Gamma Detector:
Type: 90CC CsI(Tl) scintillator
Energy Range: 30keV – 3MeV
Sensitivity: 1400cps/μSv/h (Cs-137)
Built-in Multichannel: 512 or 1024 channels
Maximum Display Count Rate: 99999cps
Range: 10nSv/h – 100μSv/h (137Cs)
Gamma Detector (High Range):
Type: Silicon diode
Energy Range: 50keV – 6MeV
Sensitivity: 0.03cps/μSv/h (137Cs)
Range: 10nSv/h – 10Sv/h (137Cs)
Neutron Detector:
Type: LiI(Eu) scintillator
Energy Range: Thermal neutrons (0.025eV) – 15MeV
Sensitivity: 0.3cps/cm2/s (252Cf)
Range: 10nSv/h – 10Sv/h (137Cs)
Special Feature:
Automatic energy calibration using K-40 in the background, without the need of any internal radioactive source.
Identity up to 4 simultaneous isotopes.
Varying background suppression algorithm (VBS).
Data Collection:Gamma Detector:
HDSMASS software (available in Mirion’s website after interning your email address)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4790-2-1024x630.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4774-2-1024x768.jpeg)
The thick plastic cover is glued to the copper cap with silica gel, which can be removed by a screw driver. This thick layer of organic material might be used to slow down the fast neutron, since only slow neutron can be effectively detected by the scintillator.
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4775-768x1024.jpeg)
The device applies a CsI(TI)/LiI(Eu) detector produced by Scionix, type 25B3PH43/L5M-LCSTXN. This detector integrated the scintillator crystal, the photomultiplier tube, and the preamplifier.
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4776-768x1024.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4779-768x1024.jpeg)
There boards are inserted into the tube-shaped body in a ridiculous manner. Very hard to take it out without scratching other electronic parts. Be careful to ground the screw when reinstalling the board.
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4782-1-768x1024.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4784-768x1024.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4786-768x1024.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4785-768x1024.jpeg)
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_4783-768x1024.jpeg)
Originally, HDS performs pretty good, easily identifying Th232, Am241, Cs137, and so on even when they are mixed together.
![](http://www.jerrylyz.com/wp-content/uploads/2023/11/IMG_3873-768x1024.jpeg)
However, after I put it near my fusor for some time, it no longer works. The reading is extremely low, with the background being ~40cpm. The energy calibration also cannot work—often stuck at the energy calibration “Calib.NMD” and identifying wrong isotopes even when the calibration is successful. I guess this is due to the poor electromagnetic field shielding.
Moreover, the HDSMASS software cannot work properly. I have tried my Mac with M1 chip + virtual Win11, Mac with Intel chip + virtual Win10, Win7, WinXP. Either cannot correctly install the driver or cannot download the software. However, I heard people saying that the newer version, HDS101, works fine.
Due to the privacy concern, I will not put the manual and the software here. But you can download them from Mirion’s website easily.