阅读说明：本技术 伽马射线角关联测量装置及基于该装置的测量方法 (Gamma ray angle correlation measuring device and measuring method based on device ) 是由 李雪松 余功硕 师全林 代义华 白涛 张小林 解峰 姜文刚 于 2019-12-10 设计创作，主要内容包括：本发明涉及一种核数据测量装置,特别涉及一种伽马射线角关联测量装置及基于该装置的测量方法,解决了采用现有伽马射线角关联测量装置测量时,耗时耗力、对于半衰期较短的核素早期和后期测量不可兼顾以及测量精确度难以保证的问题。该装置的特殊在于：包括沿探测器布放环呈圆周分布的至少六个探测器；各探测器中轴线位于同一平面且均穿过探测器布放环圆心；探测器布放环为虚拟圆；至少六个探测器的每两个探测器中轴线的夹角中,至少一个夹角为90°；一个夹角为180°；8个夹角均大于90°小于180°,或者大于90°小于180°的夹角个数,加上将大于0°小于90°的夹角根据角关联对称原理换算后等效角大于90°小于180°的夹角个数,之和大于等于8个,且8个角互不相等。(The invention relates to a nuclear data measuring device, in particular to a gamma ray angle correlation measuring device and a measuring method based on the device, and solves the problems that when the conventional gamma ray angle correlation measuring device is used for measuring, time and labor are consumed, the measurement cannot be carried out at the early stage and the later stage of nuclide with short half-life period, and the measurement accuracy is difficult to guarantee. The device is characterized in that: the device comprises at least six detectors which are circumferentially distributed along a detector arrangement ring; the central axes of the detectors are positioned on the same plane and pass through the circle centers of the detector arranging rings; the detector arrangement ring is a virtual circle; at least one included angle in included angles of central axes of every two detectors of the at least six detectors is 90 degrees; one included angle is 180 degrees; the number of the 8 included angles is more than 90 degrees and less than 180 degrees, or more than 90 degrees and less than 180 degrees, the number of the included angles with the equivalent angle more than 90 degrees and less than 180 degrees after the included angles more than 0 degree and less than 90 degrees are converted according to the angle correlation symmetry principle is added, the sum is more than or equal to 8, and the 8 included angles are different from each other.)

1. A gamma ray angle correlation measurement apparatus, characterized by:

comprises at least six detectors;

the at least six detectors are distributed along the detector distribution ring (7) in a circumferential manner, and the central axes of the detectors are positioned on the same plane and penetrate through the circle center of the detector distribution ring (7); the detector arrangement ring (7) is a virtual circle;

at least one included angle formed by the central axes of every two detectors of the at least six detectors is 90 degrees; an included angle is 180 degrees; the number of the 8 included angles is more than 90 degrees and less than 180 degrees, or more than 90 degrees and less than 180 degrees, the number of the included angles with the equivalent angle more than 90 degrees and less than 180 degrees after the included angles more than 0 degree and less than 90 degrees are converted according to the angle correlation symmetry principle is added, the sum is more than or equal to 8, and the angle values of the 8 included angles are not equal to each other.

2. A gamma ray angle correlation measurement apparatus as claimed in claim 1, wherein: the detectors are all cylindrical gamma ray detectors.

3. A gamma ray angle correlation measurement apparatus as claimed in claim 2, wherein: the cylindrical gamma ray detector is a high-purity germanium detector or a sodium iodide detector or a lanthanum bromide detector or a cadmium zinc telluride detector.

4. A gamma ray angle correlation measurement apparatus as claimed in any one of claims 1 to 3, wherein: the number of the detectors is six.

5. A gamma ray angle correlation measurement apparatus as claimed in claim 4, wherein:

defining: the six detectors are respectively a first detector (1), a second detector (2), a third detector (3), a fourth detector (4), a fifth detector (5) and a sixth detector (6) in sequence along the anticlockwise direction; and defines:

θ₁the included angle between the central axes of the fifth detector (5) and the second detector (2) is formed;

θ₂the included angle between the central axes of the fifth detector (5) and the third detector (3) is formed;

θ₃the included angle between the central axes of the fourth detector (4) and the sixth detector (6);

θ₄the included angle between the central axes of the six-number detector (6) and the three-number detector (3) is formed;

θ₅the included angle between the central axes of the fifth detector (5) and the sixth detector (6);

θ₆the included angle between the central axis of the fifth detector (5) and the central axis of the first detector (1) is formed;

θ₇the included angle between the central axes of the first detector (1) and the third detector (3);

θ₈the included angle between the central axes of the six-number detector (6) and the second-number detector (2) is formed;

an included angle between the central axes of the first detector (1) and the second detector (2) is 90 degrees; an included angle between the central axes of the first detector (1) and the fourth detector (4) is 180 degrees; theta₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈And after the included angles larger than 0 degree and smaller than 90 degrees are converted according to the angle correlation symmetry principle, the equivalent angle is larger than 90 degrees and smaller than 180 degrees, the rest included angles are larger than 90 degrees and smaller than 180 degrees, and the angle values of 8 included angles are not equal to each other.

6. A gamma ray angle correlation measurement apparatus as claimed in claim 5, wherein:

the diameter of the detector arranging ring (7) is 500 mm;

theta is described₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈Equal to 168 °, 123 °, 115 °, 160 °, 37 °, 102 °, 135 °, 155 °, respectively.

7. A gamma ray angle correlation measurement method based on the gamma ray angle correlation measurement device according to any one of claims 1 to 6, comprising the steps of:

step 1: determining the diameter size of the detector placing ring (7);

step 2: set up gamma ray angle correlation measuring device

Step 2.1: determining the number of detectors in the gamma ray angle correlation measuring device to be built;

step 2.2: determining an included angle between the central axes of the detectors according to the number of the detectors in the gamma ray angle correlation measuring device to be built determined in the step 2.1;

step 2.3: according to the diameter size of the detector arrangement ring (7) determined in the step 1 and the included angle between the central axes of the detectors determined in the step 2.2, the construction of the gamma ray angle correlation measuring device is completed;

and step 3: placing a gamma radioactive sample to be measured (8)

Placing a gamma radioactive sample (8) to be measured at the circle center position of a detector arrangement ring (7) in the gamma ray angle correlation measuring device built in the step (2);

and 4, step 4: measuring angle related data to complete the measurement

And (3) simultaneously starting all detectors in the gamma ray angle correlation measurement device built in the step (2), measuring, obtaining angle correlation data of at least 10 different included angles, and finishing measurement.

Technical Field

The present invention relates to nuclear data measurement devices, and more particularly, to a gamma ray angle correlation measurement device and a measurement method based on the same.

Background

When the nucleus transitions from the excited state to the ground state, it sometimes completes multiple successive gamma transitions, during which multiple gamma rays are emitted. The angular association relationship of the two cascade gamma rays is directly associated with nuclear data such as nuclear energy level structure, angular momentum, transition order and the like, and is one of key parameters for measuring the nuclear data.

Referring to fig. 1, the conventional gamma ray angle correlation measurement apparatus adopts a dual-detector structure (1, ancient reynean-ann tile, a method for simultaneously measuring gamma transition angle correlation by NaI detector, university thesis of singjiang, university, 2, zhangglong, etc., angle correlation measurement of 60Ni cascade gamma transition, university physics, volume 33, ninth phase, 2014), and the structure thereof includes a fixed detector 01 and a mobile detector 02. In the measuring process, the position of the fixed detector 01 is unchanged, the movable detector 02 is rotated within the range of 90 degrees, different included angles theta are formed between the central axis of the movable detector 02 and the central axis of the fixed detector 01, and then the excited atomic nuclei are measured to obtain angle correlation data of different angles. The existing gamma ray angle correlation measuring device adopting a double-detector structure has the following defects:

(1) because a multi-position time-sharing measurement mode is adopted, at least 8 angles are required to be selected for measurement to obtain a complete angle correlation curve, namely, the measurement is carried out for at least 8 times, and the time and the labor are consumed;

(2) because each measurement needs to reach a rated statistical count, the measurement must be carried out for a long enough time, and most nuclides decay out in the later period for the nuclides with short half-lives, so that the measurement in the early period and the measurement in the later period cannot be compatible;

(3) when the displacement detector 02 is displaced, the state of the displacement detector 02 changes, and in particular the influence of electronic noise variations is disadvantageous for accurate measurements.

Although the above problem can be solved by arranging a plurality of detectors at the same time with the angle θ in the range of 90 ° to 180 °, this brings new problems: on the premise of ensuring the detection efficiency, only 4-5 detectors can be arranged due to the arrangement congestion of the detectors, 4-5 angle associated data are acquired at one time, but the angle associated curve cannot be accurately drawn by only 4-5 angle associated data.

Disclosure of Invention

The invention aims to provide a gamma ray angle correlation measuring device and a measuring method based on the device, and aims to solve the technical problems that when the conventional gamma ray angle correlation measuring device is used for measuring, time and labor are consumed, measurement cannot be carried out at the early stage and the later stage of nuclides with short half-life periods, and the measurement accuracy is difficult to guarantee.

The invention adopts the technical scheme that a gamma ray angle correlation measuring device is characterized in that:

comprises at least six detectors;

the at least six detectors are distributed along the detector distribution ring in a circumferential manner, and the central axes of the detectors are positioned on the same plane and penetrate through the circle center of the detector distribution ring; the detector arrangement ring is a virtual circle;

at least one included angle formed by the central axes of every two detectors of the at least six detectors is 90 degrees; an included angle is 180 degrees; the number of the 8 included angles is more than 90 degrees and less than 180 degrees, or more than 90 degrees and less than 180 degrees, the number of the included angles with the equivalent angle more than 90 degrees and less than 180 degrees after the included angles more than 0 degree and less than 90 degrees are converted according to the angle correlation symmetry principle is added, the sum is more than or equal to 8, and the angle values of the 8 included angles are not equal to each other.

Further, the detectors are all cylindrical gamma ray detectors.

Furthermore, the cylindrical gamma ray detector is a high-purity germanium detector or a sodium iodide detector or a lanthanum bromide detector or a cadmium zinc telluride detector.

Furthermore, in order to measure the angle correlation data required by drawing the angle correlation curve meeting the precision requirement, reduce the number of detectors as much as possible and save resources, the number of the detectors is six.

Further, defining: the six detectors are respectively a first detector, a second detector, a third detector, a fourth detector, a fifth detector and a sixth detector in turn along the anticlockwise direction; and defines:

θ₁the included angle between the central axes of the fifth detector and the second detector is formed;

θ₂the included angle between the central axes of the fifth detector and the third detector is formed;

θ₃the included angle between the central axes of the No. four detector and the No. six detector is formed;

θ₄the included angle between the central axes of the No. six detector and the No. three detector is formed;

θ₅the included angle between the central axes of the fifth detector and the sixth detector is formed;

θ₆the included angle between the central axes of the fifth detector and the first detector is formed;

θ₇the included angle between the central axes of the first detector and the third detector is formed;

θ₈the included angle between the central axes of the No. six detector and the No. two detector is formed;

an included angle between the central axes of the first detector and the second detector is 90 degrees; an included angle between the central axes of the first detector and the fourth detector is 180 degrees; theta₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈And after the included angles larger than 0 degree and smaller than 90 degrees are converted according to the angle correlation symmetry principle, the equivalent angle is larger than 90 degrees and smaller than 180 degrees, the rest included angles are larger than 90 degrees and smaller than 180 degrees, and the angle values of 8 included angles are not equal to each other.

Further, the diameter of the detector arrangement ring is 500 mm;

theta is described₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈Equal to 168 °, 123 °, 115 °, 160 °, 37 °, 102 °, 135 °, 155 °, respectively.

The invention also provides a gamma ray angle correlation measurement method based on the measurement device, which is characterized by comprising the following steps:

step 1: determining the diameter size of the detector placement ring;

step 2: set up gamma ray angle correlation measuring device

Step 2.1: determining the number of detectors in the gamma ray angle correlation measuring device to be built;

step 2.2: determining an included angle between the central axes of the detectors according to the number of the detectors in the gamma ray angle correlation measuring device to be built determined in the step 2.1;

step 2.3: according to the diameter size of the detector arrangement ring determined in the step 1 and the included angle between the central axes of the detectors determined in the step 2.2, the construction of the gamma ray angle correlation measuring device is completed;

and step 3: placing a gamma radioactive sample to be measured

Placing the gamma radioactive sample to be measured at the circle center position of a detector arrangement ring in the gamma ray angle correlation measuring device built in the step 2;

and 4, step 4: measuring angle related data to complete the measurement

And (3) simultaneously starting all detectors in the gamma ray angle correlation measurement device built in the step (2), measuring, obtaining angle correlation data of at least 10 different included angles, and finishing measurement.

The invention has the beneficial effects that:

(1) according to the gamma ray angle correlation measuring device, the gamma ray angle correlation symmetry property and the circumferential distribution space are skillfully utilized, at least six detectors are arranged on one circumference according to a certain angle, so that angle correlation data with unequal included angles of central axes of at least 10 detectors can be obtained simultaneously, and the problems that time and labor are consumed when the detectors are moved for measurement, the measurement cannot be taken into consideration for the early and later stages of nuclides with short half-life period, and the accuracy of measurement angle correlation curves is difficult to guarantee are avoided; therefore, the invention solves the technical problems that the time and the labor are consumed, the measurement of the nuclide with short half-life period in the early and the later periods cannot be considered, and the measurement accuracy is difficult to ensure when the conventional gamma ray angle correlation measurement device is used for measurement.

(2) The gamma ray angle correlation measuring device provided by the invention has the advantages that the measured angle correlation data is more than or equal to 10, and compared with the traditional method, the measurement accuracy of the angle correlation curve is obviously improved.

(3) The gamma ray angle correlation measuring device provided by the invention is provided with six detectors, namely, at least 10 angle correlation data can be obtained simultaneously, and the cost effectiveness ratio is greatly improved.

Drawings

FIG. 1 is a schematic diagram of a prior art angle correlation measurement apparatus;

the reference numerals in fig. 1 are explained as follows:

01-fixed detector, 02-mobile detector.

FIG. 2 is a schematic structural diagram of an embodiment of the present invention;

the reference numerals in fig. 2 are explained as follows:

the gamma radioactive sample measuring device comprises a detector 1, a detector 2, a detector 3, a detector three, a detector 4, a detector four, a detector 5, a detector five, a detector 6, a detector six, a detector 7, a detector arrangement ring and a gamma radioactive sample to be measured 8.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Referring to fig. 2, the invention relates to a gamma ray angle correlation measuring device, which structurally comprises at least six detectors; the at least six detectors are distributed along the detector distribution ring 7 in a circumferential manner, and the central axes of the detectors are all positioned on the same plane and all penetrate through the circle center of the detector distribution ring 7; the detector placement ring 7 is a virtual circle whose diameter size is determined by the designed detection efficiency. At least one included angle formed by the central axes of every two detectors of the at least six detectors is 90 degrees; an included angle is 180 degrees; the number of the 8 included angles is more than 90 degrees and less than 180 degrees, or more than 90 degrees and less than 180 degrees, the number of the included angles with the equivalent angle more than 90 degrees and less than 180 degrees after the included angles more than 0 degree and less than 90 degrees are converted according to the angle correlation symmetry principle is added, the sum is more than or equal to 8, and the angle values of the 8 included angles are not equal to each other. The detectors are preferably all cylindrical gamma ray detectors.

In order to measure the angular correlation data required for drawing the angular correlation curve meeting the precision requirement, reduce the number of detectors as much as possible, and save resources, the number of detectors is preferably six in the present embodiment. Referring to fig. 2, define: the six detectors are a first detector 1, a second detector 2, a third detector 3, a fourth detector 4, a fifth detector 5 and a sixth detector 6 in turn along the anticlockwise direction; and defines: theta₁The included angle between the central axes of the fifth detector 5 and the second detector 2 is formed; theta₂The included angle between the central axes of the fifth detector 5 and the third detector 3 is formed; theta₃The included angle between the central axes of the No. four detector 4 and the No. six detector 6 is formed; theta₄The included angle between the central axes of the No. six detector 6 and the No. three detector 3 is formed; theta₅The included angle between the central axes of the fifth detector 5 and the sixth detector 6 is formed; theta₆The included angle between the central axis of the detector 5 and the central axis of the detector 1 is shown as the fifth; theta₇The included angle between the central axes of the first detector 1 and the third detector 3 is formed; theta₈The included angle between the central axes of the six-number detector 6 and the second-number detector 2 is formed; an included angle between the central axes of the first detector 1 and the second detector 2 is 90 degrees; an included angle between the central axes of the first detector 1 and the fourth detector 4 is 180 degrees; theta₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈And after the included angles larger than 0 degree and smaller than 90 degrees are converted according to the angle correlation symmetry principle, the equivalent angle is larger than 90 degrees and smaller than 180 degrees, the rest included angles are larger than 90 degrees and smaller than 180 degrees, and the angle values of 8 included angles are not equal to each other. In the present embodiment, the ground is preferableThe diameter of the detector arranging ring 7 is 500 mm; theta as above₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈Equal to 168 °, 123 °, 115 °, 160 °, 37 °, 102 °, 135 °, 155 °, respectively; wherein theta is₅After conversion according to the angle correlation symmetry principle, the equivalent is 180-37 degrees to 143 degrees.

The method for performing the gamma ray angle correlation measurement on the gamma radioactive sample 8 by adopting the gamma ray angle correlation measurement device comprises the following steps:

step 1: determining the diameter size of the detector placement ring 7

Determining the diameter size of the detector layout ring 7 according to the requirement of the designed detection efficiency; the higher the requirement on the designed detection efficiency is, the smaller the diameter size of the detector layout ring 7 is;

step 2: set up gamma ray angle correlation measuring device

Step 2.1: determining the number of detectors in the gamma ray angle correlation measuring device to be built according to the precision requirement of the diagonal correlation curve; the higher the precision requirement of the general diagonal association curve is, the more the number of the detectors is;

step 2.2: determining an included angle between the central axes of the detectors according to the number of the detectors in the gamma ray angle correlation measuring device to be built determined in the step 2.1;

step 2.3: according to the diameter size of the detector arrangement ring 7 determined in the step 1 and the included angle between the central axes of the detectors determined in the step 2.2, the construction of the gamma ray angle correlation measuring device is completed;

and step 3: placing a gamma radioactive sample to be measured 8

Placing the gamma radioactive sample 8 to be measured at the circle center position of the detector arrangement ring 7 in the gamma ray angle correlation measuring device built in the step 2;

and 4, step 4: measuring angle related data to complete the measurement

And (3) simultaneously starting all detectors in the gamma ray angle correlation measurement device built in the step (2), measuring, obtaining angle correlation data of at least 10 different included angles, and finishing measurement.

In this example, gamma radioactive samples were measured⁶⁰For example, the method for measuring gamma ray angle correlation includes the following steps:

step 1: determining the diameter size of the detector placement ring 7

According to the requirement of the designed detection efficiency, in the embodiment, the diameter of the detector arrangement ring 7 is determined to be 500 mm;

step 2: set up gamma ray angle correlation measuring device

Step 2.1: according to the precision requirement of the diagonal association curve, in this embodiment, it is determined that the number of detectors in the gamma ray angle association measurement device to be built is six (in other embodiments, if the precision requirement of the diagonal association curve is improved, the number of detectors may be more than six); the high-purity germanium detector in the cylindrical gamma ray detector is selected, and besides the high-purity germanium detector, a sodium iodide detector or a lanthanum bromide detector or a cadmium zinc telluride detector can be selected;

step 2.2: determining an included angle between the central axes of the detectors according to the number of the detectors in the gamma ray angle correlation measuring device to be built determined in the step 2.1; in this embodiment, an included angle between central axes of the first detector 1 and the second detector 2 is 90 degrees; an included angle between the central axes of the first detector 1 and the fourth detector 4 is 180 degrees; theta₁、θ₂、θ₃、θ₄、θ₅、θ₆、θ₇、θ₈Equal to 168 °, 123 °, 115 °, 160 °, 37 °, 102 °, 135 °, 155 °, respectively;

step 2.3: according to the diameter size of the detector arrangement ring 7 determined in the step 1 and the included angle between the central axes of the detectors determined in the step 2.2, the construction of the gamma ray angle correlation measuring device is completed;

and step 3: placing a gamma radioactive sample to be measured 8

Gamma radioactive sample to be measured⁶⁰Placing Co at the circle center position of a detector arrangement ring 7 in the gamma ray angle correlation measuring device built in the step 2;

and 4, step 4: measuring angle related data to complete the measurement

And (3) simultaneously starting 6 detectors in the gamma ray angle correlation measurement device built in the step (2) for measurement, acquiring angle correlation data of at least 10 different included angles, and finishing the measurement.

The gamma ray angle correlation measuring device solves the problem that when the existing gamma ray angle correlation measuring device is used for measuring, the detector needs to be moved to change the angle for measuring one by one, shortens the measuring time, and can measure the angle correlation data of nuclides with short half-life period.