1 ROTSCINT 2 Padova - Genova collaboration PINHOLE SCINTIGRAPHY WITH ROTATING SLIT
2 PARALLEL HOLE SCINTIGRAPHY Poor spatial resolution Steady sensitivity Parallel hole collimator Scintillator Gamma source
3 Pinhole collimator Magnification Better sensitivity Parallax error Gamma source PINHOLE SCINTIGRAPHY Scintillator
4 Gamma source Rotating- slit collimator ICCD readout ICCD readout Scintillating fiber bundle ROTATING SLIT SET- UP
5 20 mm 50 mm L= 70 mm 70 mm 25 mm Effective pinhole width = 1 mm L= 50 mm 50 mm Detector resolution (mm) SPATIAL RESOLUTION (L= 70 mm) 0.5 (L= 50 mm) 1 2 Source diameter 50 mm Source diameter 25 mm ( ) 1.2 – – – 2.1 ( ) 1.4 – – 2.9 PARALLAX ERROR- FREE SPATIAL RESOLUTION
6 50 mm 20 mm 170 mm 40 mm 100 mm 15 mm LONGITUDINAL VIEW
7 Scintillating fiber plate Maximum FOV – 360 o rotation slit FOV
8 slit scintillating fiber plate FOV Minimum FOV – 180 o rotation
9 CCD FOV (70 mm diameter) Image intensifier (25 mm diameter) Fiber optics guide FOV (140 mm diameter) SCINTILLATING FIBER- PLATE READ-OUT
10 1 BACK- PROIECTION IMAGING 2 1.Rejected gamma ray 2.Detected brackground gamma ray 3.Detected gamma ray 4.Compton scattered gamma ray 5.Compton scattered gamma ray in the detector BACK-PROJECTED IMAGE [b(r)] first scan second scan third scan fourth scan
11 COMPTON REJECTION [f*(r)] = [b(r)]/ [(1/r)] f(r) + c 1 ( r ) + c 2 (r) +… 1/r b(r) f*(r)
12 MONTECARLO TEST minimum FOV 2 mm diameter sources one projection zero Compton gammas / projection projections - 1 mm slit width
13 2 mm diameter sources one projection MONTECARLO TEST minimum FOV Compton gammas / projection projections - 1 mm slit width
14 zero Compton gammas / projection projections - 1 mm slit width 2 mm diameter sources Compton gammas / projection projections - 1 mm slit width 2 mm diameter sources MONTECARLO TEST Maximum FOV
15 MONTECARLO TEST Minimum FOV – Compton structure Compton gammas / projection – 100 projections -
16 UNCLEDDED FIBERS WITH EXTRAMURAL ABSORBER (EMA) without EMA stripes of EMA statistical EMA fibers with air bubbles
17 Scintillating fibers without cladding (0.5 mm diameter) Stripes of EMA (50 100 µm thick) SELECTED UNCLADDED FIBER- PLATE 30 x 13 fibers (18 mm x 6.5 mm)
18 GAMMA SOURCE PINHOLE UNCLADDED FIBER- PLATE VS COllimated Holes CLADDED FIBER-PLATE
19 gamma source fiber plate slit ICCD camera Scintigraph-prototipe set-up
mm rotating slit X source (50 kV) Beam stopper 2 mm thick lead 1mm diameter two holes scintillating fiber rotating bundle EXPERIMENTAL SET UP 40 mm thick plastic
Restored image of two 1 mm sources (only 45° four scans)
22 Rulli in gomma dura per la tiratura della fibra. La velocità di tiratura va regolata in base al diametro della fibra Set up of the fiber- drawing plant (ing. R. Dall’Igna Staz. Sper. Vetro – Murano) Sistema di sostegno, avanzamento e rotazione della bacchetta di vetro (~ 10 giri/min) Bacchetta di vetro da 6 a 12 mm di diametro Forno di riscaldamento elettrico (crogiolo di platino) Vista dall’alto del forno Isolamento in fibra ceramica del forno Vista superiore dei rulli Alimentazione del forno con regolazione automatica della temperatura tramite termocoppia Bacchetta di vetro stirata
23 ROTSCINT 2 (Padova – Genova) Piano finanziario globale di spesa (k€) interno consumo apparati Totale Richieste servizi a Padova - Off. Elettr. : 1 M.U. - Off. Mecc.: 3 M.U.