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Investigation of 58Ni(n, p)58Co reaction cross-section with covariance analysis

Chinese Physics C 2024年第2期48卷 78-90页

作者： Akash Hingu S.Mukherjee Siddharth Parashari Arora Sangeeta A.Gandhi Mahima Upadhyay Mahesh Choudhary Sumit Bamal Namrata Singh G.Mishra Sukanya De Saurav Sood Sajin Prasad G.Saxena Ajay Kumar R.G.Thomas B.K.Agrawal K.Katovsky A.Kumar Department of Physics Faculty of ScienceThe M.S.University of BarodaVadodara 390002India Faculty of Electrical Engineering and Communication Brno University of TechnologyBrnoCzech Republic Department of Physics Faculty of ScienceUniversity of ZagrebBijenička c.32Zagreb 10000Croatia Department of Physics University Institute of SciencesChandigarh UniversityGharuanMohali 140413PunjabIndia Department of Physics Banaras Hindu UniversityVaranasi 221005India Horia Hulubei National Institute for Physics and Nuclear Engineering Măgurele 077125Romania Nuclear Physics Division Bhabha Atomic Research CentreMumbai 400085India Health Physics Division Bhabha Atomic Research CentreMumbai 400085India Department of Physics(H&S) Government Women Engineering CollegeAjmer 305002India Saha Institute of Nuclear Physics Kolkata 700064India Homi Bhabha National Institute Anushakti NagarMumbai 400094India

The excitation function of the 58Ni(n,p)58Co reaction was measured using the well-established neutron activation technique andγ-ray spectroscopy.Neutrons in the energy range of 1.7 to 2.7 MeV were generated using the 7Li(p,n)reaction.The neutron flux was measured using the standard 115In(n,n’)115mIn monitor reaction.The results of the neutron spectrum averaged cross-section of 58Ni(n,p)58Co reactions were compared with existing cross-section data available in the EXFOR data library as well as with various evaluated data libraries such as ENDF/B-VIII.0,JEFF-3.3,JENDL-4.0,and CENDL-3.2.Theoretical calculations were performed using the nuclear reaction code TALYS.Various nuclear level density(NLD)models were tested,and their results were compared with the present findings.Realistic NLDs were also obtained through the spectral distribution method(SDM).The cross-section results,along with the absolute errors,were obtained by investigating the uncertainty propagation and using the covariance technique.Corrections forγ-ray true coincidence summing,low-energy background neutrons,andγ-ray self attenuation were performed.The experimental cross-section obtained in the present study is consistent with previously published experimental data,evaluated libraries,and theoretical calculations carried out using the TALYS code.

关键词： nuclear reactions (n,p)reaction cross-section measurement covariance analysis nuclear level density

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covariance analysis of periodic and quasi-periodic orbits around Phobos with applications to the Martian Moons eXploration mission

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Astrodynamics 2023年第3期7卷 363-379页

作者： Edoardo Ciccarelli Nicola Baresi Surrey Space Centre University of SurreyGU27XHGuildfordUK

Understanding the internal composition of a celestial body is fundamental for formulating theories regarding its origin.Deep knowledge of the distribution of mass under the body’s crust can be achieved by analyzing its moments of inertia and gravity field.In this regard,the two moons of the Martian system have not yet been closely studied and continue to pose questions regarding their origin to the space community;thus,they deserve further characterization.The Martian Moons eXploration mission will be the first of its kind to sample and study Phobos over a prolonged period.This study aims to demonstrate that the adoption of periodic and quasi-periodic retrograde trajectories would be beneficial for the scientific value of the mission.Here,a covariance analysis was implemented to compare the estimation of high-order gravitational field coefficients from different orbital geometries and for different sets of processed observables.It was shown that the adoption of low-altitude non-planar quasi-satellite orbits would help to refine the knowledge of the moon’s libration angle and gravitational field.

关键词： covariance analysis Martian system geodetic navigation Martian Moons eXploration(MMX) Phobos

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Measurement of the(n,2n)reaction cross-sections of iodine and cesium induced by D-T neutrons with covariance analysis

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中国物理C:英文版 2023年第9期47卷 86-94页

作者：兰长林牛玉鑫魏玉婷陆芳潇杨宪林续瑞瑞张玥葛裕杰王家豪姜功 School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China China National Nuclear Corporation Beijing 100045China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China

The cross-sections of the 127I(n,2n)126I and 133Cs(n,2n)132Cs reactions at neutron energies of 13.83±0.05,14.33±0.10,and 14.79±0.10 MeV were measured relative to the 93Nb(n,2n)92mNb reaction using the activation technique in combination with off-lineγ-ray spectrometry.A neutron beam was generated from the T(d,n)4He reaction using the K-400 neutron generator at the China Academy of Engineering Physics.Considering the correlations between different attributes,detailed uncertainty propagation was performed using covariance analysis,and the cross-sections were reported with their uncertainties and correlation matrix.The uncertainty of the measurement cross-sections ranged from 4.84 to 5.90%,which is lower than previous experimental data.Furthermore,the theoretical excitation functions of the 127I(n,2n)126I and 133Cs(n,2n)132Cs reactions were calculated using the TALYS-1.95 and EMPIRE-3.2.3 codes.Then,the experimentally determined cross-sections were analyzed by comparing them with literature data available in the EXFOR database and evaluated nuclear data in the ENDF/B-VIII.0,JEFF-3.3,JENDL-5,BROND-3.1,CENDL-3.2,and TENDL-2021 databases.Compared with the values previously reported in the 13.8-14.8 MeV energy region,the precision of the results obtained in this study was greatly improved.The current experimental results with thorough uncertainties and covariance information are critical for verifying the reliability of the theoretical model and improving the quality of the nuclear database.

关键词： 127I(n,2n)126I 133Cs(n,2n)132Cs cross-section neutron activation covariance analysis excitation function

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Measurement of^(134)Xe(n,2n)^(133m),gXe reaction cross sections in 14‑MeV region with detailed uncertainty quantification

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Nuclear Science and Techniques 2023年第1期34卷 33-42页

作者： Jun‑Hua Luo Jun‑Cheng Liang Li Jiang Fei Tuo Liang Zhou Long He Institute of New Energy Hexi UniversityZhangye 734000China School of Physics and Electromechanical Engineering Hexi UniversityZhangye 734000China National Institute of Metrology Beijing 100029China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China China CDC National Institute for Radiological ProtectionBeijing 100088China

A lead-shielded HPGe detector and offlineγ-ray spectra of the residual product were used to measure the cross section(CS)and ratios of isomeric CS(σm/σg)in^(134)Xe(n,2n)^(133m),gXe reactions at different energies(13.5 MeV,13.8 MeV,14.1 MeV,14.4 MeV,14.8 MeV)relative to the^(93)Nb(n,2n)^(92)mNb reaction CS.The target was high-purity natural Xe gas under high pressure.The T(d,n)4He reaction produces neutrons.TALYS code(version 1.95)for nuclear reactions was used for calculations,with default parameters and nuclear level density models.The uncertainties in the measured CS data were thoroughly analyzed using the covariance analysis method.The results were compared with theoretical values,evaluation data,and previous experimental findings.CS data of the 134Xe(n,2n)133mXe and 134Xe(n,2n)133gXe reactions and the corresponding isomeric CS ratios at 13.5 MeV,13.8 MeV,and 14.1 MeV neutron energies are reported for the first time.This research advances our knowledge of pre-equilibrium emission in the(n,2n)reaction channel by resolving inconsistencies in the Xe data.

关键词： ^(134)Xe(n,2n)reactions 14-MeV neutrons Cross sections(CSs) Isomeric ratios(IRs) covariance analysis

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New cross-section measurements for the (n, 2n), (n, p), and (n, a) reactions on bromine in the 14 MeV region with detailed uncertainty quantification

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Chinese Physics C 2023年第3期47卷 93-106页

作者：贺龙罗均华蒋励 School of Physics and Electromechanical Engineering Hexi UniversityZhangye 734000China Institute of New Energy Hexi UniversityZhangye734000China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

Measurement of the cross-sections of the ^(79)Br(n,2n)^(78)Br,^(81)Br(n,p)^(81)mSe,^(81)Br(n,α)^(78)As,and ^(79)Br(n,α)^(76)As reactions was performed at specific neutron energies,precisely,13.5±0.2,14.1±0.2,14.4±0.2,and 14.8±0.2 MeV,relative to the standard ^(93)Nb(n,2n)^(92)mNb and ^(27)Al(n,α)^(24)Na reference reactions using offlineγ-ray spectrometry and neutron activation.Monoenergetic neutrons were generated at the China Academy of Engineering Physics via a ^(3)H(d,n)^(4)He reaction using the K-400 Neutron Generator equipped with a solid ^(3)H-Ti based target.The activity of the reaction produce was obtained using a high-purity germanium detector.The cross-sections of the(n,2n),(n,p),and(n,α)reactions on the bromine isotopes were measured in the 13–15 MeV neutron energy range.The covariance analysis approach was employed for a thorough inspection of any uncertainties within the measured cross-section data.A discussion and comparison of the observed outcome were carried out with previously published data,especially with the results of the JENDL-4.0,JEFF-3.3,TENDL-2019,and ENDF/B-VIII.0 data libraries,along with the theoretical excitation function curve derived by employing the TALYS-1.95 program.Improved cross-section restrictions for the investigated processes in the 13–15 MeV neutron energy range will be obtained using the current findings,which will help to raise the caliber of associated databases.Furthermore,the parameters of relevant nuclear reaction models can be verified using this data.

关键词： ^(79,81)Br sotopes 4 MeV neutron (n,2n) (n,p) and(n,a)reactions crss-section covariance analysis

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Systematic study of the(n,2n)reaction cross section for^(121)Sb and^(123)Sb isotopes

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Chinese Physics C 2022年第5期46卷 77-94页

作者： R.K.Singh N.L.Singh R.D.Chauhan Mayur Mehta S.V.Suryanarayana Rajnikant Makwana B.K.Nayak H.Naik Tarak Nath Nag K.Katovsky Department of Physics Faculty of Sciencethe M.S.University of BarodaVadodara-390002INDIA Department of Physics Netaji Subhas University of TechnologyDwarkaNew Delhi-110078INDIA Institute for Plasma Research Gandhinagar-382428INDIA Nuclear Physics Division Bhabha Atomic Research CentreMumbaiINDIA Radiochemistry Division Bhabha Atomic Research CentreMumbaiINDIA Department of Electrical Power Engineering Brno University of TechnologyBrno-61600Czech Republic

The cross sections of the^(121)Sb(n,2n)^(120)Sb^(m) and ^(123)Sb(n,2n)^(122)Sb reactions were measured at 12.50,15.79 and 18.87 MeV neutron energies relative to the standard ^(27)Al(n,α)^(24)Na monitor reaction using neutron activation and offline γ-ray spectrometry.Irradiation of the samples was performed at the BARC-TIFR Pelletron Linac Facility,Mumbai,India.The quasi-monoenergetic neutrons were generated via the ^(7)Li(p,n)reaction.Statistical model calculations were performed by nuclear reaction codes TALYS(ver.1.9)and EMPIRE(ver.3.2.2)using various input parameters and nuclear level density models.The cross sections of the ground and the isomeric state as well as the isomeric cross section ratio were studied theoretically from reaction threshold to 26 MeV energies.The effect of pre-equilibrium emission is also discussed in detail using different theoretical models.The present measured cross sections were discussed and compared with the reported experimental data and evaluation data of the JEFF-3.3,ENDF/B-VIII.0,JENDL/AD-2017 and TENDL-2019 libraries.A detailed analysis of the uncertainties in the measured cross section data was performed using the covariance analysis method.Furthermore,a systematic study of the(n,2n)reaction cross section for^(121)Sb and^(123)Sb isotopes was also performed within 14-15 MeV neutron energies using various systematic formulae.This work helps to overcome discrepancies in Sb data and illustrate a better understanding of pre-equilibrium emission in the(n,2n)reaction channel.

关键词： antimony (n,2n)reaction cross section 7Li(p,n)reaction neutron source neutron activation and offlineγ-ray spectrometry systematic formulae covariance analysis TALYS(ver.1.9)and EMPIRE(ver.3.2.2)codes

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Measurement of(n,α)and(n,2n)reaction cross sections at a neutron energy of 14.92±0.02 MeV for potassium and copper with uncertainty propagation

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Chinese Physics C 2022年第1期46卷 110-117页

作者： A.Gandhi Aman Sharma Rebecca Pachuau1 Namrata Singh L.S.Danu S.V.Suryanarayana B.K.Nayak A.Kumar Department of Physics Banaras Hindu UniversityVaranasi 221005India Nuclear Physics Division Bhabha Atomic Research CentreMumbai 400085India

Experimentally measured neutron activation cross sections are presented for the ^(65)Cu(n,0)^(62m)Cu,^(41) K(n,a)^(38C)l,and ^(65)Cu(n.2n)^(64)Cu reactions with detailed uncertainty propagation.The neutron cross secions were measured at an incident energy of 14.92±0.02 MeV,and the neutrons were based on the(d,n)a fusion reaction.The ^(27) Al(n,a)^(24)Na reaction was used as a reference reaction for the normalization of the neutron flux.The pre-calib-rated lead-shielded HPGe detector was used to detect the residues'γ-ray spetra.The data from the measured cross sections are compared to the previously measured cross sections from the EXFOR database,theoretically calculated cross sections using the TALYS and EMPIRE codes,and evaluated nuclear data.

关键词： nuclear reactions (n,a)and(n,2n)reactions t(c/,n)a neutron source uncertainty propagation covariance analysis TALYS-1.9 and EMPIRE-3.2 code

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14.77 MeV neutron-induced nuclear reaction cross sections for zinc,yttrium,and molybdenum targets

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Chinese Physics C 2023年第3期47卷 107-126页

作者： T.S.Ganesapandy G.T.Bholane S.H.Patil S.S.Dahiwale V.N.Bhoraskar S.D.Dhole Department of Physics Savitribai Phule PuneUniversityPune 411007India

The cross sections for neutron-induced nuclear reactions on natural zinc, yttrium, and molybdenum targets were measured at a neutron energy of 14.77 ± 0.17 MeV using the activation technique, offline gamma-ray spectrometry, and a detailed covariance analysis. The uncertainty in the statistical model calculations of cross sections for the (n, 2n), (n, p), (n, α), and (n, γ) reactions with natural zinc, yttrium, and molybdenum at neutron energies from 13 to 17 MeV was calculated using the TALYS-1.96 nuclear code. The measured cross sections of the present study were compared with the experimental cross sections reported in the EXFOR database, the cross sections were calculated with the TALYS-1.96 and EMPIRE-3.2.3 nuclear codes and the evaluated nuclear data from the TENDL-2019, JENDL-5, and ENDF/B-VIII.0 libraries.

关键词： cross section activation analysis covariance analysis TALYS EMPIRE

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Parametric Methods for the Regional Assessment of Cardiac Wall Motion Abnormalities: Comparison Study

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Computers, Materials & Continua 2021年第10期69卷 1233-1252页

作者： Narjes Benameur Mazin Abed Mohammed Ramzi Mahmoudi Younes Arous Begonya Garcia-Zapirain Karrar Hameed Abdulkareem Mohamed Hedi Bedoui University of Tunis El Manar Higher Institute of Medical Technologies of TunisLaboratory of Biophysics and Medical TechnologiesTunisTunisia College of Computer Science and Information Technology University of Anbar31001AnbarIraq Faculty of Medicine of Monastir Medical Imaging Technology Lab-LTIM-LR12ES06University of Monastir5019MonastirTunisia Gaspard-Monge Computer-Science Laboratory Paris-Est UniversityMixed Unit CNRS-UMLV-ESIEE UMR8049BP99ESIEE Paris CitéDescartes93162 Noisy Le GrandFrance Military Hospital of Instruction of Tunis TunisTunisia eVIDA Lab University of DeustoAvda/Universidades 24Bilbao48007Spain College of Agriculture Al-Muthanna UniversitySamawah66001Iraq

Left ventricular(LV)dysfunction is mainly assessed by global contractile indices such as ejection fraction and LV Volumes in cardiac MRI.While these indices give information about the presence or not of LV alteration,they are not able to identify the location and the size of such alteration.The aim of this study is to compare the performance of three parametric imaging techniques used in cardiac MRI for the regional quantification of cardiac dysfunction.The proposed approaches were evaluated on 20 patients with myocardial infarction and 20 subjects with normal function.Three parametric images approaches:covariance analysis,parametric images based on Hilbert transform and those based on the monogenic signal were evaluated using cine-MRI frames acquired in three planes of views.The results show that parametric images generated from the monogenic signal were superior in term of sensitivity(89.69%),specificity(86.51%)and accuracy(89.06%)to those based on covariance analysis and Hilbert transform in the detection of contractile dysfunction related to myocardial infarction.Therefore,the parametric image based on the monogenic signal is likely to provide additional regional indices about LV dysfunction and it may be used in clinical practice as a tool for the analysis of the myocardial alterations.

关键词： covariance analysis cardiac MRI monogenic signal assessment Hilbert transform

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Analytic Initial Relative Orbit Solution for Angles-Only Space Rendezvous Using Hybrid Dynamics Method

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 221-234页

作者： Baichun Gong Shuang Li Lili Zheng Jinglang Feng Nanjing University of Aeronautics and Astronautics Nanjing210016China Beijing Institute of Aerospace System Engineering Beijing100076China University of Strathclyde GlasgowG11XQScotland

A closed-form solution to the angles-only initial relative orbit determination(IROD)problem for space rendezvous with non-cooperated target is developed,where a method of hybrid dynamics with the concept of virtual formation is introduced to analytically solve the problem.Emphasis is placed on developing the solution based on hybrid dynamics(i.e.,Clohessy-Wiltshire equations and two-body dynamics),obtaining formation geometries that produce relative orbit state observability,and deriving the approximate analytic error covariance for the IROD solution.A standard Monte Carlo simulation system based on two-body dynamics is used to verify the feasibility and evaluate the performance proposed algorithms.The sensitivity of the solution accuracy to the formation geometry,observation numbers is presented and discussed.

关键词： Space rendezvous relative orbit determination angles-only measurement covariance analysis

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