JPS62201386A - Neutron detecting device - Google Patents
Neutron detecting deviceInfo
- Publication number
- JPS62201386A JPS62201386A JP61043240A JP4324086A JPS62201386A JP S62201386 A JPS62201386 A JP S62201386A JP 61043240 A JP61043240 A JP 61043240A JP 4324086 A JP4324086 A JP 4324086A JP S62201386 A JPS62201386 A JP S62201386A
- Authority
- JP
- Japan
- Prior art keywords
- neutron
- detector
- gamma ray
- gamma
- detection device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000005251 gamma ray Effects 0.000 claims abstract description 85
- 238000001514 detection method Methods 0.000 claims abstract description 51
- 239000000463 material Substances 0.000 claims abstract description 28
- 230000005855 radiation Effects 0.000 claims description 5
- 230000035945 sensitivity Effects 0.000 abstract description 9
- 239000004698 Polyethylene Substances 0.000 abstract description 4
- -1 polyethylene Polymers 0.000 abstract description 4
- 229920000573 polyethylene Polymers 0.000 abstract description 4
- 230000004992 fission Effects 0.000 abstract description 3
- 239000012188 paraffin wax Substances 0.000 abstract description 3
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 abstract description 3
- 229910052721 tungsten Inorganic materials 0.000 abstract description 3
- 239000010937 tungsten Substances 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 2
- 239000012857 radioactive material Substances 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 26
- 239000000941 radioactive substance Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 239000002901 radioactive waste Substances 0.000 description 3
- 229910052778 Plutonium Inorganic materials 0.000 description 2
- 229910052770 Uranium Inorganic materials 0.000 description 2
- OYEHPCDNVJXUIW-UHFFFAOYSA-N plutonium atom Chemical compound [Pu] OYEHPCDNVJXUIW-UHFFFAOYSA-N 0.000 description 2
- 238000012958 reprocessing Methods 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000003758 nuclear fuel Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- JFALSRSLKYAFGM-UHFFFAOYSA-N uranium(0) Chemical compound [U] JFALSRSLKYAFGM-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Monitoring And Testing Of Nuclear Reactors (AREA)
- Measurement Of Radiation (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明は放射性物質を含む被測定物から放出される中性
子を計測する中性子検出装置に係り、特にＩｌｉ用性魔
性廃棄物の固化体等の放射性物質を含む被測定物からの
中性子を非破壊で測定する中性子検出装置に関する。[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a neutron detection device that measures neutrons emitted from an object to be measured containing a radioactive substance, and particularly relates to a neutron detection device for measuring neutrons emitted from an object to be measured containing a radioactive substance. The present invention relates to a neutron detection device that non-destructively measures neutrons from an object to be measured containing a radioactive substance such as a solidified body.
（従来の技術）
原子炉用燃料の加工工場や再処理工場から廃棄される放
射性廃棄物やその同化体には、ごく微量のウラン（Ｕ）
やプルトニウム（Ｐｕ）等の核分裂性物質が含まれてい
る場合がある。これらの核分裂性物質は、自発核分裂や
周りの軽元素との（α・ｎ）反応により中性子が放出さ
れる。この中性子の放出レベルは、中性子検出装置によ
り１１１測される。(Conventional technology) Radioactive waste and its assimilated products disposed of from nuclear reactor fuel processing plants and reprocessing plants contain very small amounts of uranium (U).
It may contain fissile materials such as plutonium (Pu) or plutonium (Pu). These fissile materials emit neutrons through spontaneous nuclear fission and (α·n) reactions with surrounding light elements. This neutron emission level is measured 111 by a neutron detection device.
従来の中性子検出装置は、検出器ブロック内に放射性物
質を含む被測定物としＣの測定試料を取り囲むようにポ
リエチレン等の中性子減速材を充填し、この中性子減速
材内に熱中性子に対し感度２の良い中性子検出器を埋設
して構成され、上記中性子検出器で測定試料から放出さ
れ、中性子減速材で減速された熱中性子を検出し、中性
子レベルを甜測するようになっている。中性子検出器と
してはＨｅ−３検出器やＢＦ３検出器、Ｂ−１０検出器
等が広く用いられている。In a conventional neutron detection device, a neutron moderator such as polyethylene is filled in the detector block so as to surround a measurement sample C containing a radioactive substance, and the neutron moderator has a sensitivity of 2 for thermal neutrons. The neutron detector is constructed by embedding a neutron detector with good performance, and the neutron detector detects thermal neutrons emitted from the measurement sample and moderated by a neutron moderator, and measures the neutron level directly. As neutron detectors, He-3 detectors, BF3 detectors, B-10 detectors, etc. are widely used.
ところで、核分裂性物質を内蔵する放射性廃棄物のうら
、特に再処理工場から廃山される放射性廃棄物には中性
子の他に、γ線を放出づ′るものが多く、また放出され
るγ線のレベルも種々多様である。By the way, in addition to radioactive waste containing fissile material, especially radioactive waste discarded from reprocessing plants, there are many things that emit gamma rays in addition to neutrons; There are various levels of
他方、中性子検出装置に用いられる中性子検出器は中性
子（熱中性子）に対して感度の高い中性子検出器を使用
ザることか望ましいが、中性子検出器はその秤類にＪ：
って許容されるＴ線強瓜に限界がある。一般に、中性子
検出感度の高い中性予検１冒褐は許容されるγ線レベル
が低く、また許容γｌｉｔレベルの高い中性子検出：Ｓ
は中性子感度が低いという相反づる特徴を備えている。On the other hand, it is desirable to use a neutron detector that is highly sensitive to neutrons (thermal neutrons) for use in neutron detection equipment, but the neutron detector has J:
There is a limit to the T-line strength that is allowed. In general, neutral preliminary test 1 with high neutron detection sensitivity has a low allowable gamma ray level, and neutron detection with a high allowable gamma lit level: S
has the contradictory feature of low neutron sensitivity.
このため、通常の中性子検出装置の設計では、測定対象
の試料を予め決定し、決められた試料のγ線レベルに適
合する中性子検出器を選定するか、あるいは中性子検出
器が埋設される中性子減速材の内側に鉛等のγ線遮蔽材
を設置し、中性子検出器に入射されるγ線のレベルを調
整している。γ線遮蔽材の設問は、中性子検出効率の低
下を招くため、γ線遮蔽材の肉厚は最適化しな【ノれば
ならない。For this reason, when designing a normal neutron detection device, the sample to be measured is determined in advance, and a neutron detector that matches the gamma ray level of the sample is selected, or a neutron deceleration device in which the neutron detector is embedded is selected. A gamma ray shielding material such as lead is installed inside the material to adjust the level of gamma rays that enter the neutron detector. Regarding the question of gamma-ray shielding material, the thickness of the gamma-ray shielding material must be optimized, as this will lead to a decrease in neutron detection efficiency.
しかし、従来の中性子検出装置においては、いずれの設
５］においてら、被測定物としての試料は限定され、γ
線レベルに応じたγ線遮蔽を施ずため、レベルの低い試
料の測定では中性子検出効率の低下を招く恐れがあり、
逆に高いγ線レベルの試料の測定は不可能になる等の問
題があった。However, in any of the conventional neutron detection devices, the sample to be measured is limited, and γ
Since gamma ray shielding is not applied according to the radiation level, measurement of samples with low levels may result in a decrease in neutron detection efficiency.
On the other hand, there were problems such as making it impossible to measure samples with high gamma ray levels.
〈発明が解決しようとする問題点）
従来の中性子検出装置にＪ３いては、測定される試お１
（被測定物）は限定され、そのγ線レベルに応じたγ線
遮蔽を施１−ため、γ線レベルの低い試料の測定では、
中性子検出効率の損失を１／ｌさ、また、γ線レベルの
高い試料の測定は測定が不可能になるという問題があっ
た。(Problems to be solved by the invention) In the conventional neutron detection device, J3
(object to be measured) is limited and gamma ray shielding is applied according to its gamma ray level, so when measuring a sample with a low gamma ray level,
There were problems in that the loss of neutron detection efficiency was reduced to 1/l, and measurement of samples with high gamma ray levels became impossible.
本発明は、上述した事情を考慮してなされたもので、広
範囲に頁るγ線レベルの被測定物からの中性子を効率よ
く測定することができる中性子検出装置を提供すること
を目的とする。The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a neutron detection device that can efficiently measure neutrons from an object with a wide range of gamma ray levels.
（発明の構成）
（問題点を解決するための手段）
本作第１番［］の１発は、上述した目的を達成覆るため
に、筒状本体内に被測定物を収納する収納スペースを形
成するとともに、この収納スペースの周りに充填された
中性子減速材内に沖性子検出器を配設し、この中性子検
出器により被測定物から放出される中性子を検出する中
性子検出装置において、前記中性子減速材内には許容γ
線レベルがイれぞれ異イする複数種の中性子検出器を配
設するととｂに、前記筒状本体内にγ線検出器を備え、
上記γ線検出器で検出されるγ線レベルに応じて所定の
中性子検出器を選択したものである。(Structure of the Invention) (Means for Solving the Problems) In order to achieve the above-mentioned purpose, this work No. 1 [] has a storage space for storing the object to be measured in the cylindrical body In the neutron detection device, a neutron detector is arranged in a neutron moderator filled around the storage space, and the neutron detector detects neutrons emitted from the object to be measured. Allowable γ in moderator
When a plurality of types of neutron detectors having different radiation levels are arranged, (b) a gamma ray detector is provided in the cylindrical body,
A predetermined neutron detector is selected according to the gamma ray level detected by the gamma ray detector.
また、上述し１．：目的を達成するために、本件第２番
目の発明は、筒状本体内に被測定物を収納する収納スペ
ースを形成するととらに、この収納スペースの周りに充
１＋ｉされた中性子減速材内に中性子検出器を配設し、
この中性子検出器により被測定物から放出される中性子
を検出１゛る中性子検出装置にＪ３いて、γ線遮蔽材の
厚さが各々異なる複数の検出器ブロックを周方向に組み
合せて前記ｉｎ状木休体構成し、上記各検出器ブロック
内に中性子検出器を配設するとともに、筒状本体内にγ
線検出器を備え、このγ線検出器で検出されろγ線レベ
ルに応じて所定のγ線遮蔽材を選択したしのである。In addition, as mentioned above, 1. : In order to achieve the object, the second invention forms a storage space in which the object to be measured is stored in the cylindrical main body, and a neutron moderator filled around this storage space. A neutron detector is installed,
This neutron detector detects neutrons emitted from the object to be measured.In the neutron detection device J3, a plurality of detector blocks each having a different thickness of γ-ray shielding material are combined in the circumferential direction to detect the in-shaped tree. A neutron detector is arranged in each of the above detector blocks, and γ is arranged in the cylindrical body.
A gamma ray detector is provided, and a predetermined gamma ray shielding material is selected depending on the gamma ray level detected by the gamma ray detector.
（作用）
本イ１第１番［」の発明においては、筒状本体内に許容
γ線レベルのそれぞれ異なる複数種の中性子検出器とγ
線検出器とを備え、γ線検出：Ｓににり被測定物から放
出されるγ線レベルを七二りし、その検出出力（モニタ
出力）によりγ線レベルに応じた中性子検出器を選択し
、広範囲にＤるγ線レベルの被測定物からの中性子を効
率よく測定するものである。(Function) In the invention of No. 1 [1], a plurality of types of neutron detectors each having different allowable γ-ray levels and a γ-ray detector are provided in the cylindrical body.
Gamma ray detection: S detects the gamma ray level emitted from the object under test, and selects a neutron detector according to the gamma ray level based on its detection output (monitor output). This system efficiently measures neutrons from an object with γ-ray levels ranging over a wide range of D.
また、本件第２番目の発明に係る中性子検出装置は、γ
ｆｆＡ鴻蔽材の厚さがそれぞれ族なる検出器ブロックを
周方向に組み合せて「１状本体を構成し、各検出器ブロ
ック内に中性子検出器を配設するとともに筒状本体内に
γ線検出器を備えたもので、γ線レベルが広範囲に巨る
被測定物に対しても、γ線遮Ｉｌｆ材の厚さを選定する
ことにより、中性子検出器に入射されるγ線を調整でき
、中性子を効率よく測定することができる。Moreover, the neutron detection device according to the second invention of the present invention is
FFA Detector blocks with different thicknesses of shielding material are combined in the circumferential direction to form a single-shaped main body, and a neutron detector is disposed within each detector block, and a gamma ray detector is disposed within the cylindrical main body. By selecting the thickness of the γ-ray shielding Ilf material, the γ-rays incident on the neutron detector can be adjusted, even for objects with high γ-ray levels over a wide range. Neutrons can be measured efficiently.
（実施例）
以下、本発明に係る中性子検出装置の実施例について添
イ・１図面を参照して説明する。(Example) Hereinafter, an example of the neutron detection device according to the present invention will be described with reference to attached drawing A.1.
第１図は本発明の中性子検出装置の一実施例を承り図で
あり、図中符号１０は角筒状あるいは円筒状をなす中性
子検出装置の筒状本体としての検出器ブロックを示づ。FIG. 1 is a diagram showing an embodiment of the neutron detection device of the present invention, and reference numeral 10 in the figure indicates a detector block as a cylindrical main body of the neutron detection device having a rectangular or cylindrical shape.
この検出器ブロック１０は中火部に収納スペース１１が
形成され、この収納スペース１１内に放射性物質を含む
被測定物としての測定試料１２が出し入れ自在に収納さ
れ、この測定試料１２を取り囲む形でγｍ′ａ蔽材１３
が配置される。γ線遮蔽材１３は鉛やタングステン等で
構成され、その肉厚は中性子検出効率の低下を抑制する
ために最適ｉが選択さ゛れる。This detector block 10 has a storage space 11 formed in the medium heat section, and a measurement sample 12 as an object to be measured containing a radioactive substance is stored in this storage space 11 in a manner that can be taken in and out freely. γm′a shielding material 13
is placed. The γ-ray shielding material 13 is made of lead, tungsten, or the like, and its thickness is selected to be optimal i in order to suppress a decrease in neutron detection efficiency.
γ線遮蔽材１３の外周には測定式Ｆ１１２から放出され
る中性子を減速させる中性子減速材１５が充填される。The outer periphery of the γ-ray shielding material 13 is filled with a neutron moderator 15 that slows down the neutrons emitted from the measurement formula F112.
中性子減速材１５はポリエチレンやパラフィン、水等か
ら構成される。中性子減速材１５の内部には複数種の中
性子検出器１６とγ線検出器１７とが整列状態で埋設さ
れる。中性子検出器１６は、例えば中性子に対ツる感１
αの高いＦｌｅ−３検出器１６ａと、ｔｌ ｅ −３検
出Ｚ１６ａの中性子感度より低い中性子感度を右するｒ
３Ｆ、検出器あるいはＢ−１０検出器１６ｂど、許容γ
線レベルの高い核分裂計数管１（５ｃとの三種類が交互
に列状に配設され、各中性子検出器１６ａ、１６ｂ、１
６ｃはγ線通ｆ＆月１３の外周面から好ましくは３〜５
ｃｌＲ程度離れた位置にＪｌｉ！ 、？Ｒされる。The neutron moderator 15 is made of polyethylene, paraffin, water, or the like. A plurality of types of neutron detectors 16 and gamma ray detectors 17 are embedded in the neutron moderator 15 in an aligned manner. For example, the neutron detector 16 has a sensitivity 1 for neutrons.
Fle-3 detector 16a with high α and r with neutron sensitivity lower than neutron sensitivity of tl e -3 detection Z16a
3F, detector or B-10 detector 16b, etc., allowable γ
Three types of fission counters 1 (5c) with high radiation levels are arranged alternately in a row, and each neutron detector 16a, 16b, 1
6c is preferably 3 to 5 from the outer peripheral surface of the gamma ray passage f & month 13
Jli at a position about clR away! ,? It will be R.
そして、測定に使用される中１′／［予検出Ｚｌ ６ａ
。Then, the middle 1′/[pre-detection Zl 6a used for measurement
.
１６ｂ、１６Ｃの選択は図示しないスイッヂング回路に
より行なわれる。スイッチング回路はγ線検出器１７か
ら検出されるγ線レベルの検出信号を入力して、許容γ
線レベルに適した中性子検出器１６が選択される。Selection between 16b and 16C is performed by a switching circuit (not shown). The switching circuit inputs the detection signal of the gamma ray level detected from the gamma ray detector 17 and determines the allowable gamma ray level.
A neutron detector 16 suitable for the line level is selected.
次に、中性子検出装置の作用について説明する。Next, the operation of the neutron detection device will be explained.
中性子検出装置の検出器ブロック１０内に測定試料１２
を収納さＵて測定試料１２から放出される中性子が検出
され、中性子レベルの計測が行なわれる。（の際、測定
試料１２からＵやｐｕ等の核ｌＩ）裂付物質による中性
子とともにγ線が放出される。放出されたγ線はγ線遮
蔽材１３で遮蔽され、減表された後、γ線検出器１７で
モニタされ、γ線検出器１７設置位冒にＪ３けるγ線レ
ベルが測定される。A measurement sample 12 is placed inside the detector block 10 of the neutron detection device.
Neutrons emitted from the measurement sample 12 are detected, and the neutron level is measured. (At this time, γ-rays are emitted from the measurement sample 12 along with neutrons caused by the fissuring substance such as U and pu). The emitted gamma rays are blocked by the gamma ray shielding material 13 and subtracted, and then monitored by the gamma ray detector 17, and the gamma ray level at J3 is measured at the gamma ray detector 17 installed position.
γ線検出器１７からの出力信号（モニタ信号）１ｉ図示
しないスイッチング回路に送られる。スイッチング回路
はＴ線検出ｉ！１７からの出力信号の＾低に応じて、中
性子検出器１６の中から許容γ線レベルに適した中性子
検出器１６ａ、１６ｂまたは１６Ｇが選定され、この中
性子検出器により例えば約１０００秒程１！λの間で中
性子測定が行なわれる。An output signal (monitor signal) 1i from the γ-ray detector 17 is sent to a switching circuit (not shown). The switching circuit uses T-line detection i! Depending on the low level of the output signal from the neutron detector 17, a neutron detector 16a, 16b or 16G suitable for the permissible gamma ray level is selected from among the neutron detectors 16, and this neutron detector 1! Neutron measurements are taken between λ.
選択された中性子検出器１６は中性子減速材１５で減速
された熱中性子（低速中性子）を検出するようになって
いる。測定試わ１１２から放出される中性子はγ線遮蔽
材１３を通り中性子減速材１５に案内され、ここで減速
されて熱中性子となる。The selected neutron detector 16 is adapted to detect thermal neutrons (slow neutrons) moderated by the neutron moderator 15. Neutrons emitted from the measurement sample 112 pass through the γ-ray shielding material 13 and are guided to the neutron moderator 15, where they are moderated and become thermal neutrons.
このようにして、この中性子検出装置ｔよ、測定試料１
２のγ線レベルが広範囲に亘っても、複数種の中性子検
出器１６から許容γ線レベルに適した中性子検出器が選
択されるので、中性子を効率よく測定することができる
。In this way, this neutron detection device t, measurement sample 1
Even if the gamma ray level of No. 2 extends over a wide range, a neutron detector suitable for the allowable gamma ray level is selected from the plurality of types of neutron detectors 16, so that neutrons can be efficiently measured.
次に、中性子検出装置の他の実施例について説明する。Next, another embodiment of the neutron detection device will be described.
この実施例に示された中性子検出装置は４個の検出器ブ
ロック２０ ａ 、 ２０ ｂ 、 ２０ ｃ 、 ２
０ ｄを分割可能に組み立てて角筒状の筒状本体として
の検出器アッセンブリ２０を構成したものである。The neutron detection device shown in this embodiment has four detector blocks 20 a , 20 b , 20 c , 2
The detector assembly 20 as a rectangular cylindrical main body is constructed by assembling 0 d in a divisible manner.
複数の検出器ブロックを組み立てて円筒状の検出器アッ
センブリを構成してもＪ：い。各検出器ブロック２０ａ
〜２Ｏｄ内にはポリエチレンやパラフィン等の中性子減
速材２１が充填され、中性子減速材２１内に複数の同一
種の中性子検出器２２が埋設され、別状に配列される。It is also possible to construct a cylindrical detector assembly by assembling multiple detector blocks. Each detector block 20a
~2Od is filled with a neutron moderator 21 such as polyethylene or paraffin, and a plurality of neutron detectors 22 of the same type are embedded within the neutron moderator 21 and arranged separately.
この中性子検出器２２は中性子感度が倒れているものが
好ましい。The neutron detector 22 preferably has low neutron sensitivity.
また、各検出器ブロック２０ａ〜２０ｄの内側には１つ
の検出器ブロックを除いて鉛やタングステン等のγ線遮
蔽材２３ａ、２３ｂ、２３ｃが配置される。γ線遮蔽材
２３ａ、２３ｂ、２３ｃの厚さは各検出器ブロック２０
ａ、２０ｂ、２０ｃ毎に異なり、例えばγ線遮蔽材２３
８〜２３Ｃは時計方向廻りに次第に薄肉化されるように
、各検出；Ｓブロック２０ａ、２０ｂ、２０ｃ、２０ｄ
が配列される。Furthermore, γ-ray shielding materials 23a, 23b, and 23c made of lead, tungsten, or the like are arranged inside each of the detector blocks 20a to 20d except for one detector block. The thickness of the γ-ray shielding materials 23a, 23b, and 23c is the same as that of each detector block 20.
a, 20b, and 20c, for example, the γ-ray shielding material 23
8 to 23C are each detected in such a manner that the walls are gradually thinned clockwise;
are arranged.
そして、検出器アッセンブリ２０内に核分裂性物質を含
む被測定物としての測定試料２４が収納される一方、検
出器アッセンブリ２０の試料収納スペース２５にγ線検
出器２６が配置され、このγｔ’ｊ；ｉ検出器２６で測
定試料２４から放出されるγｆａｉ＋（を検出している
。A measurement sample 24 as an object to be measured containing fissile material is stored in the detector assembly 20, while a γ-ray detector 26 is arranged in the sample storage space 25 of the detector assembly 20, and this γt'j ;The i detector 26 detects γfai+( emitted from the measurement sample 24.
次に作用を説明する。Next, the effect will be explained.
検出器アッセンブリ２０内にγ線検出器２６を配置する
とともに、測定試料２４を収納させることにより、測定
準備が完了し、中性子計測作業が開始される。By arranging the gamma ray detector 26 and storing the measurement sample 24 in the detector assembly 20, measurement preparations are completed and neutron measurement work is started.
この中性子計測時には、測定試料２４から放出されるγ
線ｍをγ線検出器２６でモニタし、その出力信号（モニ
タ信号）の高低に応じて、図示しないスイッチング回路
により検出器ブロック２０ａ、２０ｂ、２０Ｃまたは２
Ｑ ｃｉ ｈ＜ 選定される。During this neutron measurement, γ released from the measurement sample 24
The ray m is monitored by the gamma ray detector 26, and depending on the level of the output signal (monitor signal), the detector block 20a, 20b, 20C or 2 is activated by a switching circuit (not shown).
Q ci h< selected.
この選定により、中性子計測に用いられる中性子検出器
２２が各検出器ブロック２０ａ、２０ｂ。With this selection, the neutron detectors 22 used for neutron measurement are located in each detector block 20a, 20b.
２０ｃまたは２０ｄ単位で選択される。Selected in units of 20c or 20d.
したがって、γ線検出ｆ！！ｉ２６からの出力信号の高
低に応じて検出器ブロック２０ａ、２０ｂ、２０Ｃまた
は２０ｄを切り換えることにより、γ線遮蔽材２３ａ、
２３ｂまたは２３ＣのＰｊすを選定し、γ線レベルが広
範囲に■る測定試＃１２４に対しで中性子検出器２２に
入射覆るγ線ｖＤを調整でき、中性子測量を効率よく行
なうことができる。Therefore, gamma ray detection f! ! By switching the detector blocks 20a, 20b, 20C, or 20d according to the level of the output signal from the
By selecting Pj of 23b or 23C, the γ-ray vD incident on the neutron detector 22 can be adjusted for measurement test #124 in which the γ-ray level ranges over a wide range, and neutron measurement can be carried out efficiently.
なお、第２図に示された中性子検出装置においては、各
検出器ブロック内に一種類の中性子検出器を列状に配列
した例について説明したが、各検出器ブロック内に配列
される中性子検出器を複数種使用することもできる。各
検出器ブＬ１ツク内に複数種の中性子検出器を配列した
場合には、より広範囲に回るγ線レベルをもつ測定試料
に対して、その中性子計測を効率よく行なうことができ
る。In addition, in the neutron detection device shown in FIG. 2, an example has been described in which one type of neutron detector is arranged in a row in each detector block, but the neutron detection device arranged in each detector block It is also possible to use multiple types of vessels. When a plurality of types of neutron detectors are arranged in each detector block L1, neutron measurements can be efficiently performed on a measurement sample having a gamma ray level that spreads over a wider range.
その際、γ線検出器は各検出器ブロックの中性子減速材
内に必要に応じて埋設し、中性子検出器位置にお（）る
γ線レベルを検出づ−るようにしてもよい。In this case, the gamma ray detector may be embedded in the neutron moderator of each detector block as necessary, so as to detect the gamma ray level at the neutron detector position.
以上に述べたように本発明においては、許容γ線レベル
が異なる複数種の中性子検出器を配設したり、あるいは
、γ線遮蔽材の厚さがそれぞれ異なる検出ニジ（ブロッ
クを組み合せて筒状本体を構成し、各検出器ブ【」ツク
内に中性子検出器を配設したから、γ線検出器によって
被測定物のγ線レベルをモニタし、その出力信号に応じ
て使用する中性子検出器やγ線遮蔽材の厚さを選択する
ことができるので、γ線レベルが広範囲に［■る被測定
物に対しても、その中性子を効率よく正確に検出して中
性子レベルを正確に５１測することができる。As described above, in the present invention, it is possible to arrange multiple types of neutron detectors with different allowable gamma ray levels, or to combine detection blocks (blocks) with different thicknesses of gamma ray shielding materials to form a cylindrical shape. Since the main body is configured and a neutron detector is installed in each detector block, the gamma ray level of the object to be measured is monitored by the gamma ray detector, and the neutron detector is used according to the output signal. Since the thickness of the gamma ray shielding material can be selected, the neutrons can be detected efficiently and accurately even for objects with gamma ray levels over a wide range. can do.
第１１′ＸＩは本発明に係る中性子検出装置の一実施例
を示す図、第２図は本発明の中性子検出装置の他の実施
例を示す図である。
１０・・・検出器ブロック（筒状本体）、１１・・・収
納スペース、１２．２４・・・測定試料（被測定物）、
１３．２３ａ、２３ｂ、２３ｃｍＴ線鴻蔽月、１５．２
１・・・中性子減速材、１６，１６ａ、１６ｂ、１６ｃ
、２２・・・中性子検出器、”１７．２６・・・γ線検
出器、２０・・・検出器アッセンブリ（筒状本体） 、
２０ａ、２０ｂ、２０ｃ、２０ｄ−・・検出器ブロック
。
第 ｔ 図
芋 ２ 図11'XI is a diagram showing one embodiment of the neutron detection device according to the present invention, and FIG. 2 is a diagram showing another embodiment of the neutron detection device of the present invention. 10...Detector block (cylindrical body), 11...Storage space, 12.24...Measurement sample (object to be measured),
13.23a, 23b, 23cm T-ray moon, 15.2
1... Neutron moderator, 16, 16a, 16b, 16c
, 22... Neutron detector, 17.26... Gamma ray detector, 20... Detector assembly (cylindrical body),
20a, 20b, 20c, 20d--detector block. Figure t, Figure 2
Claims (1)
成するとともに、この収納スペースの周りに充填された
中性子減速材内に中性子検出器を配設し、この中性子検
出器により被測定物から放出される中性子を検出する中
性子検出装置において、前記中性子減速材内には許容γ
線レベルがそれぞれ異なる複数種の中性子検出器を配設
するとともに、前記筒状本体内にγ線検出器を備え、上
記γ線検出器で検出されるγ線レベルに応じて所定の中
性子検出器を選択したことを特徴とする中性子検出装置
。 ２、筒状本体は角筒状あるいは円筒状検出器ブロックで
構成された特許請求の範囲第１項に記載の中性子検出装
置。 ３、中性子減速材内にはγ線検出器と複数の中性子検出
器が列状に配設される一方、許容γ線レベルの異なる複
数種の中性子検出器は交互に配列された特許請求の範囲
第１項に記載の中性子検出装置。 ４、中性子減速材の内側にはγ線遮蔽材が設置され、こ
のγ線遮蔽材により収納スペースが構成された特許請求
の範囲第１項に記載の中性子検出装置。 ５、筒状本体内に被測定物を収納する収納スペースを形
成するとともに、この収納スペースの周りに充填された
中性子減速材内に中性子検出器を配設し、この中性子検
出器により被測定物から放出される中性子を検出する中
性子検出装置において、γ線遮蔽材の厚さが各々異なる
複数の検出器ブロックを周方向に組み合せて前記筒状本
体を構成し、上記各検出器ブロック内に中性子検出器を
配設するとともに、筒状本体内にγ線検出器を備え、こ
のγ線検出器で検出されるγ線レベルに応じて所定のγ
線遮蔽材を選択したことを特徴とする中性子検出装置。 ６、複数の検出器ブロックを組み合せて角筒状あるいは
円筒状の筒状本体を構成し、上記各検出器ブロックに充
填される中性子減速材内に複数の中性子検出器が列状に
配設された特許請求の範囲第５項に記載の中性子検出装
置。 ７、組み合された各検出器ブロック間の中央部に被測定
物の収納スペースが形成され、この収納スペース内にγ
線検出器が配置された特許請求の範囲第５項に記載の中
性子検出装置。 ８、複数の検出器ブロックを組み合せて角筒状あるいは
円筒状の筒状本体を構成し、上記各検出器ブロックに充
填される中性子減速材内に許容γ線レベルの異なる複数
種の中性子検出器が列状に配列された特許請求の範囲第
５項に記載の中性子検出装置。 ９、各検出器ブロックの中性子減速材内にγ線検出器が
配設された特許請求の範囲第８項に記載の中性子検出装
置。[Claims] 1. A storage space for storing the object to be measured is formed in the cylindrical body, and a neutron detector is disposed in a neutron moderator filled around this storage space, and the neutron In a neutron detection device that detects neutrons emitted from an object to be measured using a detector, the neutron moderator contains an allowable γ
A plurality of types of neutron detectors each having a different radiation level are provided, and a gamma ray detector is provided in the cylindrical body, and a predetermined neutron detector is provided in accordance with the gamma ray level detected by the gamma ray detector. A neutron detection device characterized by selecting. 2. The neutron detection device according to claim 1, wherein the cylindrical body is constituted by a rectangular or cylindrical detector block. 3. A claim in which a gamma ray detector and a plurality of neutron detectors are arranged in a row within the neutron moderator, and the plurality of types of neutron detectors having different allowable gamma ray levels are arranged alternately. The neutron detection device according to item 1. 4. The neutron detection device according to claim 1, wherein a gamma ray shielding material is installed inside the neutron moderator, and the storage space is constituted by this gamma ray shielding material. 5. A storage space is formed in the cylindrical body to store the object to be measured, and a neutron detector is placed in the neutron moderator filled around this storage space, and the neutron detector detects the object to be measured. In a neutron detection device that detects neutrons emitted from In addition to arranging the detector, a gamma ray detector is provided in the cylindrical body, and a predetermined gamma ray is detected according to the gamma ray level detected by this gamma ray detector.
A neutron detection device characterized in that a radiation shielding material is selected. 6. A plurality of detector blocks are combined to form a rectangular or cylindrical cylindrical body, and a plurality of neutron detectors are arranged in a row within a neutron moderator filled in each of the detector blocks. A neutron detection device according to claim 5. 7. A storage space for the object to be measured is formed in the center between each combined detector block, and γ
A neutron detection device according to claim 5, in which a ray detector is arranged. 8. Multiple types of neutron detectors in which a plurality of detector blocks are combined to form a rectangular or cylindrical cylindrical body, and the neutron moderators filled in each of the detector blocks have different allowable gamma ray levels. The neutron detection device according to claim 5, wherein the neutron detectors are arranged in a row. 9. The neutron detection device according to claim 8, wherein a γ-ray detector is disposed within the neutron moderator of each detector block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61043240A JPS62201386A (en) | 1986-02-28 | 1986-02-28 | Neutron detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61043240A JPS62201386A (en) | 1986-02-28 | 1986-02-28 | Neutron detecting device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62201386A true JPS62201386A (en) | 1987-09-05 |
| JPH0523636B2 JPH0523636B2 (en) | 1993-04-05 |
Family
ID=12658376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61043240A Granted JPS62201386A (en) | 1986-02-28 | 1986-02-28 | Neutron detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62201386A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112764078A (en) * | 2020-12-22 | 2021-05-07 | 中国原子能科学研究院 | Nuclear material measuring device |
-
1986
- 1986-02-28 JP JP61043240A patent/JPS62201386A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112764078A (en) * | 2020-12-22 | 2021-05-07 | 中国原子能科学研究院 | Nuclear material measuring device |
| CN112764078B (en) * | 2020-12-22 | 2022-08-09 | 中国原子能科学研究院 | Nuclear material measuring device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0523636B2 (en) | 1993-04-05 |
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