CN111458741A - Method for measuring motion direction of cosmic ray muons - Google Patents
Method for measuring motion direction of cosmic ray muons Download PDFInfo
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- CN111458741A CN111458741A CN202010195297.7A CN202010195297A CN111458741A CN 111458741 A CN111458741 A CN 111458741A CN 202010195297 A CN202010195297 A CN 202010195297A CN 111458741 A CN111458741 A CN 111458741A
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- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T5/00—Recording of movements or tracks of particles; Processing or analysis of such tracks
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- G—PHYSICS
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- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
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Abstract
The invention relates to a method for measuring the movement direction of cosmic ray muons, which is mainly applied to the fields of supervision and detection of special nuclear materials, cosmic ray, medicine, geological investigation and the like. The method mainly comprises the steps of detecting the position of the Cerenkov light emitted by the mu in the radiating body and calculating the incidence direction of the mu according to a Cerenkov light cone projection image. The incident track of the mu is obtained by utilizing Cerenkov radiation of the mu in a radiation body, detecting Cerenkov light emitted by the mu by using a position sensitive light detector, counting photon positions in a large number to obtain a light cone projection image formed by the Cerenkov radiation, and calculating the image. The invention has the advantages of high detection speed, easy realization of algorithm, accurate measurement result and the like.
Description
Technical Field
The invention belongs to the field of nuclear radiation detection, and particularly relates to a method for measuring the motion direction of cosmic ray muons.
Background
Conventional detection devices such as improved neutron and gamma ray detectors, although having high sensitivity, do not function well with small quantities of well-packaged nuclear materials; the X-ray has limited ability to penetrate through compact substances, the detection engineering is complex, the accuracy of the X-ray depends heavily on the experience and the technique of an operator, and the measurement process also brings additional radiation dose, so that the wide application of the X-ray is limited.
The muons are leptons, the flux and the energy of the muons are huge, about 10000 muons are averagely incident per minute on the sea level per square meter when reaching the ground, the average energy of the muons is 3-4 GeV, the muons are equivalent to millions of times of the energy of X rays for medical use, the muons can penetrate lead with the thickness of 2m, and the muons with higher energy can even penetrate to the depth of several km below the ground. The main research field of the cosmic ray muon imaging detection technology is the detection of nuclear materials, and the technology has great advantages in the aspect of monitoring of nuclear materials. Compared with the traditional detection imaging technology, the mu imaging detection technology has the advantages of high accuracy, low cost, high speed and no radiation hazard, and can penetrate all substances. Therefore, muons are a natural resource that is very valuable for developing applications.
The existing mu imaging detection technology mainly utilizes a multiple coulomb scattering process to detect nuclear materials, for example, a small mu imaging detection system developed in the early stage of L AN L is to place 2 position sensitive detectors above and below AN effective detection area respectively, and accurately record the incidence position and the incidence direction of mu through two orthogonal coordinates on X, Y on the detectors.
The applicant is not aware of the prior art solutions in the above field and provides a method for measuring the direction of movement of cosmic ray muons using cerenkov radiation and position sensitive photo detectors for supervision and detection of concealed nuclear materials, providing more efficient detection of small quantities of packaged and well shielded special nuclear materials.
Disclosure of Invention
The invention aims to provide a method for measuring the moving direction of cosmic ray muons, which has the advantages of high detection speed, easy algorithm realization and accurate measurement result.
The purpose of the invention is realized by the following technical scheme:
a method for cosmic ray muon motion direction measurement, comprising the steps of:
the method comprises the following steps: mu is incident into the radiating body at a certain angle to generate Cerenkov radiation and emit Cerenkov blue light;
step two: the Cerenkov blue light is incident on a sensitive surface of a position sensitive optical detector, and the light particle signals are responded and amplified through a photomultiplier;
step three: the output signal of the photomultiplier is amplified by a subsequent front-end electronic system, then the signal is collected by a signal collecting system, finally the photon position is calculated by an image generating program, and a large number of photon positions are counted to generate a Cerenkov light cone projection image;
step four: the incidence track equation of the mu is calculated by the unique corresponding light cone projection images obtained by different incidence angles of the mu, and the specific calculation method is as follows:
the surface equation of the known cone is
With a vertex of (x)0,y0,z0)；
The plane of the ellipse or the circular contour formed by the Cerenkov radiation is the xoy plane, and the equation is
Taking an appropriate 6 points on the ellipse or circle, x can be obtained0,y0,z0And the values of a, b and c to obtain the vertex coordinates P (x) of the cone0,y0,z0) From A (0, y) on an ellipse1,0)、B(0,y20) two points and a vertex P (x)0,y0,z0) The equation for the conical main line PQ, i.e., the incidence trajectory of μ can be obtained.
The invention has the beneficial effects that:
the invention has good transparency, the refractive index n is more than 1, and no flash light is generated;
the invention has high sensitivity, can obtain enough optical signals by long-time exposure to obtain a large number of photon positions, and can reconstruct an extremely weak radiation target image;
the invention has the advantages of high detection speed, easy realization of algorithm and accurate measurement result.
Drawings
FIG. 1: a flow chart of a measuring method of the incidence direction of the mu particles;
FIG. 2: schematic diagram of Cerenkov radiation generation mechanism;
FIG. 3: a device structure diagram of a Cerenkov radiation detection device;
FIG. 4: FIG. 3 is a sectional view taken along line A-A;
FIG. 5: a structural schematic diagram of a photon counting position sensitive detector based on a wedge-strip anode;
FIG. 6: schematic of a two-dimensional PCD detector.
Detailed Description
The following further describes embodiments of the present invention with reference to the accompanying drawings:
the invention aims to overcome the defects of the existing detection scheme and method, provides a method which can detect the position of Cerenkov light emitted by a mu in a radiator through a position sensitive optical detector and calculate the motion track of the mu from Cerenkov light cone projection images obtained by counting a large number of photon positions, meets the monitoring requirement on hidden nuclear materials, and can also be used in the fields of cosmic ray detection, medical images, geological exploration and the like.
To achieve the above object, the present invention provides a probe arrangement for mu movement direction measurement, comprising: the detector comprises a Cerenkov radiator and a position-sensitive optical detector, wherein a mu emits Cerenkov light in the Cerenkov radiator, and the Cerenkov light is detected by the position-sensitive optical detector; all detector sensitive surfaces are parallel to the plane of the Cerenkov radiator, the distance between the radiator and the position-sensitive light detector is determined according to the thickness of the radiator, and a complete Cerenkov light cone projection image can be obtained on the detector sensitive surfaces.
The detector adopted by the invention is a position sensitive optical detector, is used for detecting that cosmic ray muons emit Cerenkov light in a Cerenkov radiator, and a muon motion track is calculated by a Cerenkov light cone projection image, and comprises the following steps:
(1) mu is incident into the radiating body at a certain angle to generate Cerenkov radiation and emit Cerenkov blue light;
(2) cerenkov light is incident on a sensitive surface of a position sensitive light detector, and a light particle signal is responded and amplified through a photomultiplier (MPT);
(3) the output signal of MPT is amplified by the subsequent front-end electronic system, then the signal is collected by the signal collecting system, finally the photon position is calculated by the image generating program and the photon position is counted in a large quantity to generate the Cerenkov light cone projection image.
(4) The incidence track equation of the mu is calculated by the unique corresponding light cone projection images (in an ideal case, the light cone projection images are elliptical or circular) obtained by different incidence angles of the mu, and the specific calculation method is as follows:
the surface equation of the known cone is
With a vertex of (x)0,y0,z0)。
The plane of the ellipse or the circular contour formed by the Cerenkov radiation is the xoy plane, and the equation is
Taking an appropriate 6 points on the ellipse or circle, x can be obtained0,y0,z0And the values of a, b and c to obtain the vertex coordinates P (x) of the cone0,y0,z0). From A (0, y) on the ellipse1,0)、B(0,y20) two points and a vertex P (x)0,y0,z0) The equation for the conical main line PQ, i.e., the incidence trajectory of μ can be obtained.
The invention discloses a method for measuring the incidence direction of muons, which can effectively realize the marking of the arrival position of an event, generate a Cerenkov light cone projection image and calculate the incidence track of the muons.
The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.
Example 1:
as shown in fig. 1, when photons are radiated by cerenkov radiation in a radiator, a microchannel plate (MCP) responds to and amplifies an optical particle signal, a position-sensitive anode collects an MCP output signal, the MCP output signal is amplified by a subsequent front-end electronic system, a signal acquisition system acquires the signal, and finally, photon positions are calculated by an image generation program and a large number of photon positions are counted to generate an image. The incidence direction of the mu is deduced from the generated cerenkov cone projection image (ideally, an ellipse or a circle).
As shown in fig. 3, the cerenkov radiation detection device is composed of a cerenkov radiator 1, a light transmission medium 2, a reflective film 3, a light shielding layer 4, and a position sensitive detector 5. The cerenkov radiator 1 is plexiglass, the thickness of which is determined by the amount of energy incident on the mu, and is as thin as possible. The light transmission medium 2 may be air, and its length may be determined according to the thickness of the radiator. One side of a sensitive area of a microchannel plate of the position sensitive detector 5 faces the Cerenkov radiator 1 and is parallel to the Cerenkov radiator 1, except for the end face of the Cerenkov radiator 1 facing the position sensitive detector 5, the rest sides are plated with a reflecting film 3, and the reflecting film 3 is a reflecting film for generating mirror reflection. The reflective film may be made of ESR (enhanced Specular Reflector) or aluminum foil from 3M company, USA. Except the lead, the reflecting film 3 and the position sensitive detector 5 are separated from the outside by a light-shielding layer 4, and a black plastic bag can be used.
FIG. 5 is a schematic diagram of a structure of a photon counting position sensitive detector based on a wedge-strip anode, and the whole system consists of a vacuum chamber part, a front-end electronic system and an image acquisition system. The image acquisition system comprises a signal acquisition hardware platform and image generation software. The micro-channel plate converts incident photons into electrons and accelerates to excite a large number of electrons to form an electron cloud with a certain size, and the electron cloud is collected by the wedge-strip-shaped anode. After the anode collects electrons, three paths of electrode signals can be output, and the three paths of signals can be used for solving the incident position of photons through a position decoding algorithm formula of the wedge-strip anode. The position decoding algorithm is formulated as follows:
the front-end circuit system amplifies and shapes signals and keeps peak values, and therefore a signal acquisition platform can acquire the signals conveniently. The signal acquisition hardware needs to synchronously acquire three paths of electrode signals and acquire all arriving signals as far as possible. And image generation software reads data stored in the memory of the acquisition system in real time, programs are compiled according to a position decoding algorithm of the wedge-strip anode, photon positions are calculated and counted at the positions, and a complete image is obtained through counting a large number of photons.
The image formed by each Cerenkov radiation (ideally an ellipse or circle) can be calculated as the incidence direction of the mu due to the difference in the images formed at different incidence angles.
The curved surface equation of the cone is
With a vertex of (x)0,y0,z0)。
The plane of the elliptical profile formed by Cerenkov radiation is xoy plane, and the equation is
Taking an appropriate 6 points on the ellipse, x can be obtained0,y0,z0And the values of a, b and c to obtain the vertex coordinates P (x) of the cone0,y0,z0). From A (0, y) on the ellipse1,0)、B(0,y20) two points and a vertex P (x)0,y0,z0) The equation for the conical main line PQ, i.e., the incidence trajectory of μ can be obtained.
Example 2:
in the cerenkov light detecting device shown in fig. 3, the cerenkov radiator 1 is distilled water and is contained in a quartz glass container as thin as possible, and the depth thereof can be determined by the energy of incident mu. The light transmission medium 2 is air, and the length thereof may be determined according to the thickness of the radiator. The position sensitive detector 5 may be a two-dimensional silicon position sensitive detector (as shown in fig. 6), one side of a sensitive region of the position sensitive detector faces the cerenkov radiator 1 and is parallel to the cerenkov radiator, the remaining sides of the cerenkov radiator 1 except for the end face facing the position sensitive detector 5 are coated with the reflective film 3, and the reflective film 3 adopts an aluminum foil which generates mirror reflection as the reflective film. Except the lead, the reflecting film 3 and the position sensitive detector 5 are separated from the outside by a light-shielding layer 4, and black adhesive tapes can be used.
Mu produces Cerenkov radiation in distilled water, and photocurrent generated by the emitted Cerenkov light on a two-dimensional PSD detector flows through the device as two input currents and an output current. The distribution of the output current shows the position of the spot in one dimension and the distribution of the input current shows the position of the spot in the other dimension. The position algorithm formula is as follows:
and the image generation software reads the data stored in the memory of the acquisition system in real time, programs are written according to the position algorithm, photon positions are calculated and counted at the positions, and a complete Cherenkov light cone projection image is obtained through counting a large number of photons. The incidence direction of the mu can be calculated due to the difference of the images formed by different incidence angles.
A method for measuring the moving direction of cosmic ray muons in the field of nuclear radiation measurement is used for supervision and detection of special nuclear materials, and in the fields of cosmic ray, medicine, geological investigation and the like. The method is characterized in that Cerenkov radiation of muons in a radiation body is utilized, a position sensitive optical detector is used for detecting Cerenkov light emitted by the muons, the positions of a large number of photons are counted to obtain a light cone projection image formed by the Cerenkov radiation, and an incident track of the muons is obtained by applying image calculation; mu emits Cerenkov light in the Cerenkov radiator, and a position-sensitive optical detector is used for detecting the Cerenkov light; all detector sensitive surfaces are parallel to the plane of the Cerenkov radiator, the distance between the radiator and the position-sensitive optical detector is determined according to the thickness of the radiator, and a complete Cerenkov light cone projection image can be obtained on the detector sensitive surfaces; generating a Cerenkov light cone projection image by using the positions of a large number of statistical photons, wherein the elliptical shape of the light cone projection formed by different incidence angles of muons is unique, a conic curve equation is obtained through an elliptical equation, and the main axis of a cone is the incidence track of the muons.
In summary, the following steps: the invention relates to a method for measuring the motion direction of cosmic ray muons in the field of nuclear radiation measurement, which is mainly applied to the fields of supervision and detection of special nuclear materials, cosmic ray, medicine, geological exploration and the like. The method mainly comprises the steps of detecting the position of the Cerenkov light emitted by the mu in the radiating body and calculating the incidence direction of the mu according to a Cerenkov light cone projection image. The incident track of the mu is obtained by utilizing Cerenkov radiation of the mu in a radiation body, detecting Cerenkov light emitted by the mu by using a position sensitive light detector, counting photon positions in a large number to obtain a light cone projection image formed by the Cerenkov radiation, and calculating the image. The method has the advantages of high detection speed, easy algorithm realization, accurate measurement result and the like.
Claims (1)
1. A method for measuring the moving direction of cosmic ray muons is characterized by comprising the following steps:
the method comprises the following steps: mu is incident into the radiating body at a certain angle to generate Cerenkov radiation and emit Cerenkov blue light;
step two: the Cerenkov blue light is incident on a sensitive surface of a position sensitive optical detector, and the light particle signals are responded and amplified through a photomultiplier;
step three: the output signal of the photomultiplier is amplified by a subsequent front-end electronic system, then the signal is collected by a signal collecting system, finally the photon position is calculated by an image generating program, and a large number of photon positions are counted to generate a Cerenkov light cone projection image;
step four: the incidence track equation of the mu is calculated by the unique corresponding light cone projection images obtained by different incidence angles of the mu, and the specific calculation method is as follows:
the surface equation of the known cone is
With a vertex of (x)0,y0,z0)；
The plane of the ellipse or the circular contour formed by the Cerenkov radiation is the xoy plane, and the equation is
Taking an appropriate 6 points on the ellipse or circle, x can be obtained0,y0,z0And the values of a, b and c to obtain the vertex coordinates P (x) of the cone0,y0,z0) From A (0, y) on an ellipse1,0)、B(0,y2,0)Two points and a vertex P (x)0,y0,z0) The equation for the conical main line PQ, i.e., the incidence trajectory of μ can be obtained.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004294106A (en) * | 2003-03-25 | 2004-10-21 | Mitsui Eng & Shipbuild Co Ltd | Apparatus for detecting two-dimensional position of incidence light |
| CN1742241A (en) * | 2002-12-09 | 2006-03-01 | 搭篷技术公司 | A system and method of adaptive control of processes with varying dynamics |
| US20090218495A1 (en) * | 2006-05-15 | 2009-09-03 | Eldim Sa | Device and Method for Discriminating Cernkov and Scintillation Radiation |
| JP2011180069A (en) * | 2010-03-03 | 2011-09-15 | Sed Kk | Device for observation of physical phenomenon |
| CN102981180A (en) * | 2012-12-12 | 2013-03-20 | 中国科学院国家天文台 | Water Cerenkov light high-energy particle detector |
| CN103018763A (en) * | 2012-12-12 | 2013-04-03 | 中国科学院国家天文台 | Detection device and method of gamma rays and cosmic rays |
| CN108107464A (en) * | 2017-12-06 | 2018-06-01 | 哈尔滨工程大学 | A kind of cluster type plastic optical fiber lantern |
| CN108885275A (en) * | 2016-04-06 | 2018-11-23 | 浜松光子学株式会社 | Radioactive rays position detector and PET device |
| US20180356554A1 (en) * | 2015-11-23 | 2018-12-13 | Istituto Nazionale Di Astrofisica | Apparatus and method for non-invasive inspection of solid bodies by muon imaging |
| US20190243010A1 (en) * | 2016-10-27 | 2019-08-08 | Hamamatsu Photonics K.K. | Charged particle track detector |
-
2020
- 2020-03-19 CN CN202010195297.7A patent/CN111458741A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1742241A (en) * | 2002-12-09 | 2006-03-01 | 搭篷技术公司 | A system and method of adaptive control of processes with varying dynamics |
| JP2004294106A (en) * | 2003-03-25 | 2004-10-21 | Mitsui Eng & Shipbuild Co Ltd | Apparatus for detecting two-dimensional position of incidence light |
| US20090218495A1 (en) * | 2006-05-15 | 2009-09-03 | Eldim Sa | Device and Method for Discriminating Cernkov and Scintillation Radiation |
| JP2011180069A (en) * | 2010-03-03 | 2011-09-15 | Sed Kk | Device for observation of physical phenomenon |
| CN102981180A (en) * | 2012-12-12 | 2013-03-20 | 中国科学院国家天文台 | Water Cerenkov light high-energy particle detector |
| CN103018763A (en) * | 2012-12-12 | 2013-04-03 | 中国科学院国家天文台 | Detection device and method of gamma rays and cosmic rays |
| US20180356554A1 (en) * | 2015-11-23 | 2018-12-13 | Istituto Nazionale Di Astrofisica | Apparatus and method for non-invasive inspection of solid bodies by muon imaging |
| CN108885275A (en) * | 2016-04-06 | 2018-11-23 | 浜松光子学株式会社 | Radioactive rays position detector and PET device |
| US20190243010A1 (en) * | 2016-10-27 | 2019-08-08 | Hamamatsu Photonics K.K. | Charged particle track detector |
| CN108107464A (en) * | 2017-12-06 | 2018-06-01 | 哈尔滨工程大学 | A kind of cluster type plastic optical fiber lantern |
Non-Patent Citations (2)
| Title |
|---|
| 宋玉收: "与K～+介子相关的超核_Λ～（209）Pb的裂变研究", 《中国优秀博硕士学位论文全文数据库（博士） 基础科学辑》 * |
| 罗鑫: "宇生μ子探测器蒙特卡罗模拟环境的初步搭建", 《大学物理》 * |
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