CAJ | 학술논문

用于硼中子俘获治疗（BNCT ）的医院中子照射器（IHNI‐Ⅰ）已由北京凯佰特技术有限公司建设完成，为获得空气中自由中子束的能谱，建立了一套改进的主动式多球谱仪，并开展了相关实验方法研究。该谱仪包含14个探测单元，中心探测器为球形3 H e正比计数器。为改善谱仪在超热能区的分辨率，在常规多球谱仪的基础上增加了4个包裹不同厚度硼壳的探测单元。通过MCNP程序计算谱仪的响应函数，并利用标准252 Cf和241 Am‐Be中子源进行了校准和验证。测量在距离照射器孔道口110 cm处进行，再采用反迭代方法将能谱修正到孔道口处，结果显示，测量的中子能谱与理论模拟结果略有差异。因而利用ROSPEC谱仪和金箔对中子能谱和PMMA体模内中子通量密度的深度曲线进行了测量，结果验证了多球谱仪测量结果的可靠性。
용우붕중자부획치료（BNCT ）적의원중자조사기（IHNI‐Ⅰ）이유북경개백특기술유한공사건설완성，위획득공기중자유중자속적능보，건립료일투개진적주동식다구보의，병개전료상관실험방법연구。해보의포함14개탐측단원，중심탐측기위구형3 H e정비계수기。위개선보의재초열능구적분변솔，재상규다구보의적기출상증가료4개포과불동후도붕각적탐측단원。통과MCNP정서계산보의적향응함수，병이용표준252 Cf화241 Am‐Be중자원진행료교준화험증。측량재거리조사기공도구110 cm처진행，재채용반질대방법장능보수정도공도구처，결과현시，측량적중자능보여이론모의결과략유차이。인이이용ROSPEC보의화금박대중자능보화PMMA체모내중자통량밀도적심도곡선진행료측량，결과험증료다구보의측량결과적가고성。
The in‐hospital neutron irradiator (IHNI‐Ⅰ) for boron neutron capture therapy (BNCT) was constructed by Beijing Capture Technology Corporation .To obtain the neutron spectra of free beams in air ,an improved active multi‐sphere spectrometer was established and the relevant experimental method was also developed .The spectrometer consisted of fourteen detection units and a spherical 3 He proportional counter was used as the central detector .In order to improve the resolution of the spectrometer in epither‐mal region ,four detection units covered with different thickness boron shells were add‐ed into the routine multi‐sphere spectrometer .The response functions of the spectrome‐ter were calculated with the MCNP code ,and calibrated and verified with standard 252 Cf and 241 Am‐Be neutron sources .The measurements were performed at 110 cm distance from exit of the irradiator ,and then the neutron spectra at the exit were deduced by an‐ti‐iteration technique .The results show that there is a little discrepancy between the measured spectra and simulated ones .Therefore ,the neutron spectra and the depth curve of neutron flux density were also measured by a ROSPEC spectrometer and gold foils .The results verified the reliability of the neutron spectra measured by the multi‐sphere spectrometer .