Hands-on Activities
1. Act#1 (2.75h, Mon. Mar.4):
Safety rules, lab arrangement (group allocation, soldering station…), hardware components (oscilloscope, multimeter…)
Spend significance time to practice with oscilloscope and function generator or the like (create an electric (analog) signal with defined frequency, amplitude, width, rise and fall time and see the record from oscilloscope)
LED driving with function generator or the like (at which frequency you can't see the light pulses in discrete pattern; at with amplitude you can't see the light)
Introduce photosensor and how to work with it
Group A: Single MPPC, can use a working readout board to see the signal with dark noise; observe the distinguish between 1 PE, 2PE.. and signal with LED. Try to see at the level where you can't see by your eye but can see with sensor
Group B: MPPC array, check the voltage operation in the board, quickly check the signals from various channels (try all 16 channels and notice the (non-)uniformity in the response); observe 1PE, 2PE…
Group C: Light tightening; and get the PMT signal; adjust the operation voltage and gain control
2. Act #2 (1.5h, Tue. Mar.5)
Making the circuit to work with MPPC (group A and C), LED driving with function generator. Observe signal from sensor with various configuration (intensity, frequency, pulse width..)
Group A
Two students go for circuit soldering, the other try to setup and understand functionalities of oscilloscope, control LED/ Nanobeacon
Understand the concept of signal coincidence/ difference between using the NIM modules and oscilloscope
Group B
Measure the noise rate, electric gain (channel-by-channel uniformity)
Check the coincidence with two and three channels, referring to the estimated muon rate to come up with a reasonable trigger pattern (to attain relatively high signal-to-ratio)
Group C
3. Act #3 (1.75h, Tue. Mar.5):
Group A Test the soldered circuits, noise suppression, noise rate, coincidence rate…(estimate the muon rate on the scintillator and use it for reference)
Group-B Optical cross-talk check: shining LED in a specific channel and check the signal of the nearby channels. Justify whether this cross-talk is significant or not.
Group-C LED driving with Analog discovery (software is on the allocated PC); PMT signal vs MPPC signals: check detection efficiency, dynamic range, linearity
4. Act #4 (1.75h, Wed. Mar. 6):
Group A: setup and measure the speed of light in the optical fiber (convert from timing to distance; refer to the refractive index of the optical fiber)
Group B: setup and measure the profile of a light source (eg. from LED transport through an optical fiber. Refer to the so-called numerical aperture of the fiber )
Group C: Setup and measure the spectra of the light source with optical filters
5. Act #5 (1.75h, Thu. Mar. 7):
Work in combination of Scintillator, wavelength shifting fiber and photosensor; concept of muon counter; NIM modules to use: discriminator, scaler, coincidence (and delay if needed)
Group A use scintillator bar; wavelength shifting fiber polishing and glue to be fitted in the optical connector to single MPPC
Group B use laser-cutted plate for coupling wavelength shifting fiber to sensor.
Group C use scintillator cube; observe signal; check the rate; compare the signal with wavelength shifting fiber
6. Act #6 (2.0h, Thu. Mar. 7):
Check the coincidence rate of muons and see whether it is consistent with what we expect. Try to tighten or loosen the threshold in the trigger pattern and see how the result changed.
Learn how to use DAQ program for automate data taking
Analyze the data. Depend on the group members to decide which programing language and data format to use.
7. Act #7 (2.75h, Fri. Mar. 8):
Cosmic ray muon data taking and analysis
8. Act #8 (2.75h, Fri. Mar. 8):
Cosmic ray data taking and analysis