Cosmic-Veto HPGe Gamma-Ray Spectrometer

I. Product Description

II. Product Functions

1. Wide-Range Low-Background HPGe Detector
⚫ Relative efficiency: 50% to 170% optional;
⚫ Window options: Beryllium (Be), carbon (C), or aluminum (Al); Preamplifier is separated from the detector crystal. 2. Cosmic-Veto Detector
⚫ Large-area plastic scintillator detector, integrated with photomultiplier tubes (PMTs), covering the sides and top of the lead shield chamber. 3. Anti-Coincidence Electronics Module
⚫ Supports 7 channels of anti-coincidence inputs;
⚫ Equipped with both coincidence and anti-coincidence output interface modes;
⚫ Provides 7 channels of high-voltage (HV) outputs, adjustable from 0V to 1200V;
⚫ Provides 7 channels of low-noise low-voltage (LV) outputs, providing 12V;

⚫ Built-in baseline recovery module to ensure baseline stability under high count rates.

4. Automatic Lifting Platform for Detector Assembly

⚫ Supports the liquid nitrogen recondensing refrigerator and detector;

⚫ Equipped with automatic lifting control circuit.

5. Cooler and Refrigeration Unit

Optional LN-2 liquid nitrogen recondensing refrigerator manufactured by Beijing Zhongzhi He'an Technology Co., Ltd., with partial functions as follows:

⚫ Cooling type: Liquid nitrogen recondensing refrigeration with an electric refrigeration unit;

⚫ Indicates liquid nitrogen level and air pressure information with alarm function, equipped with RS485 or USB interface;

⚫ The liquid nitrogen can support continuous operation of the detection system for more than seven days in the absence of power;

⚫ The liquid nitrogen can support continuous operation of the detection system for more than two years under continuous power supply;

⚫ The energy resolution of the instrument remains stable during the refrigeration process;

⚫ No low-energy noise is generated during the refrigeration process.

6. Shielded Lead Chamber

⚫ Integrally cast low-background lead.

7. Multi-Channel Pulse Height Analyzer and Electronic Instruments

Taking the optional GammaSpectrum-1 digital multi-channel analyzer manufactured by Pioneer PETRO. as an example, the functions are as follows:

⚫ Crystal temperature monitoring and high-voltage protection function (high voltage is shut off based on the indication of the temperature sensor inside the detector), spectrum stabilization function, and automatic high-voltage ramping function;

⚫ Automatic pole-zero cancellation and digital gated baseline recovery function;

⚫ Pulse pile-up rejection function;

⚫ Lower Level Discriminator (LLD) function.

Pioneer PETRONUC’s GammaSharp gamma-ray spectrum analysis software (GammaSharp V2.0) is available as an option. This software integrates hardware control, spectrum acquisition,

data analysis, report generation and quality control. Guided by fully automatic analysis, it outputs results based on selectively precise interactive analysis and runs properly on all versions

of the Windows operating system.

Main functions are as follows:

Spectrometer Control: Parameter settings include fine gain adjustment, high voltage adjustment, real/live time display, upper and lower threshold setting, etc.; ⚫ Functions include parameter setting, energy calibration, efficiency calibration, nuclide identification, spectrum analysis (peak search, peak area calculation), automatic decay correction and

MDA calculation, quality control (background subtraction, efficiency-corrected weighted average activity calculation, efficiency QC charts, parent-daughter decay correction, cascade

coincidence summation correction, etc.), and automatic or manual spectrum stripping; ⚫ Efficiency Calibration: Automatically calculates efficiency calibration curves for filter samples containing dust and can directly import calculation results from passive efficiency

calibration software; ⚫ Peak Fitting: Capable of resolving overlapping peaks; ⚫ Activity Calculation: Fully automatic activity calculation function; ⚫ Fully automatic analysis and peak search functions; ⚫ Real-Time Analysis: Sidebar displays real-time fitting of selected peak positions, real-time nuclide identification and peak area calculation; ⚫ Energy Calibration: Supports manual calibration and fully automatic calibration using the nuclide library; ⚫ Nuclide Identification: Provides nuclide identification results, calculates activity, and indicates peak interference between nuclides; ⚫ Activity Calculation: For different γ peaks of the same nuclide, activity is calculated via weighted average with consideration of branching ratios and efficiency calibration factors.

Nuclides exceeding the detection limit are marked. Activity calculation generates activity results and related information for all nuclides in the library.

The optional Gammacalib V4.0 detector passive efficiency calibration software (Gammacalib for short), developed and produced by Pioneer PETRONUC, supports input of sample characteristic

parameters (including geometry, material composition and density), relative position parameters between sample and detector, as well as geometry and material parameters of surrounding

shielding materials. The software has been verified with 200 volume sources and provides the following functions:

⚫ Sample Modeling: Uses powerful CAD-based modeling to realize 3D visualized rapid modeling of volume sources of arbitrary shapes, such as cylinders (coaxial / non-coaxial),

Marinelli beakers, spheres, pipes, truncated cones, etc.;

⚫ Built-in photon cross-section database from H to Pu, including materials such as gold, aluminum, germanium, copper, brass, magnesium, carbon fiber, Mylar film, alumina, magnesia, silicon,

plastic, glass, water, calcium carbonate, air, alcohol, cellulose, cement, epoxy resin, fly ash (lignite combustion), granite, mineral oil, plexiglass, polyethylene, polyvinyl chloride, river sediment,

sand (silicon dioxide), seawater (salinity 3.5%), dry soil, wood, etc. Custom materials with arbitrary composition can be defined and manually added;