CN107688175B - Method for fast ranging of neutron scattering camera - Google Patents
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- CN107688175B CN107688175B CN201710722263.7A CN201710722263A CN107688175B CN 107688175 B CN107688175 B CN 107688175B CN 201710722263 A CN201710722263 A CN 201710722263A CN 107688175 B CN107688175 B CN 107688175B
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Abstract
The invention provides a method for fast distance measurement of a neutron scattering camera, which is mainly applied to supervision and detection of special nuclear materials with neutron radioactivity and neutron radioactive sources and belongs to the field of special material monitoring. The method disclosed by the invention comprises the following steps: grouping and placing the liquid flash detectors, wherein the number of the front row of detectors is larger than that of the rear row of detectors, and the rear row of detectors are symmetrically placed 20-40cm away from the front row of detectors to form a group; the detection sensitive surfaces of the two groups of detectors face the target direction as much as possible, the distance between the front row of detectors and the target is as less as possible than the distance between the rear row of detectors and the target, and the mutual placement distance is basically equivalent to the distance between the targets. And comparing the difference of neutron back projection images formed by the two groups of detectors by using a neutron scattering camera consisting of the two groups of detectors to judge the distance between the target and the detectors. The method provided by the invention has the advantages of high detection speed, easy realization of algorithm, accurate ranging result, adaptation to a plurality of measuring ranges and the like.
Description
Technical Field
The invention relates to a method for quickly measuring distance by a neutron scattering camera, in particular to a method for arranging and measuring distance by a neutron scattering camera for detecting special nuclear materials, neutron sources and other radioactive substances with neutrons, and belongs to the field of special material detection.
Background
The supervision of special nuclear materials is directly related to the safety of the public and the country, high attention must be paid, and the potential nuclear material threats can be accurately positioned and quickly analyzed technically so as to cut off the circulation channels. The traditional radiation imaging technology has certain nuclear material detection capability, but cannot distinguish high-Z nuclear materials and heavy metals, and cannot make final judgment on the detected materials. In this situation, scatter imaging techniques have received much attention. Since all isotopes of nuclear material undergo spontaneous fission to emit characteristic radiation (mainly gamma and neutrons), the nuclear material can be detected and localized by detecting the radiation emitted by the nuclear material.
Neutrons are one of the characteristic factors of a particular nuclear material that can be detected. The neutron detector with special design can detect Pu by using a passive detection mode, and HEU can be found by using an active detection mode. While detecting gamma radiation for a particular nuclear material is an option for imaging, neutrons are characterized by being transparent to high-Z shielding materials, which is a preferred option in many cases.
The neutron scattering imaging technology is based on the dynamic principle that neutrons generate (n, p) scattering in a plurality of scintillation detectors to obtain incident neutron position and energy information, does not need a collimator, has a large detection imaging field of view and high detection efficiency, and can obtain neutron or gamma information in a mixed radiation field by combining a neutron and gamma discrimination method.
There are therefore a number of designs of neutron scattering cameras, such as those developed by Sandia laboratories, usa and those developed by the university of New Hampshire, neutron scattering telescope (FNIT), which can be used for the detection of special materials. However, most of the neutron scattering cameras can only detect and obtain angle back-projected images in the horizontal and vertical directions to determine the direction of the special nuclear material or the radioactive source, or detect and obtain two-dimensional projected images on a certain projection plane to determine the position of the special nuclear material or the radioactive source. Therefore, most detection cameras can only detect the direction of a special nuclear material or a radioactive source relative to the neutron scattering camera, or the three-dimensional space position of the special nuclear material or the radioactive source can be obtained by selecting a projection plane in advance. For the two detection algorithms, the most important part for obtaining the three-dimensional coordinate of the special nuclear material or the radioactive source is to obtain the distance between the special nuclear material or the radioactive source and the neutron camera, but the two algorithms cannot directly obtain the distance through one-time detection, and the specific position of the special nuclear material needs to be judged through image fusion or laser ranging.
Therefore, the invention provides a method for fast ranging of a neutron scattering camera, which is used for supervision and detection of special nuclear materials with neutron radioactivity and neutron radioactive sources.
Disclosure of Invention
The invention aims to provide a method for fast ranging of a neutron scattering camera, and particularly comprises a detector arrangement scheme and a fast ranging image comparison method. The invention is realized by the following technical scheme:
(1) the detector arrangement scheme is as follows: the detector adopted by the invention is a liquid flash detector, and the arrangement scheme of the detector for the fast ranging algorithm of the neutron scattering camera is approximately as follows:
grouping and placing the liquid flash detectors, wherein each group of detectors is divided into a front row and a rear row for placing;
the detectors in each group are completely placed in a consistent manner, the number of the detectors in the front row is larger than that of the detectors in the rear row, and the axes of all the detectors are parallel to each other;
the rear row of detectors and the front row of detectors are symmetrically arranged, namely the rear row of detectors and the front row of detectors form biaxial symmetric arrangement together;
the distance between the front row of detectors and the rear row of detectors is 20-40cm, and a group of detectors are arranged;
the detection sensitive surfaces of the two groups of detectors face the direction of the SNM or the neutron source as much as possible, and the distance between the front row of detectors and the neutron source is smaller than that between the rear row of detectors and the neutron source as much as possible;
the distances between the two groups of detectors and the position of the SNM or the neutron source are basically the same, and the mutual arrangement distance is basically equivalent to the possible distance between the SNM or the neutron source.
(2) The fast ranging image comparison method comprises the following steps: for a complete detection event, canPosition P capable of acquiring two recoil protons1、P2And deposition energy Ep1、Ep2Information, along with the time of flight (TOF) Δ t of the neutron between the two scatterings. According to the parameters, the cone (with the axis as P) where the incident neutron energy and the incident direction are located can be reconstructed1P2Half opening angle θ):
En＝Ep+En′ (1)
in the formula, EnRepresenting incident neutron kinetic energy; epRepresenting a first recoil proton deposition energy; en′Represents scattered neutron energy; theta denotes the scattering angle, and the parameters are all in the experimental system. Scattered neutron energy En′It can be calculated from the time of flight of the scattered neutrons and the distance d over which the double scatter occurs:
in the formula, constants c and mnRepresenting the speed of light and the stationary mass of neutrons, respectively.
The back projection method adopts two-dimensional plane imaging and is applied to three-dimensional imaging to reconstruct two-dimensional images with different distances. The whole detection space is divided into a series of parallel imaging planes, and for one imaging plane, the imaging plane is gridded, namely divided into small squares with the same size. Suppose a neutron is formed by Z-Z in the Z-axis directionsAt the position where the two scintillator detector units scatter, which is (x) respectively1,y1,z1) And (x)2,y2,z2). For the long cylindrical detector, the axial position is calculated by output signals of the photomultiplier tubes at two ends, the radial position cannot be measured, and the position of interaction between neutrons and the scintillator is approximately considered to be on the axis. Incident neutrons in any event z ═ zsThe position on the plane satisfies the following quadratic equation, i.e. the event cone surfaceAnd z issIntersecting conic section of planes:
[nx(x-x1)+ny(y-y1)+nz(zs-z1)]2＝λ2[(x-x1)2+(y-y1)2+(zs-z1)2] (4)
in the formula, nx,ny,nzRespectively, the components of the unit vector along the central axis direction of the event cone; λ is cos θ. For large-field detection, a faster and more effective back projection reconstruction method is established for improving the image reconstruction speed.
Along a certain selected coordinate axis direction (X axis or Y axis), coordinate values (X value or Y value) are sequentially substituted into a binary quadratic equation determined by the scattering events to be converted into a unitary quadratic equation, then whether the equation has a solution is determined according to a discriminant of the equation solution, if so, a solution meeting the equation is accurately given, and whether the equation is in the imaging region is judged. The method comprises the following specific steps:
(1) a conic form is determined from data collected for a certain scattering event.
(2) On the imaging plane, along a certain axial direction, here taking the Y axis as an example, the Y coordinate values of each small square grid are substituted into the curve equation, and the x coordinate value of the intersection point of the curve is calculated according to the calculation formula of the equation solution. If at the current y0The values are as follows:
no solution (discriminant less than zero), curve and straight line y0No intersection point is found when 0;
having a solution to x1、x2Two solutions, if x is in the coordinate range of the imaging plane, the small square where the (x, y) is located is counted once;
(3) all the panels that satisfy this scattering event are counted across all the y values. Here we assume that the probability of the source appearing in the tiles is equal for that scattering event, and the statistical probability of the tiles is equal for different scattering events;
(4) then repeating steps (1) - (3) for the next scattering event;
(5) the number of times each cell is counted over all scattering events is calculated, giving a two-dimensional distribution map of the neutron source.
In order to complete the fast distance measurement algorithm, the back projection imaging of the projection planes at different distances in the space needs to be completed first, and different from the common back projection imaging method, the method needs to utilize two groups of detectors to perform independent imaging of the projection planes at different distances in the space respectively.
By using the method, only one measurement is needed, the two groups of detectors respectively perform back projection on the same projection plane, the two projection images are compared by using a distance measurement algorithm, and a distance measurement function formula is used:
and calculating the ranging evaluation value at the distance. In the formula Gl(i, j) and Gr(i, j) are respectively the count values of projection images of the left and right detectors on the same projection plane at the ith row and jth column of pixels, wherein N isIAnd NrIs the total count of projected images. The distance measurement algorithm is used for calculating projection planes at different distances to obtain the relation between the distance measurement evaluation value and the distance, namely a distance measurement evaluation curve, and the singular point of the distance measurement function curve is observed to judge the distance of the radioactive source or the SNM.
The invention has the advantages that: the method provided by the invention comprises a detector arrangement scheme and a rapid distance measurement image comparison method, can overcome the defects of the existing detection scheme and method, and meets the monitoring requirement on the SNM or neutron radioactive source by a method for measuring the distance from a special nuclear material or radioactive source to the detector through one-time detection.
Drawings
FIG. 1 is a flow chart of a fast ranging method for a neutron scattering camera;
FIG. 2 is a schematic diagram of a neutron back projection method;
FIG. 3 is a projection image at a distance of 2m by a back projection algorithm (a) for the left detector; (b) the image of the right detector;
FIG. 4 is a projection image at a distance of 3m by a back projection algorithm (a) for the left detector; (b) the image of the right detector;
FIG. 5 shows the evaluation curve results when the distance between two sets of detectors is 4m and the distance between the radiation sources is 2 m;
FIG. 6 shows the evaluation curve results when the distance between two sets of detectors is 4m and the distance between the radiation sources is 3 m;
FIG. 7 shows the evaluation curve results when the two sets of detectors are at a distance of 8m and the source is at a distance of 3 m.
Detailed Description
The following further describes a method for fast ranging by a neutron scattering camera, with reference to the accompanying drawings, which provides three embodiments, but the present invention is not limited to the embodiments provided.
Example 1:
the detector adopts a cylindrical liquid flash detector, the distance between the front row and the rear row of each group of detectors with the height of a sensitive body being 4cm and the diameter phi of 6cm is 32.77cm, the four detectors in the rear row form a square arrangement, and the distance between the two adjacent detectors is 32.46 cm. The distance between the two groups of detectors is 4m (taking the centroid of the single liquid flash detector in the front row as a reference), the cylindrical axes of all the detectors are parallel to each other, and the sensitive detection surfaces face the neutron source or the position where the special nuclear material can be located. And placing a neutron radioactive source at the position which is 2m away from two lines of the two groups of detectors and is the same with the front row of detectors in the horizontal plane.
The range of the distance measurement is set to be 0-500 cm, and back projection imaging is performed every 1 cm. As shown in FIG. 3 and FIG. 4, the projection images of the left and right detectors at the distance of 2m and 2.5m respectively in a certain area range (horizontal direction: -100cm vertical direction: -100 cm) are shown by back projection. It can be seen that the difference between the left and right projected images at 2m is significantly smaller than at 2.5 m.
Through the ranging algorithm, the ranging evaluation curve obtained through final testing is shown in fig. 5, and it can be seen that the evaluation result value is minimum near 200cm, and the characteristic is obvious.
Example 2:
the arrangement for fast ranging of the neutron scattering camera is basically the same as that of example 1. The difference is that the neutron radioactive source is arranged at the position which is 3m away from two lines of the two groups of detectors and is at the same horizontal plane with the front row of detectors.
The range of the distance measurement is still set to be 0-500 cm, and back projection imaging is carried out every 1 cm. The distance measurement evaluation curve obtained through the final test by the distance measurement algorithm is shown in fig. 6, and it can be seen that the evaluation result value is minimum near 300cm, although the characteristic is not obvious, the result can still be determined by a maximum value searching method.
Example 3:
the arrangement for fast ranging of the neutron scattering camera is basically the same as that of example 1. The difference lies in that the distance between two groups of detectors is 8m, and a neutron radioactive source is placed at the position which is 3m away from the connecting line of the two groups of detectors and is at the same horizontal plane with the front row of detectors.
The range of the distance measurement is still set to be 0-500 cm, and back projection imaging is carried out every 1 cm. The distance measurement evaluation curve obtained through the final test by the distance measurement algorithm is shown in fig. 7, and it can be seen that the evaluation result value is minimum near 200cm, although the characteristic is not obvious, the result can still be determined by a maximum value searching method.
By way of example, the method provided by the present invention can measure the distance from a specific nuclear material or a radiation source to a detector by one-time detection.
Claims (4)
1. A method for fast ranging of a neutron scattering camera comprises an arrangement scheme and an image comparison method, and is characterized in that: the arrangement scheme is as follows: grouping and placing detectors, wherein each group of detectors is divided into two rows, the detectors in each group are completely placed in the same manner, the front and rear rows of detectors form a group of detectors, and the detection sensitive surfaces of the two groups of detectors face to the direction of the SNM or neutron source of the special nuclear material; the image comparison method is as follows: through a back projection reconstruction algorithm, the independent imaging of the projection surfaces of the two groups of detectors at different distances in the space is calculated to obtain the ranging evaluation value at the distance, and the singular point of the ranging function curve is observed to judge the radioactive source or SNThe distance of M; the back projection reconstruction algorithm is as follows: acquiring the positions P of two recoil protons in one complete detection event1、P2And deposition energy Ep1、Ep2Information and the flight time TOF delta t of the neutron between two scattering events, and the cone where the incident neutron energy and the incident direction are located can be reconstructed according to the parameters, and the axis is P1P2Half opening angle is θ:
En＝Ep+En′ (1)
in the formula, EnRepresenting incident neutron kinetic energy; epRepresenting a first recoil proton deposition energy; en′Represents scattered neutron energy; theta represents the scattering angle, and the parameters are the energy E of scattered neutrons under the experimental systemn′Calculated from the time of flight of the scattered neutrons and the distance d over which the double scatter occurs:
in the formula, constants c and mnRespectively representing the speed of light and the stationary mass of neutrons;
the back projection method adopts two-dimensional plane imaging, applies the two-dimensional plane imaging to three-dimensional imaging to reconstruct two-dimensional images with different distances, divides the whole detection space into a series of parallel imaging planes, gridds one imaging plane, divides the imaging plane into small grids with the same size, and neutrons are divided into small grids from Z to Z in the Z-axis directionsAt the position where the two scintillator detector units scatter, which is (x) respectively1，y1，z1) And (x)2，y2，z2) For the long cylindrical detector, the axial position is calculated by the output signals of the photomultiplier tubes at the two ends, the radial position cannot be measured, and the position of interaction between the neutron and the scintillator is considered to be on the axisIn any event, incident neutrons are in z ═ zsThe position on the plane satisfies the following quadratic equation, the event cone surface and z ═ zsIntersecting conic section of planes:
[nx(x-x1)+ny(y-y1)+nz(zs-z1)]2＝λ2[(x-x1)2+(y-y1)2+(zs-z1)2] (4)
in the formula, nx，ny，nzThe components of the unit vector along the central axis direction of the event cone are respectively, and lambda is cos theta;
the process of judging the distance of the radioactive source or the SNM is as follows: along a selected coordinate axis direction X axis or Y axis, sequentially substituting coordinate values X value or Y value into a binary quadratic equation determined by a scattering event to convert the coordinate values into a unitary quadratic equation, then determining whether the equation has a solution according to a discriminant of equation solution, and if so, accurately giving a solution meeting the equation and judging whether the equation is in an imaging region, wherein the steps are as follows:
(1) determining a conic curve form according to data acquired by a certain scattering event;
(2) on an imaging plane, along the Y axis, substituting the Y coordinate value of each small square grid into the curve equation, and calculating the x coordinate value of the curve intersection point according to a calculation formula of equation solution; at the current y0The values are as follows:
if the solution is not present, the discriminant is less than zero, then the curve and the straight line y0No intersection point is found when 0;
having a solution to x1、x2Two solutions, if x is in the coordinate range of the imaging plane, the small square where the (x, y) is located is counted once;
(3) traversing all the y values, and counting all the small squares meeting the scattering event, wherein the probability of the neutron source in the scattering event appearing in the small squares is equal, and the probability of the counted small squares in different scattering events is also equal;
(4) then repeating steps (1) - (3) for the next scattering event;
(5) calculating the counted times of each small square in all scattering events, and giving a two-dimensional distribution graph of the neutron source;
firstly, the back projection imaging of projection planes at different distances in a space is completed, two groups of detectors are utilized to carry out independent imaging on the projection planes at different distances in the space respectively, the two groups of detectors carry out back projection on the same projection plane respectively, a distance measurement algorithm is utilized to compare two projection images, and a distance measurement function formula is utilized:
calculating a distance measurement evaluation value at the distance, wherein Gl(i, j) and Gr(i, j) are respectively the count values of projection images of the left and right detectors on the same projection plane at the ith row and jth column of pixels, wherein N islAnd NrIs the total count of projected images; the distance measurement algorithm is used for calculating projection planes at different distances to obtain the relation between the distance measurement evaluation value and the distance, namely a distance measurement evaluation curve, and the singular point of the distance measurement function curve is observed to judge the distance of the radioactive source or the SNM.
2. The method for fast ranging of a neutron scattering camera according to claim 1, wherein: the detector be the liquid and dodge the detector, front row detector quantity is greater than back row detector quantity, and the axis of all detectors is parallel to each other.
3. The method for fast ranging of a neutron scattering camera according to claim 1, wherein: the rear-row detectors and the front-row detectors of each group of detectors are symmetrically arranged, the rear-row detectors and the front-row detectors form biaxial symmetric arrangement together, and the distance between the front-row detectors and the rear-row detectors is 20-40cm, so that a group of detectors is arranged.
4. The method for fast ranging of a neutron scattering camera according to claim 1, wherein: the detection sensitive surfaces of the two groups of detectors face to the direction of the SNM or neutron source, the distance between the front row of detectors and the neutron source is smaller than that between the rear row of detectors and the neutron source, the distances between the two groups of detectors and the position of the SNM or neutron source are the same, and the mutual placement distance is equivalent to the distance between the two groups of detectors and the position of the SNM or neutron source.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204346955U (en) * | 2014-09-26 | 2015-05-20 | 同方威视技术股份有限公司 | Utilize photoneutron transmission to the device of image objects |
| CN106415202A (en) * | 2014-06-25 | 2017-02-15 | 罗伯特·博世有限公司 | Location device and method for operating a location device |
| CN106441226A (en) * | 2016-09-08 | 2017-02-22 | 哈尔滨工程大学 | Inclination testing device based on compound interferometer structure |
| CN106664265A (en) * | 2014-07-17 | 2017-05-10 | 欧利景无线有限公司 | Wireless positioning systems |
| CN106908622A (en) * | 2017-03-15 | 2017-06-30 | 东南大学 | A kind of chromatography PIV measurement apparatus and method based on optical field imaging |
| CN107016672A (en) * | 2017-04-28 | 2017-08-04 | 上海联影医疗科技有限公司 | The method for reconstructing and device and medical image system of medical scanning image |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9952304B2 (en) * | 2015-09-10 | 2018-04-24 | Ford Global Technologies, Llc | Vehicle positioning system |
| CN107031523A (en) * | 2015-11-30 | 2017-08-11 | 法乐第未来公司 | The vehicle location based on camera is carried out using known target to determine |
-
2017
- 2017-08-22 CN CN201710722263.7A patent/CN107688175B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106415202A (en) * | 2014-06-25 | 2017-02-15 | 罗伯特·博世有限公司 | Location device and method for operating a location device |
| CN106664265A (en) * | 2014-07-17 | 2017-05-10 | 欧利景无线有限公司 | Wireless positioning systems |
| CN204346955U (en) * | 2014-09-26 | 2015-05-20 | 同方威视技术股份有限公司 | Utilize photoneutron transmission to the device of image objects |
| CN106441226A (en) * | 2016-09-08 | 2017-02-22 | 哈尔滨工程大学 | Inclination testing device based on compound interferometer structure |
| CN106908622A (en) * | 2017-03-15 | 2017-06-30 | 东南大学 | A kind of chromatography PIV measurement apparatus and method based on optical field imaging |
| CN107016672A (en) * | 2017-04-28 | 2017-08-04 | 上海联影医疗科技有限公司 | The method for reconstructing and device and medical image system of medical scanning image |
Non-Patent Citations (2)
| Title |
|---|
| 《Influence of experimental conditions on the spectroscopy investigation of 14Be by Coulomb breakup reaction》;Yu-Shou Song et.al;《Chinese Physics C》;20161231;第40卷(第5期);第1-6页 * |
| 《NE213闪烁体探测器中子探测效率模拟》;席印印 等;《原子核物理评论》;20130331;第30卷(第1期);第52-57页 * |
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