz) 39 d=2mm d=10mm d=5mm 2 inch PM d=5mm d=2mm d=10mm .162 6 cm 6 cm Optimal choice: 2 inch PM, 6 cm cone, d = 2 mm Number of photons reaching PM Relative width of distributions Cone length (cm) Cone length (cm) 50 3 inch PM .14 7 cm 7 cm

  8. Quartz thickness 4 mm 15 mm onset of showering 3 inch PM rms of full distribution Optimal choice: 5 mm quartz block Relative width of distribution Average number of photons at PM 2 inch PM peak width 5 mm 5 mm Quartz thickness (mm)

  9. Optimal detector parameters: Trapezoidal quartz block 0.5cm thick, 4cm*4cm upper surface Cone mirror 6 cm long, with quartz block positioned at the smaller opening of the cone 2 inch diameter PM The design is robust - the resolution does not depend strongly on design parameters as well as condition of quartz surface (as a matter of fact, more rough surface improves resolution by ~1%) Simulated performance: NPh ~ 40, NPh ~ 17%

  10. Design concept Tube mirror Cone mirror to PM

  11. Realization Front tube Quartz Quartz holder Cone

  12. Plans Thin detector: • Drawings of the detector parts are in an advanced stage • Two prototypes will be built during this summer • First beam tests planned for fall 2007 (in the Moller target area) Stack detector: • 4 - 5 quartz blocks 0.5cm - 1cm thick separated by tungsten radiator • Simulations of optimal design (in progress) Important issue: choice of proper photon detector for high intensity runs

More Related