Differences

This shows you the differences between two versions of the page.

--- strutture:lnf:da:btf:dispositivi:rivelatori:calorimeter:calobtf2 [2024/02/07 17:37] – diociaiu@infn.it
+++ strutture:lnf:da:btf:dispositivi:rivelatori:calorimeter:calobtf2 [2024/02/07 22:26] (current) – diociaiu@infn.it
@@ Line 1: / Line 1: @@
+======CALOBTF2======
+\\
+**Lead Glass -> Cherenkov**\\
+\\
+From the former OPAL electromagnetic calorimeter\\
+**Referred measuring System**\\
+Caen V965 - CH4 900pC (new Type)\\
+Caen N625 - CH2 @ -7mV bias\\
+\\
+**N=[239.7*(x)^7.705]*Ebeam\E0** \\
+N = single particle value [adc unit, pedestal subtracted]\\
+x = V/1200 [V]\\
+V= Voltage on CALO (Minimum Voltage 450V)\\
+Ebeam = Energy beam [MeV]\\
+E0 = 450 [MeV]\\
+\\
+**TABLE @ 450 MeV**\\
+**Last calibration @450MeV 20220505**\\
+^ V     ^ N     ^
+| 1300  | 444.14   |
+| 1200  | 239.7  |
+| 1100  | 122.6|
+| 1000  | 58.83   |
+| 900   | 26.122  |
+| 800   | 10.540  |
+| 700   | 3.768   |
+| 600   | 1.1496  |
+| 500   | 0.28288 |
+**Oscilloscope to Multiplicity calibration**\\
+To recover multiplicity by your own measurement system with our CALOBTF signal, follow these steps:\\
+  * Usually we will refer our measurement with our QDC Caen V965 (new type, 900[pC] full scale in 12bit, output is in ADC values)
+  * acquire the signal in time domain
+  * give an integration time about 200[ns], centred on Beam signal (typically CALOBTF signal Tr=8[ns], Tf=20[ns]) to pick up best baseline
+  * measure integrate pedestal without beam signal (P). Oscilloscope will give you values in [V*s], to get value in [pC], divide by your input impedance.  Usually P=70/(4096x900) [ADC/ADC*pC] = 13.7 [pC]
+  * measure the integrated gate signal (GS) and removing pedestal value and get your signal (S) then [mV*ns/Ohm]=[pC]
+  * Multiplicity (M) is this value normalized in our ADC scale value, divided by N , single particle value (see table on top for CALOBTF, voltage and beam energy dependant)
+S=(GS-P)/(50)= [V*s/Ohm]\\
+M=(S/900E-12)*4096/N = [(C/C)*(ADC/ADC)] \\
+\\
+**CALO as BACKGROUND gamma detector for HIGH INTENSITY operation on N@BTF**\\
+We can use CALOBTF as background gamma detector to discover the upper limit of gamma to prevent the safety sistem to trips.\\
+We put CALOBTF in the bent middle line at 3.8 meters from exit bent pipe with 500V supply\\
+Normal operation means up to 20mV peak to peak signal, if above the safety trips\\