用于测量放射性和电离辐射能量（如 α 粒子） 的移动低成本光谱仪_Python_JavaScript_代码_相关文件_下载

<img align="right" src="https://github.com/ozel/DIY_particle_detector/raw/master/images/Alpha-spectrometer_with_ceramics_in_chocolate_box.jpeg" width="400"> *Corresponding scientific article:* [](https://doi.org/10.3390/s19194264) *Repository archive on Zenodo:* [](https://doi.org/10.5281/zenodo.3361755) # DIY Particle Detector **Short summary video on twitter**<br> :point_right: https://twitter.com/CERN/status/1260600298206302210 A mobile low-cost spectrometer for measuring ionising radiation like alpha particles and electrons (energy range: 33 keV to 8 MeV). It's an experimental educational tool and citizen science device made for exploring natural and synthetic sources of radioactivity such as stones, airborne radon, potassium-rich salt or food and every-day objects (Uranium glass, ceramics, old Radium watches etc.). <u>*The main project documentation can be found in **[the Wiki](https://github.com/ozel/DIY_particle_detector/wiki)**.*</u> A summary of the main aspects can be found below. The hardware design and documentation is licenced under the [CERN Open Hardware License](https://github.com/ozel/DIY_particle_detector/blob/master/hardware/V1.2/CERN_OPEN_HARDWARE_LICENSE_OHL_v_1_2.txt). The open source software is provided under the terms of the [BSD licence](https://github.com/ozel/DIY_particle_detector/blob/master/LICENSE). This project received funding and support by [CERN](http://home.cern) and the [Fellow FreiesWissen program](https://github.com/ozel/DIY_particle_detector/wiki/Fellow-FreiesWissen-Project). <img src="https://upload.wikimedia.org/wikipedia/en/a/ae/CERN_logo.svg" height="51"> &#8195; <img src="https://www.wikimedia.de/wp-content/uploads/2019/09/kachellogo-fellow-Programm.png" height="51"> ***Project Overview:*** * [How does it work?](#how-does-it-work) * [Hardware](#hardware) * [Two variants](#detector-variants): Electron-Detector (easier, lower costs) and Alpha-Spectrometer (more advanced) * [General requirements](#general-requirements) * [Detector signals](#detector-signals) * [Software](#software) for recording and analysing measurements * [Reference measurements and plots](#reference-measurements-and-plots) * [Workshops](#workshops) with high-school students, teachers and makers *Much more detailed information is available in **[the project Wiki](https://github.com/ozel/DIY_particle_detector/wiki)**.* ## How does it work? Tiny amounts of electrical charge are generated in repurposed photodiodes by impinging particles. The charges form currents which are amplified and converted into voltage pulses that are compatible with audio/microphone signal inputs. The size of the pulse is proportional to the energy deposited by the ionising radiation. A reference calibration with sources of known energy spectra is provided. <br><br><img align="right" src="https://github.com/ozel/DIY_particle_detector/raw/master/images/pulse_rain.png" width="300"> A superposition of several recorded pulse waveforms from electrons of beta decays (KCl salt sample, more info below) is shown on the right. This is the raw analog ouput signal of the detector. Black lines in the upper area represent electronic noise, detected signal pulses from the natural radioactivity of potassium (isotope K-40) are highlighted in red. <br> <br> <br> <img align="right" src="https://github.com/ozel/DIY_particle_detector/raw/master/images/Alpha_spectrum_Majolika_ceramic.png" width="300"> The energy spectrum on the right - derived from the size of signal pulses - was taken from an old ceramics pendant of the Majolika manufacture (Karlsruhe/Germany) - without vacuum pump, in normal ambient air! The characteristic alpha energies of the uranium isotopes are about 1 MeV lower than the actual values due to internal absorption caused by the transparent surface coating on top of the orange uranium-based glaze. More details on the energy calibration below and in the [paper](https://doi.org/10.3390/s19194264). <br> <br> ## Hardware <img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.1/documentation/DIY_Particle_Detector_in_candy-tin-box.jpg" height="350"><img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.1/documentation/DIY_Particle_Detector_in_cast-aluminium-case.jpg" height="350"> <img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/Alpha_spectrometer_in_candy_box_open.jpg" height="313"><img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/Alpha_spectrometer_in_candy_box_closed.jpg" height="313"> More photos of finished builds from users around the world can be found in the [picture gallery](https://github.com/ozel/DIY_particle_detector/wiki/Gallery). The open hardware design in this repository is released under the terms of the CERN Open Hardware Licence V1.2. Usage guidelines and legal requirements for users of this license can be found [here](https://ohwr.org/project/cernohl/wikis/Documents/CERN-OHL-version-1.2). ### Detector Variants The same circuit board is used with two partially different sets of components in two assembly variants. For electronic beginners, starting with the electron-detector version is *highly recommended* over the alpha-spectrometer. * ***Alpha-spectrometer*** measuring energies of alpha particles and electrons using one BPX61 diode.<br/> <img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/3D_top_alpha.png" height="200"><img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/3D_bottom_alpha.png" height="200"><br/> After the glass window of the diode is carefully broken-up and removed, it can sense alpha particles (see close-up pictures in the [wiki](https://github.com/ozel/DIY_particle_detector/wiki/Diodes#preparation-of-the-bpx61-diode-for-alpha-spectroscopy). The circuit works most precise with only one BPX61 diode (lowest electronic noise) and was specificaly tuned for this scenario. * [get alpha-spectrometer parts & circuit board via kitspace](https://kitspace.org/boards/github.com/ozel/diy_particle_detector/diy%20alpha%20spectrometer/) * [short parts overview & assembly guide for the alpha-spectrometer](https://raw.githubusercontent.com/ozel/DIY_particle_detector/master/hardware/V1.2/documentation/DIY%20detector%20-%20parts%20overview%20v1-2%20alphaspectrometer%20version.pdf) * [detailed assembly instructions and list of required tools](https://github.com/ozel/DIY_particle_detector/wiki/Assembly-Instructions) * [scientific article incl. reference energy calibration with alpha sources](https://doi.org/10.3390/s19194264) * ***Electron/beta radiation detector*** measuring mostly electrons (plus few gamma photons) with four very low-cost BPW34F or BPW34FA diodes (<1 EUR each).<br/> <img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/3D_top_electron.png" height="200"><img src="https://github.com/ozel/DIY_particle_detector/raw/master/hardware/V1.2/documentation/3D_bottom_electron.png" height="200"><br/> This variant is not able to detect alpha particles but is easier to operate (less sensitive to visible light and electromagnetic interference, see section on general requirements below). It is also more sensitive towards sources of low intensity (low rate of radioactive decays) since it has four times the sensor volume compared to using only one diode as sensor. This version is ideal for beginners, in total only 8 components are different compared to the alpha-spectrometer variant above. This variant is similar to the previous circuit version 1.1. * [get electron-detector parts & circuit board via kitspace](https://kit