JP2007003347A - Instrument for measuring neutron personal dose equivalent - Google Patents

Instrument for measuring neutron personal dose equivalent Download PDF

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JP2007003347A
JP2007003347A JP2005183862A JP2005183862A JP2007003347A JP 2007003347 A JP2007003347 A JP 2007003347A JP 2005183862 A JP2005183862 A JP 2005183862A JP 2005183862 A JP2005183862 A JP 2005183862A JP 2007003347 A JP2007003347 A JP 2007003347A
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moderator
neutron
dose equivalent
neutrons
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JP4150831B2 (en
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Norio Tsujimura
憲雄 辻村
Tomoya Nunomiya
智也 布宮
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Fuji Electric Co Ltd
Japan Atomic Energy Agency
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Japan Nuclear Cycle Development Institute
Fuji Electric Systems Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To measure the personal dose equivalent with a directional dependency of dose equivalent peculiar to the human body with high sensitivity, independent to an incoming direction of neutron. <P>SOLUTION: A neutron detector 16 is installed at the center of a pellet moderator section 10 moderating neutrons, the hemisphere face of the pellet moderator section is covered by a hemisphere moderator section 14 through a thermal neutron absorber section 12, the remaining hemisphere face of the pellet moderator section is covered by a hemispherical absorber section 18 shielding/absorbing neutrons, of larger diameter than that of the aforementioned hemisphere moderator section, and an annular absorber section 20 is installed so as to encompass a part of the hemisphere moderator section and also touch the hemispherical absorber section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、飛来する中性子のエネルギーと方向に無関係に中性子個人線量当量（率）の測定を可能とした測定器に関し、更に詳しく述べると、中性子を減速する減速材部中に中性子検出器を設置し、前記減速材部を、中性子を遮へい・吸収する吸収材部の中に、その一部のみ露出するように埋設した構造の中性子個人線量当量測定器に関するものである。この技術は、原子炉施設、核燃料施設などの中性子の発生する施設及びその周辺区域における中性子測定に有用である。   The present invention relates to a measuring instrument that enables measurement of the individual dose equivalent (rate) of neutrons regardless of the energy and direction of flying neutrons. More specifically, a neutron detector is installed in a moderator that decelerates neutrons. In addition, the present invention relates to a neutron individual dose equivalent measuring instrument having a structure in which the moderator part is embedded in an absorber part that shields and absorbs neutrons so that only a part of the moderator part is exposed. This technology is useful for neutron measurements in facilities that generate neutrons, such as nuclear reactor facilities and nuclear fuel facilities, and the surrounding areas.

中性子による線量当量は、その測定の目的に応じて次の２種類に分類される。第１は、主として作業環境における放射線管理の目的で測定される「周辺線量当量」であり、例えばサーベイメータで測定する量である。第２は、作業者の個人被ばく管理において測定される「個人線量当量」であり、個人線量計で測定する量である。   The dose equivalent due to neutrons is classified into the following two types according to the purpose of the measurement. The first is an “ambient dose equivalent” measured mainly for the purpose of radiation management in the work environment, for example, an amount measured by a survey meter. The second is an “individual dose equivalent” measured in the personal exposure management of the worker, and is an amount measured by a personal dosimeter.

周辺線量当量は、その場所で人が作業したときに被ばくしうる最大線量を予想するのに使用されるため、測定器は全方位に対して等しい感度を有すること、即ち中性子の飛来する方向に依存しない測定が要求される。そこで、周辺線量当量の測定には、ポリエチレンなどの水素含有物からなる球形減速材の中心付近に、全方位に対して対称的な構造となるように（言い換えれば全方位に対して感度が等しくなるように）、単一の中性子検出器を配置した中性子測定器が広く使用されている。例えば非特許文献１には、減速材に内外２層の球形ポリエチレンを使用し、その間にＢ4 Ｃ熱中性子吸収材を配し、中心に熱中性子検出器を組み込んだ構造が「中性子レムカウンタ」として開示されている。これは、中性子による線量当量が「周辺線量当量」と「個人線量当量」とに分類分けされていなかった時代の測定器であるが、現在の考え方に照らし合わせれば、「周辺線量当量」測定器に分類される。 The ambient dose equivalent is used to predict the maximum dose that can be exposed when a person works at the site, so that the instrument has equal sensitivity in all directions, i.e. in the direction of the incoming neutrons. Independent measurements are required. Therefore, in measuring the peripheral dose equivalent, a symmetric structure with respect to all directions is formed in the vicinity of the center of the spherical moderator made of a hydrogen-containing material such as polyethylene (in other words, the sensitivity is equal to all directions). As such, neutron measuring instruments with a single neutron detector are widely used. For example, Non-Patent Document 1 discloses a structure in which a spherical polyethylene of two layers is used as a moderator, a B 4 C thermal neutron absorber is arranged between them, and a thermal neutron detector is incorporated in the center. It is disclosed as. This is a measuring instrument of the era when the dose equivalent due to neutrons was not classified into "peripheral dose equivalent" and "individual dose equivalent". are categorized.

それに対して、個人線量当量は、体表面の一箇所に取り付けた個人線量計で測定することになるため、人体そのものによる遮へい効果によって、線量当量の量そのものに方向依存性が生じる。例えば、人体の背面方向から入射する中性子については、その影響は個人線量当量には殆ど含まれないことになるからである。個人線量当量と周辺線量当量の、中性子エネルギーと入射方向に関する相違を図１に示す。中性子が正面（０°）から入射する場合においては、個人線量当量と周辺線量当量には数値的な差は殆どない。しかしながら、正面入射以外の入射角度においては、周辺線量当量が中性子の入射方向に依存しない特性を持つのに対して、個人線量当量は入射角度によって値が大きく変化する。   On the other hand, since the individual dose equivalent is measured by a personal dosimeter attached to one place on the body surface, the dose equivalent amount itself has direction dependency due to the shielding effect by the human body itself. For example, for neutrons incident from the back of the human body, the effect is hardly included in the individual dose equivalent. FIG. 1 shows the difference between the individual dose equivalent and the peripheral dose equivalent regarding the neutron energy and the incident direction. When neutrons are incident from the front (0 °), there is almost no numerical difference between the individual dose equivalent and the ambient dose equivalent. However, at an incident angle other than front incidence, the peripheral dose equivalent does not depend on the incident direction of neutrons, whereas the individual dose equivalent varies greatly depending on the incident angle.

ところが、このような個人線量当量を正確に測定できる機器は未だ開発されていない。現在使用している（実際に作業者が身につけている）個人線量計の特性は、エネルギー特性・方向特性ともに完全なものではなく、それが実際の環境下で適切に動作しているか否かは、別の基準となる測定器と比較する必要がある。また、周辺線量当量を測定することを目的に設計された中性子測定器（例えば前記のような「中性子レムカウンタ」）では、人体に特有の線量当量の方向依存性がなく、中性子による個人線量当量を過大に測定することになるため、個人線量当量を正確に測定することはできない。
「中性子レムカウンタ」鈴木敏和他、ＦＡＰＩＧ第１１７号・１９８７−１１（ＦＡＰＩＧ：The First Atomic Power Industry Group ） However, an instrument capable of accurately measuring such an individual dose equivalent has not been developed yet. The characteristics of personal dosimeters currently in use (actually worn by workers) are not perfect in terms of energy and direction characteristics, and whether they are operating properly in the actual environment. Needs to be compared with another standard measuring instrument. In addition, a neutron measuring instrument designed for measuring ambient dose equivalent (eg, the “neutron rem counter” as described above) has no direction dependency of the dose equivalent peculiar to the human body, and individual dose equivalent due to neutrons. Therefore, the individual dose equivalent cannot be measured accurately.
"Neutron Rem Counter" Toshikazu Suzuki et al., FAPIG 117 / 1987-11 (FAPIG: The First Atomic Power Industry Group)

本発明が解決しようとする課題は、人体に特有の線量当量の方向依存性を有し、中性子の飛来する方向に関係なく高い感度で個人線量当量を測定できるようにすることである。   The problem to be solved by the present invention is to have a direction dependency of a dose equivalent peculiar to the human body, and to make it possible to measure an individual dose equivalent with high sensitivity regardless of the direction in which the neutrons fly.

本発明は、中性子を減速する減速材部中に中性子検出器が設置され、前記減速材部が、その一部のみ露出するように、中性子を遮へい・吸収する吸収材部に埋設され、それによって飛来する中性子のエネルギーと方向に無関係に中性子個人線量当量の測定を可能としたことを特徴とする中性子個人線量当量測定器である。   In the present invention, a neutron detector is installed in a moderator part that decelerates neutrons, and the moderator part is embedded in an absorber part that shields and absorbs neutrons so that only a part of the moderator part is exposed, thereby This is a neutron individual dose equivalent measuring device that enables measurement of neutron individual dose equivalent regardless of the energy and direction of neutrons flying.

また本発明は、中性子を減速する小球減速材部の中心に中性子検出器が設置され、前記小球減速材部の半球面は層状の熱中性子吸収材部を介して半球減速材部で覆われ、前記小球減速材部の残りの半球面には前記半球減速材部よりも大径で中性子を遮へい・吸収する半球状吸収材部で覆われ、前記半球減速材部の一部を取り囲み且つ前記半球状吸収材部に接するように円環状吸収材部が設置されていることを特徴とする中性子個人線量当量測定器である。   Further, according to the present invention, a neutron detector is installed at the center of a small sphere moderator portion for decelerating neutrons, and the hemisphere of the small sphere moderator portion is covered with a hemisphere moderator portion via a layered thermal neutron absorber portion. The remaining hemispherical surface of the small sphere moderator portion is covered with a hemispherical absorber portion that is larger in diameter than the hemisphere moderator portion and shields and absorbs neutrons, and surrounds a part of the hemisphere moderator portion. The neutron individual dose equivalent measuring device is characterized in that an annular absorber part is installed in contact with the hemispherical absorber part.

本発明に係る個人線量当量測定器は、中性子を減速させる減速材部を、中性子を吸収する吸収材部の中に、減速材部の一部が露出するように埋設した構造としたことにより、中性子の飛来する方向に関係なく、従来の中性子周辺線量当量測定器では精度良く測定ができない中性子個人線量当量を中性子の飛来する方向に関係なく高精度で測定することが可能となる。   The personal dose equivalent measuring device according to the present invention has a structure in which the moderator part for decelerating neutrons is embedded in the absorber part for absorbing neutrons so that a part of the moderator part is exposed, Regardless of the direction in which neutrons fly, it becomes possible to measure neutron individual dose equivalents that cannot be measured with high accuracy by conventional neutron peripheral dose equivalent measuring instruments with high accuracy regardless of the direction in which neutrons fly.

本発明の中性子個人線量当量測定器では、中性子を減速する小球減速材部の中心に中性子検出器が設置されている。その小球減速材部の前方側の半球面はシート状の熱中性子吸収材部を介して半球減速材部で覆われる。前記小球減速材部の背面側の半球面は中性子を遮へい・吸収する大きな径の半球状吸収材部で覆われる。そして、前記半球減速材部の一部を取り囲み且つ前記半球状吸収材部に接するように円環状吸収材部が設置されている。なお、中性子検出器は、その検出信号を計数する計数器に接続される。   In the neutron individual dose equivalent measuring device of the present invention, a neutron detector is installed at the center of a small spherical moderator that decelerates neutrons. The hemispherical surface on the front side of the small sphere moderator part is covered with the hemisphere moderator part via the sheet-like thermal neutron absorber part. The hemispherical surface on the back side of the small spherical moderator portion is covered with a large-diameter hemispherical absorber portion that shields and absorbs neutrons. And the annular | circular shaped absorber part is installed so that a part of said hemispherical moderator part may be surrounded and the said hemispherical absorber part may be contact | connected. The neutron detector is connected to a counter that counts the detection signal.

減速材部に中性子が入射すると、中性子は減速材により減速されて熱中性子となり、減速材部の中心付近に配置された中性子検出器により検出される。計数器は検出器が検出した中性子を計数し、その計数値と換算係数から中性子線量当量を算出し表示する。一方、吸収材部に中性子が入射すると、中性子は吸収材部により吸収されるため中性子検出器には到達し難い。そのため中性子の飛来方向に対して感度が異なり、人体に特有の線量当量の方向依存性を持たせることができる。   When neutrons enter the moderator part, the neutrons are decelerated by the moderator and become thermal neutrons, which are detected by a neutron detector disposed near the center of the moderator part. The counter counts the neutrons detected by the detector and calculates and displays the neutron dose equivalent from the count value and the conversion factor. On the other hand, when neutrons enter the absorber part, the neutrons are absorbed by the absorber part, so that it is difficult to reach the neutron detector. For this reason, the sensitivity differs with respect to the direction of neutron flight, and it is possible to have the direction dependency of the dose equivalent peculiar to the human body.

図２は、本発明に係る中性子個人線量当量測定器の一実施例を示す説明図であり、Ａは正面から見た状態を、Ｂは垂直断面（ｘ−ｘ断面）をそれぞれ表している。この中性子測定器は、中性子を減速させる減速材部を、中性子を吸収する吸収材部の中に、減速材部の一部が露出するように埋設した構造である。   FIG. 2 is an explanatory view showing an embodiment of a neutron individual dose equivalent measuring device according to the present invention, in which A represents a state viewed from the front, and B represents a vertical section (xx section). This neutron measuring device has a structure in which a moderator part for decelerating neutrons is embedded in an absorber part for absorbing neutrons so that a part of the moderator part is exposed.

減速材部は、小球減速材部１０と、該小球減速材部１０の半球面を覆う熱中性子吸収材部１２と、該熱中性子吸収材部１２を覆う中径の半球減速材部１４からなる。そして前記小球減速材部１０の中心に中性子検出器１６が埋設されている。吸収材部は、前記小球減速材部１０の残りの半球面を覆う大径の半球状吸収材部１８と、前記半球減速材部１４の一部を取り囲み且つ前記大径の半球状吸収材部１８に接するように設置される円環状吸収材部２０からなる。これによって、吸収材部に、減速材部の一部が露出した状態で埋設した構造になっている。   The moderator part includes a small sphere moderator part 10, a thermal neutron absorber part 12 covering the hemisphere of the small sphere moderator part 10, and a medium-diameter hemisphere moderator part 14 covering the thermal neutron absorber part 12. Consists of. A neutron detector 16 is embedded in the center of the small ball moderator 10. The absorber part surrounds a part of the hemispherical absorber part 18 and the large-diameter hemispherical absorber part 18 that covers the remaining hemisphere of the small sphere reducer part 10 and the hemispherical absorber of the large diameter. It consists of the annular absorber part 20 installed so that the part 18 may be contact | connected. Thereby, it has a structure embedded in the absorber part with a part of the moderator part exposed.

例えば、小球減速材部１０と中径の半球減速材部１４は、比重０．９２のポリエチレンからなり、それらの外形寸法は、小球減速材部１０の直径が４．３ｃｍ、中径の半球減速材部１４の直径が１１ｃｍである。熱中性子吸収材部１２は、エネルギー特性調節のために適切な開口率を持つボロン化合物からなるシートである。大径の半球状吸収材部１８と円環状吸収材部２０は比重１．０５のボロン含有ポリエチレンからなり、それらの外形寸法は、大径の半球状吸収材部１８が直径３０ｃｍ、円環状吸収材部２０が直径３０ｃｍ×長さ８ｃｍである。   For example, the small-sphere moderator portion 10 and the medium-diameter hemispherical moderator portion 14 are made of polyethylene having a specific gravity of 0.92, and the outer dimensions of the small-sphere moderator portion 10 are 4.3 cm and the medium-diameter The diameter of the hemispherical moderator 14 is 11 cm. The thermal neutron absorber member 12 is a sheet made of a boron compound having an appropriate aperture ratio for adjusting the energy characteristics. The large-diameter hemispherical absorbent member 18 and the annular absorbent member 20 are made of boron-containing polyethylene having a specific gravity of 1.05, and the outer dimensions of the large-diameter hemispherical absorbent member 18 are 30 cm in diameter and annular absorption. The material part 20 has a diameter of 30 cm and a length of 8 cm.

中性子検出器１６としては、ここでは 3Ｈｅ比例計数管を用いている。 3Ｈｅ比例計数管では、 3Ｈｅガスは熱中性子と反応して陽子を放出し、この陽子が計数管内の 3Ｈｅガスを電離し、電気的パルス信号を生じさせる。なお、 3Ｈｅガス以外にはＢＦ3 ガスを使う場合もあり、また原理的には熱中性子を検出するシンチレーション検出器等も適用可能である。 Here, as the neutron detector 16, a 3 He proportional counter is used. In a 3 He proportional counter, 3 He gas reacts with thermal neutrons to release protons that ionize the 3 He gas in the counter and produce an electrical pulse signal. In addition, BF 3 gas may be used in addition to 3 He gas, and in principle, a scintillation detector that detects thermal neutrons is also applicable.

中性子検出器１６の出力は、計数器２２に接続され、演算回路２４を経て表示装置２６に接続される。計数器２２は、中性子検出器からの電気的パルス信号を計数する。演算回路２４は、計数を線量当量に換算する換算係数が記憶されており、線量当量への換算を行う。演算回路２４によって算出された中性子線量当量が、表示装置２６で表示される。   The output of the neutron detector 16 is connected to the counter 22 and connected to the display device 26 via the arithmetic circuit 24. The counter 22 counts the electrical pulse signal from the neutron detector. The arithmetic circuit 24 stores a conversion coefficient for converting the count into a dose equivalent, and performs conversion into a dose equivalent. The neutron dose equivalent calculated by the arithmetic circuit 24 is displayed on the display device 26.

半球減速材部１４に入射した中性子のうち高エネルギー中性子は減速材内部で減速を繰り返しつつ小球減速材部１０に到達し、熱中性子となり中性子検出器１６で検出される。半球減速材部１４に入射した中性子のうち低エネルギー中性子は、減速の過程でその一部は熱中性子吸収材部１２で吸収され、残部が小球減速材部１０に到達し、熱中性子となり中性子検出器１６で検出される。他方、吸収材部１８に入射した中性子は吸収材に含まれるポリエチレンによって減速され、さらにその殆どが吸収部に含まれるボロンによって吸収されるため、中性子検出器１６には殆ど到達しない。   Among the neutrons incident on the hemisphere moderator portion 14, high energy neutrons reach the small sphere moderator portion 10 while repeating deceleration inside the moderator and become thermal neutrons and are detected by the neutron detector 16. Among the neutrons incident on the hemispherical moderator 14, some of the low energy neutrons are absorbed by the thermal neutron absorber 12 during the deceleration process, and the remainder reaches the small sphere moderator 10 and becomes thermal neutrons. It is detected by the detector 16. On the other hand, neutrons incident on the absorber 18 are decelerated by polyethylene contained in the absorber, and most of them are absorbed by boron contained in the absorber, so that the neutron detector 16 is hardly reached.

このような構造の中性子個人線量当量測定器により得られた特性を、図３及び図４に示す。図３は検出器感度の中性子エネルギー特性を表しており、図４は検出器感度の中性子入射方向特性を表している。ここで、小球減速材部１０の前方から中性子が飛来する向きを０°としたとき、中性子個人線量当量測定器のエネルギー特性は個人線量当量の特性に近接したカーブとなり、中性子個人線量当量測定器の方向特性は個人線量当量の特性に近接したカーブとなった。   The characteristics obtained by the neutron personal dose equivalent measuring device having such a structure are shown in FIGS. FIG. 3 shows the neutron energy characteristic of the detector sensitivity, and FIG. 4 shows the neutron incident direction characteristic of the detector sensitivity. Here, when the direction in which neutrons fly from the front of the small ball moderator 10 is 0 °, the energy characteristic of the neutron personal dose equivalent measuring device becomes a curve close to the characteristic of the personal dose equivalent, and the neutron personal dose equivalent measurement The directional characteristic of the vessel was a curve close to that of individual dose equivalent.

次に、本発明に係る中性子個人線量当量測定器の使用形態について述べる。この種の中性子個人線量当量測定器は、日常的な管理に使用するための測定器（例えば、作業者が着用／使用する個人線量計やサーベイメータ、あるいは施設の壁などに取り付けるエリアモニタ）として使用するものではない。中性子のエネルギーや入射方向が不明な環境で、個人線量計が正しい（線量当量）指示値を示しているかどうかを調べるために、即ちその環境における個人線量当量の基準値を測定するために使用するものである。現在使用している中性子個人線量計（実際に作業者が身につけている）の特性は、エネルギー特性・方向特性ともに完全なものはなく、それが実際の環境下で適切に動作しているかどうかは、別の基準となる測定器と比較する必要がある。そこで、作業現場で、個人線量計と本中性子個人線量当量測定器を置き換え、そのときの両者の指示値を比較することで、個人線量計が適切な指示値を示しているかどうかを調査するのである。つまり、本発明の中性子個人線量当量測定器は、個人線量計の校正に使用することができる。   Next, the usage form of the neutron personal dose equivalent measuring device according to the present invention will be described. This type of neutron personal dose equivalent measuring instrument is used as a measuring instrument for daily management (for example, personal dosimeters and survey meters worn / used by workers, or area monitors attached to the walls of facilities) Not what you want. Used in an environment where the neutron energy and the incident direction are unknown, to check whether the personal dosimeter shows the correct (dose equivalent) reading, that is, to measure the reference value of the personal dose equivalent in that environment Is. The characteristics of the neutron personal dosimeter currently used (actually worn by the worker) are not perfect in terms of energy and direction characteristics, and whether they are operating properly in the actual environment Needs to be compared with another standard measuring instrument. Therefore, at the work site, the personal dosimeter and the neutron personal dose equivalent measuring device are replaced, and the indication values of both are compared to investigate whether the personal dosimeter shows an appropriate indication value. is there. That is, the neutron personal dose equivalent measuring device of the present invention can be used for calibration of a personal dosimeter.

個人線量当量と周辺線量当量の、中性子エネルギーと入射方向に関する相違を示すグラフ。The graph which shows the difference regarding a neutron energy and an incident direction of an individual dose equivalent and an ambient dose equivalent. 本発明に係る中性子個人線量当量測定器の一実施例を示す説明図。Explanatory drawing which shows one Example of the neutron individual dose equivalent measuring device which concerns on this invention. 中性子個人線量当量測定器感度の中性子エネルギー特性を表すグラフ。The graph showing the neutron energy characteristic of the neutron personal dose equivalent measuring instrument sensitivity. 中性子個人線量当量測定器感度の中性子入射方向特性を表すグラフ。The graph showing the neutron incident direction characteristic of the neutron personal dose equivalent measuring instrument sensitivity.

符号の説明Explanation of symbols

１０ 小球減速材部
１２ 熱中性子吸収材部
１４ 半球減速材部
１６ 中性子検出器
１８ 半球状吸収材部
２０ 円環状吸収材部
２２ 計数器
２４ 演算回路
２６ 表示装置
DESCRIPTION OF SYMBOLS 10 Small sphere moderator part 12 Thermal neutron absorber part 14 Hemisphere moderator part 16 Neutron detector 18 Hemispherical absorber part 20 Annular absorber part 22 Counter 24 Arithmetic circuit 26 Display device

Claims (2)

中性子を減速する減速材部中に中性子検出器が設置され、前記減速材部が、その一部のみ露出するように、中性子を遮へい・吸収する吸収材部に埋設され、それによって飛来する中性子のエネルギーと方向に無関係に中性子個人線量当量の測定を可能としたことを特徴とする中性子個人線量当量測定器。   A neutron detector is installed in the moderator part that decelerates neutrons, and the moderator part is embedded in the absorber part that shields and absorbs neutrons so that only a part of the moderator part is exposed, and thereby the neutron detector flying A neutron individual dose equivalent measuring device that enables measurement of neutron individual dose equivalent regardless of energy and direction. 中性子を減速する小球減速材部の中心に中性子検出器が設置され、前記小球減速材部の半球面は層状の熱中性子吸収材部を介して半球減速材部で覆われ、前記小球減速材部の残りの半球面には前記半球減速材部よりも大径で中性子を遮へい・吸収する半球状吸収材部で覆われ、前記半球減速材部の一部を取り囲み且つ前記半球状吸収材部に接するように円環状吸収材部が設置されていることを特徴とする中性子個人線量当量測定器。
A neutron detector is installed at the center of a small sphere moderator that decelerates neutrons, and the hemisphere of the small sphere moderator is covered with a hemispheric moderator through a layered thermal neutron absorber. The remaining hemisphere of the moderator part is covered with a hemispherical absorber part that shields and absorbs neutrons with a larger diameter than the hemisphere moderator part, surrounds a part of the hemisphere moderator part and absorbs the hemisphere A neutron individual dose equivalent measuring instrument, wherein an annular absorber part is installed in contact with the material part.
JP2005183862A 2005-06-23 2005-06-23 Neutron personal dose equivalent measuring instrument Expired - Fee Related JP4150831B2 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010276406A (en) * 2009-05-27 2010-12-09 Chiyoda Technol Corp Integrating-type neutron dose equivalent measuring instrument, measuring method of neutron dose equivalent, and estimation method of fast neutron incoming direction
KR20200010771A (en) * 2018-07-23 2020-01-31 한국표준과학연구원 Apparatus for measuring neutron ambient dose equivalent and the Method for measuring neutron ambient dose equivalent using thereof
CN113504559A (en) * 2021-07-05 2021-10-15 中国科学院近代物理研究所 High current pulse wide energy spectrum neutron dose rate monitoring device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010276406A (en) * 2009-05-27 2010-12-09 Chiyoda Technol Corp Integrating-type neutron dose equivalent measuring instrument, measuring method of neutron dose equivalent, and estimation method of fast neutron incoming direction
KR20200010771A (en) * 2018-07-23 2020-01-31 한국표준과학연구원 Apparatus for measuring neutron ambient dose equivalent and the Method for measuring neutron ambient dose equivalent using thereof
KR102082729B1 (en) 2018-07-23 2020-04-23 한국표준과학연구원 Apparatus for measuring neutron ambient dose equivalent and the Method for measuring neutron ambient dose equivalent using thereof
CN113504559A (en) * 2021-07-05 2021-10-15 中国科学院近代物理研究所 High current pulse wide energy spectrum neutron dose rate monitoring device

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