310 likes | 390 Views
KEK beam test. H. Sakamoto. Purpose. To optimize a concentration of the second dopant for scintillating fibers KEK beam test to study light yields for various concentrations Summary. Purpose for the beam tests. We tested the light with two difference tests
E N D
KEK beam test H. Sakamoto
Purpose • To optimize a concentration of the second dopant for scintillating fibers • KEK beam test to study light yields for various concentrations • Summary
Purpose for the beam tests • We tested the light with two difference tests to study the light yield with realistic components of 3HF concentration dependence • First time (T553-1): calibrated the gain of pmt with 1 p.e. • Second (T553-2) : 〃 with more p.e. (~20p.e.) T553 (this time) T542 (last year) • SciFi length 40cm 20cm • Mirror aluminized mirror aluminized mylar • Connection MICE connector acryl board • Clear fiber w/ and w/o 4m no • PMT R7411U-40MOD R7899-MOD
Scintillating fibers tested • Kuraray SCSF-3HF ; 0.35mm-phi, multi-clad, s-type • In this beam test, pT(2%) scifi was also tested. • pT(1%) + 3HF(5000ppm) • pT(2%) + 3HF(5000ppm) • pT(1%) + 3HF(3500ppm) • pT(1%) + 3HF(2500ppm) • pT(1%) + 3HF(4500ppm) • pT(1%) + 3HF(7500ppm) • pT(1%) + 3HF(10000ppm) • pT(2%) + 3HF(10000ppm)
Attaching SciFi with MICE conn. • Attached the SciFi and clear fibers with MICE conn. • Clear fibers for pmt’s gain calibration SciFi (0.35mmΦ): 14fibers Clear fib Clear fiber (1.05mmΦ) SciFi
Scintillating fiber • Connecting the SciFi into the hole of MICE connector
Fixing by optical cement • Fixed the SciFi with optical cement
Quantum efficiency of VLPC • 3HF emission spectrum 520nm 520nm Q.E. of VLPC & 3HF emission spectrum
Photo multiplier tube • We used the photo multiplier tube instead of VLPC. • Hamamatsu R7411U-40MOD • GaAsP (Gallium-Arsenic-Phosphorous) • 8mm diameter • 10 stage • Head-on Type • HV= -850V
22mm 20 fibers Aluminized tape Set up T542 (last year) • Side view • Front view Sci-Fi PMT PMT Sci-fi • These were in a dark box
KEK beam test set up Ⅰ TOF2 TOF1 Sci-Fi D1 D2 D3 Beam • p+ • π+ • 0.6 GeV/c • 1.2 Gev/c Dark box 1.5m 4m • Trigger • coincidence of all counters • Data we took • ADC & TDC of all counters and Sci-Fi Sci-Fi TOF2 D1 D2
Set up (T553) • Beam area Dark box
Set up (T553) • In the dark box D1 SciFi and support D2
mirror pmt SciFi Setup (T553) • SciFi and its support gide before setting in the dark box
Aluminized mirror SciFi Mirror
PMT (R7411U-40MOD) PMT SciFi
14 fibers were arranged into 420um bitch Close up of SciFi
Arrangement of Scifi • For single layer : 14 fibers 420um • For double layer : 3 fibers for up and 4 for down
T553-1 (first test) • Gain calibration -1 • calibrated the PMT’s gain by 1 p.e. • Injected the LED light adjusted as 1 p.e. to the cathode surface of the PMT. • 1 p.e. was determined with the ratio of 0 p.e. and 1 p.e. • But this measurements was not worked • Not good S/N • To the second test with higher p.e.#
T553-1 (first time) • The result : Light yield 1.5000 -1% 2. 4500 -1% 3. 10000 -1% 4. 2500 -1% 5. 5000 -2% 6. 3500 -1% 7. 7500 -1% 8. 10000 -2% • These are not p.e. but the relative values are meaningful. • 5000ppm has the highest lightyield in tested fibers.
T553-2 (second test) • Gain calibtion -2 • Adjusted the LED to about 20 p.e. • P.e.# was estimated by ((MEAN)/(RMS))^2
Beam stability • Stability of beam momentum by Time of flight of 0.6 (Gev/c) proton
Monte Carlo • Simulated 1.2 (GeV/c) data for proton and pion • Histgram (red) = MC • Plot w/ err = data Pion Proton
Result of light yield • Light yield of 5000ppm-(1%) P.e.# (estimated by MC) • Light yield (5000-1%) = 8 p.e. @MIP
Result of light yield • Light yield of 2500ppm-(1%) P.e.# (estimated by MC) • Light yield (2500-1%) = 6.5 p.e. @MIP
The result • Single layer && 4m clear fiber 5000ppm-1% 2500ppm-1%
The result • Double layer && NO clear fiber 2500ppm-1% 5000ppm-1%
The result • Double layer && 4m clear fiber 2500ppm-1% 5000ppm-1%
Conclusion from the beam test • We tested scintillating fibers of different 3HF concentration. • We used green sensitive PMTs in stead of VLPC. • The result of light yield test • Single layer • 5000ppm-1% : 8 p.e. (3 p.e.) • 2500ppm -1%: 6.5 p.e. (3 p.e.) • Double layer • 5000ppm-1%: 10 p.e (4.5 p.e.) • 2500ppm-1%: 8 p.e. (4.5 p.e.)
Summary • We studied the light yield of scintillation fibers mixed with 3HF as a secondary dopant with realistic component . • We studied the light yield with some conditions. • w/ and w/o 4m clear fiber • Single and double layer • The result of light yield • pT(1%) + 3HF(5000ppm)has the highest light yield in any conditions.