V0L Hardware Status

1
V0L Hardware Status

• ALICE WEEK
• CERN, MARCH 2003

Ana Delia Becerril IFUNAM, México.
2
Outline

• V0 Detector.
• V0L Proposed Detector Assembly.
• Megatile Technique.
• V0L Prototype.
• Experimental Setup.
• Results from Tests.
• Conclusion

3
V0 Detector

• Zero level trigger system for ALICE.
• Made of two arrays of scintillating counters, V0R
  (IPNL) and V0L (Mexico).
• Two centrality triggers (Pb-Pb reaction) .
• Multiplicity indicator.
• Control of the luminosity.
• Validation signal for the dimuon trigger.

4
V0L. Proposed Detector Assembly

• Axially simetric thin plastic scintillator.
• R min43 mm. R max445 mm.
• Located at 3500 mm to the left of vertex
  position.
• Covers ? -5.1 to ? -2.8.
• 72 pixels in 5 rings.

5
The Megatile Techique

• One single piece of scintillator.
• Half way machined grooves, filled with white
  epoxy.
• Both faces of scint.
• Radial grooves for WLS fibers.

6
Embedded WLS fiber
7
V0L prototype

• Made with the Megatile technique.
• BC408 plastic scintillator.
• Y11 and BCF92 WLS fibers tested.
• Teflon and Aluminum wrappings tested.
• Prototype tested in September 2002 at the PS
  accelerator at CERN.

8
Experimental Setup

• PMT Philips XP2020.
• 7 GeV/c pions beam.

9
Results from Tests
Single photoelectron calibration.
Counts
Channel
Light collection from MIPs Element of ring 2,
with 3 Y11 WLS fibers and Al reflector.
10
Light yield
11
Number of p.e.
12
(No Transcript)
13
Conclusion

• A prototype of V0L was built using the Megatile
  technique.
• A reasonable light collection can be achieved
  with this design.
• In order to increase the light collection, we
  need to improve our design.
• On the basis of this test, we consider that a
  design based on this technique can fullfil the
  requirements for the V0 system.