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Inverse Calculation and Regularization Process for the Solar Aspect System(SAS) of HXI Payload on ASO-S Spacecraft

Research in Astronomy and Astrophysics 2024年第4期24卷 13-34页

作者： Ji-Rui Yu Ping Ruan Yang Su Ying-Hong He Jin-You Tao Zhe Zhang Song Guo Bin Xue Jian-Feng Yang Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences Xi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 20034China School ofAstronomy and Space Science Universityof Science and Technology of ChinaHefei 230026China

For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.

关键词： methods:data analysis Sun:flares Sun:X-rays gamma rays

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A comparison of ionizing radiation damage in CMOS devices from ^(60)Co gamma rays,electrons and protons

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Chinese Physics C 2009年第6期33卷 436-439页

作者：何宝平姚志斌张凤祁 Northwest Institute of Nuclear Technology

Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using ^60Co gamma rays, 1 MeV electrons and 1-9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts （△Vth） generated by ^60Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts （△Vth） generated by ^60Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons energy the proton has, the less serious below 9 MeV is always less than the radiation damage becomes. that of ^60Co gamma rays. The lower

关键词： gamma rays electrons protons radiation damage

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Optimization and control of synchrotron emission in ultraintense laser–solid interactions using machine learning – CORRIGENDUM

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High Power Laser Science and Engineering 2024年第1期12卷 116-116页

作者： J.Goodman M.King E.J.Dolier R.Wilson R.J.Gray P.McKenna 不详

Due to an isolated error in the 3D simulation parameters,the laser energy and intensity(calculated using the energy)values were incorrectly stated as 10.9 J and 3×10^(22) W cm^(−2),respectively,in Sections 3.3,7 and 8.The correct values are 39.8 J and 1.1×10^(23) W cm^(−2).Similarly,the values stated for the higher energy case,109 J and 3×10^(23) W cm^(−2) in Section 7,should be 398 J and 1.1×10^(24) W cm^(−2),respectively.

关键词： Bayesian optimization gamma rays laser-solid interactions machine learning radiation reaction

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Attenuation coefficients of gamma and X-rays passing through six materials

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Nuclear Science and Techniques 2020年第1期31卷 26-31页

作者： Xue-Dou Su Gao-Long Zhang Shou-Ping Xu Wei-Wei Qu Lin Song Yu-Hua Huang Ben Wang Yi-Feng Wang Ze-Tao Zhang Wu-Fu Xu Ming-Li Wang School of Physics and Nuclear Energy Engineering Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Beihang UniversityBeijing 100083China Department of Radiation Oncology PLA General HospitalBeijing 100853China State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China

The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chosen to measure gamma and X-ray attenuation coefficients and to explore the mechanisms of interaction of gamma and X-rays with matter of various kinds.It is shown that the attenuation coefficients first decrease and then increase with increase in the radiation(photon)energy.The attenuation of gamma and X-rays passing through materials with high atomic number is greater than that in materials with low atomic number.The attenuation minimum is related to the atomic number of the irradiated materials.The larger the atomic number is,the lower the energy corresponding to attenuation minimum is.Photoelectric and Compton effects are the main processes when gamma rays pass through individual materials with high and low atomic numbers,respectively.Therefore,for radiotherapy and radiation protection,different methods should be considered and selected for the use of gamma and X-rays of different energies for use in different materials.

关键词： Attenuation coefficient Interaction mechanisms gamma rays High-energy X-rays Therapy and protection

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Effectiveness of ultrafine bubbles and gamma irradiation treatments to improve seed viability and vigor of Albizia chinensis(Osbeck)Merr.

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Journal of Forestry Research 2022年第5期33卷 1607-1613页

作者： Dede J.Sudrajat Anindyta Putri Y.Aris Purwanto Iskandar Z.Siregar Forest Tree Seed Technology Research and Development Center Jl.Pakuan CiheuleutPO BOX 105BogorWest JavaIndonesia Department of Silviculture Faculty of Forestry and EnvironmentIPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia Department of Mechanical and Biosystem Engineering IPB UniversityJl.Lingkar Kampus DramagaBogor 16680West JavaIndonesia

Ultrafine bubbles and low doses of gamma irradiation had a positive effect on seed germination.This research tested the effectiveness of ultrafine bubbles(UFB)water and gamma irradiation for improving the viability and vigor of Albizia chinensis(Osbeck)Merr.seeds that had been stored for four years.A completely randomized two-factor experiment,i.e.,UFB water and gamma irradiation treatments,were used to determine the best seed treatment.The UFB water treatment had a significant effect on all seed germination parameters;the gamma irradiation treatment did not have a significant effect on improving the viability and vigor of the seeds,with a very low initial germination(11.7%).Soaking the seeds in UFB water for 30 min gave the best germination(51.3%).These improvements also occurred in other germination parameters such as germination rate,germination value,radicle length and vigor index.The UFB water treatment has the potential to improve the germination of seeds with low physiological qualities.

关键词： Albizia chinensis gamma rays Germination Ultrafine bubbles

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EJUSTCO:Monte Carlo radiation transport code hybrid with ANN model for gamma-ray shielding simulation

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Nuclear Science and Techniques 2023年第9期34卷 155-176页

作者： Joseph Konadu Boahen Ahmed S.G.Khalil Mohsen A.Hassan Samir A.Elsagheer Mohamed Materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)179New Borg El-Arab CityEgypt Physics Department Environmental and Smart Technology GroupFaculty of ScienceFayoum UniversityFayoum 63514Egypt Faculty of Engineering Aswan UniversityAswanEgypt

gamma ray shielding is essential to ensure the safety of personnel and equipment in facilities and environments where radiation exists.The Monte Carlo technique is vital for analyzing the gamma-ray shielding capabilities of materials.In this study,a simple Monte Carlo code,EJUSTCO,is developed to cd simulate gamma radiation transport in shielding materials for academic purposes.The code considers the photoelectric effect,Compton(incoherent)scattering,pair production,and photon annihilation as the dominant interaction mechanisms in the gamma radiation shielding problem.Variance reduction techniques,such as the Russian roulette,survival weighting,and exponential transformation,are incorporated into the code to improve computational efficiency.Predicting the exponential transformation parameter typically requires trial and error as well as expertise.Herein,a deep learning neural network is proposed as a viable method for predicting this parameter for the first time.The model achieves an MSE of 0.00076752 and an R-value of 0.99998.The exposure buildup factors and radiation dose rates due to the passage of gamma radiation with different source energies and varying thicknesses of lead,water,iron,concrete,and aluminum in single-,double-,and triple-layer material systems are validated by comparing the results with those of MCNP,ESG,ANS-6.4.3,MCBLD,MONTEREY MARK(M),PENELOPE,and experiments.Average errors of 5.6%,2.75%,and 10%are achieved for the exposure buildup factor in single-,double-,and triple-layer materials,respectively.A significant parameter that is not considered in similar studies is the gamma ray albedo.In the EJUSTCO code,the total number and energy albedos have been computed.The results are compared with those of MCNP,FOTELP,and PENELOPE.In general,the EJUSTCO-developed code can be employed to assess the performance of radiation shielding materials because the validation results are consistent with theoretical,experimental,and literary results.

关键词： Monte Carlo gamma rays Shielding Artificial neural network Simulation

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Prospective study on observations of γ-ray sources in the Galaxy using the HADAR experiment

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Frontiers of physics 2022年第6期17卷 1-14页

作者： Xiangli Qian Huiying Sun Tianlu Chen Danzengluobu Youliang Feng Qi Gao Quanbu Gou Yiqing Guo Hongbo Hu Mingming Kang Haijin Li Cheng Liu Maoyuan Liu Wei Liu Bingqiang Qiao Xu Wang Zhen Wang Guangguang Xin Yuhua Yao Qiang Yuan Yi Zhang School of Intelligent Engineering Shandong Management UniversityJinan 250357China The Key Laboratory of Cosmic rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China School of Physics and Technology Wuhan UniversityWuhan 430072China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment is a refracting terrestrial telescope array based on the atmospheric Cherenkov imaging technique.It focuses the Cherenkov light emitted by extensive air showers through a large aperture water-lens system for observing very-high-energyγ-rays and cosmic rays.With the advantages of a large field-of-view(FOV)and low energy threshold,the HADAR experiment operates in a large-scale sky scanning mode to observe galactic sources.This study presents the prospects of using the HADAR experiment for the sky survey of TeVγ-ray sources from TeVCat and provids a one-year survey of statistical significance.Results from the simulation show that a total of 23 galactic point sources,including five supernova remnant sources and superbubbles,four pulsar wind nebula sources,and 14 unidentified sources,were detected in the HADAR FOV with a significance greater than 5 standard deviations(σ).The statistical significance for the Crab Nebula during one year of operation reached 346.0σand the one-year integral sensitivity of HADAR above 1 TeV was~1.3%–2.4%of the flux from the Crab Nebula.

关键词： HADAR Galactic sources significance gamma rays

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Natural leather based gamma-ray shielding materials enabled by the coordination of well-dispersed Bi^(3+)/Ba^(2+)ions and RE_(2)O_(3)coating

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Journal of Leather Science and Engineering 2022年第1期4卷 214-224页

作者： Yue Shen Jibo Zhou Zheng Han Hao Li Linping Yan Xuepin Liao Bi Shi Department of Biomass Science and Engineering Chengdu 610065China The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education Sichuan UniversityChengdu 610065China Institute of Nuclear Science and Technology Sichuan UniversityChengdu 610065China.

gamma rays is widely used in modern science and technology,but it may cause health damage to practitioners.In the present study,natural composites based on leather and high-Z elements(atomic number≥56)were fabricated and used as gamma rays shielding materials.These shielding materials were prepared by coating rare earth nanoparticles(Er_(2)O_(3)or La2O3)onto the surface of natural leather,which was first impregnated with Bi^(3+)and Ba^(2+).Results show that the attenuation efficiency of the prepared Er1.31Bi5.46-NL(1.31 and 5.46 mmol cm^(−3)loaded elements)with thickness of 3.2 mm was 61.57%for incident rays at 121.78 keV(152Eu)and reached 96.4%in the incident of 59.5 keV(241Am),which is comparable to that of 0.25-mm lead plate(54.54 mmol cm−3).In addition,these natural-leather-based shielding materials exhibited low density(approximately 1/10 of Pb),high strength and wearable behaviors.

关键词： gamma rays Natural leather High-Z elements Rare earth elements Nanoparticles Wearability Attenuation efficiency

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Optimization and control of synchrotron emission in ultraintense laser–solid interactions using machine learning

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高功率激光科学与工程:英文版 2023年第3期11卷 15-31页

作者： J.Goodman M.King E.J.Dolier R.Wilson R.J.Gray P.McKenna SUPA Department of Physics University of StrathclydeGlasgowUK The Cockcroft Institute Sci-Tech DaresburyWarringtonUK

The optimum parameters for the generation of synchrotron radiation in ultraintense laser pulse interactions with planar foils are investigated with the application of Bayesian optimization,via Gaussian process regression,to 2D particle-incell simulations.Individual properties of the synchrotron emission,such as the yield,are maximized,and simultaneous mitigation of bremsstrahlung emission is achieved with multi-variate objective functions.The angle-of-incidence of the laser pulse onto the target is shown to strongly influence the synchrotron yield and angular profile,with oblique incidence producing the optimal results.This is further explored in 3D simulations,in which additional control of the spatial profile of synchrotron emission is demonstrated by varying the polarization of the laser light.The results demonstrate the utility of applying a machine learning-based optimization approach and provide new insights into the physics of radiation generation in laser-foil interactions,which will inform the design of experiments in the quantum electrodynamics(QED)-plasma regime.

关键词： Bayesian optimization gamma rays laser-solid interactions machine learning radiation reaction

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Preparation, characterization, and antibacterial activity of γ-irradiated silver nanoparticles in aqueous gelatin

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 403-409页

作者： Majid Darroudi Mansor B. Ahmad Mohammad Hakimi Reza Zamiri Ali Khorsand Zak Hasan Ali Hosseini Mohsen Zargar Department of Modern Sciences and Technologies School of Medicine Mashhad University of Medical Sciences Department of Chemistry Faculty of Science Universiti Putra Malaysia Chemistry Department Payame Noor University Department of Materials Engineering and Ceramic CICECO University of Aveiro Electroceramics and Materials Lab. Physics Department Faculty of Science Ferdowsi University of Mashhad Faculty of Science Qom Branch Islamic Azad University

Colloidal silver nanoparticles （Ag-NPs） were obtained through γ-irradiation of aqueous solutions containing AgNO3 and gelatin as a silver source and stabilizer, respectively. The absorbed dose of γ-irradiation influences the particle diameter of the Ag-NPs, as evidenced from surface plasmon resonance （SPR） and transmission electron microscopy （TEM） images. When the γ-irradiation dose was increased （from 2 to 50 kGy）, the mean particle size was decreased continuously as a result of γ-induced Ag-NPs fragmentation. The antibacterial properties of the Ag-NPs were tested against Methicillinresistant Staphylococcus aureus （MRSA）（Gram-positive） and Pseudomonas aeruginosa （P.a）（Gram-negative） bacteria. This approach reveals that the γ-irradiation-mediated method is a promising simple route for synthesizing highly stable Ag-NPs in aqueous solutions with good antibacterial properties for different applications.

关键词： silver nanoparticles silver nitrate gelatin gamma rays irradiation bacteria

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