1. The E835 SCI-FI Detector
In Ferrara It has been built a scintillating fibers detector for the tracking system of exp. E835 (Charmonium spectroscopy) a fixed target experiment at the Fermilab antiproton accumulator
4 coaxial cylindrical layers of scintillating fibers:
Kuraray SCSF-3HF, R= 0.84mm, double cladding
Light signal brought to the photosensors through few
meters of clear fibers (Kuraray multiclad) of the same diameter
photosensors: VLPCs (Visible Light Photon Counters) semiconductor
devices: G ≈ 15000, Q.E. ≈ 70%, Cryo-temp: 6.5K

2. E835 SCI-FI Detector layout
Scintillating
fibers
Clear fibers
Bending radius: 5cm

3. E835 SCI-FI Detector performances
Angular Resolution
Detector Efficiency

4. Fibers quality control
Light yield (a.u.)
The detector was designed and assembled in Ferrara, main operations:
Polishing both ends of each fiber
Splicing of the scintillating fibers with the clear fibers
Sputtering (mirroring) of the not-readout end of the fiber
Quality controls on each fiber:
Light yield
Attenuation length
Light yield as a function of curvature (only on a few fibers)
Reflectivity of the mirrored end
Light loss in the splicing point
R (cm)
Light yield vs bending radius
Light yield loss in
the splicing point
Reflectivity of the
mirrored end

5. summary
Expertise in Ferrara about building, handling, QC operations of fiber detectors
Facility in Ferrara for Quality Control of fibers