AIDA
GELINA
BRIKEN
nToF
CRIB
ISOLDE
CIRCE
nTOFCapture
DESPEC
DTAS
EDI_PSA
179Ta
CARME
StellarModelling
DCF
K40
nToF
Draft saved at 00:00:00
Fields marked with
*
are required
Entry time:
Wed Apr 2 01:41:35 2025
Author
*
:
Subject
*
:
Observe c. 2mV p to p noise with DSO ( Z_in = 50 Ohm ) c. 60us period with HF structure. DSO connected to junction box via 34-way IDC - 16x Lemo-00 adaptor. Origin of noise upstream of 4x34-way to 8x16-way Junction Box. Not microphonics from Edwards RV5 Rotary Pump. No change observed with simple ground connections between NIM bin/+/-15V PSU/Junction Box and MSL type W1 preamplifier units/vacuum chamber/support assembly. Estimate of electronic noise Pulser BNC PB-5 Amplitude 0.5V Attenuation x1 Decay time 1ms Frequency 50Hz Preamplifier RAL108 Output impedance 100 Ohm Sensitivity 20mV/MeV ( into high Z load ), 6.7mV/MeV ( into 50 Ohm load ) Amplifier EG&G Ortec 571 Input terminated by 50 Ohm Gain x1 (internal) x 1.0 (fine gain) x 50 (coarse gain ) = 50 Shaping time 0.5us MCA Amptek 8000D Input FSR 10V 12 bit ADC Nominal gain = 6.7mV/MeV x 50 = 335mV/MeV 12 bit ADC input FSR = 10V / 0.335V/MeV = 29.85MeV FSR or 7.3keV/channel dE p+n junction strip # 4 ( of 0-15 ) pulser peak centroid = 799.8 ch pulser peak width = 7.8 ch FWHM = 57 keV FWHM E p+n junction strip # 4 ( of 0-15 ) pulser peak centroid = 864.8ch pulser peak width = 3.5 ch FWHM = 26 keV FWHM E n+n Ohmic strip # 4 ( of 0-15 ) pulser peak centroid = 913.0 ch pulser peak width = 5.3 ch FWHM = 39 keV FWHM Noise estimates are probably accurate to c. 10% level.
Encoding
:
HTML
ELCode
plain
Suppress Email notification
Attachment 1:
Drop attachments here...
Draft saved at 00:00:00
ELOG V3.1.4-unknown