Browsing by Author "Aman Sharma"

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Comprehensive analysis of uncertainty quantification for the 58Ni(n, p)58Co reaction cross section
(Institute of Physics, 2024) Mahesh Choudhary; Aman Sharma; Namrata Singh; Mahima Upadhyay; Punit Dubey; A. Gandhi; Akash Hingu; G. Mishra; Sukanya De; L.S. Danu; Ajay Kumar; R.G. Thomas; Saurav Sood; Sajin Prasad; S. Mukherjee; I.N. Ruskov; Yu. N. Kopatch; A. Kumar
In this study, we measured the 58Ni(n, p)58Co reaction cross section with neutron energies of 1.06, 1.86, and 2.85 MeV. The cross section was measured using neutron activation techniques and γ-ray spectroscopy, and it was compared with cross section data available in the EXFOR. Furthermore, we calculated the covariance matrix of the measured cross section for the aforementioned nuclear reaction. The uncertainties of the theoretical calculation for 58Ni(n, p)58Co reaction cross section were calculated via Monte Carlo method. In this study, we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross sections. The theoretical calculations were performed by using TALYS-1.96. In this study, we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section. © 2024 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Deterministic sampling approach for the propagation of uncertainties in nuclear reaction models
(American Physical Society, 2022) Aman Sharma; A. Gandhi; Ajay Kumar
Uncertainty propagation of model parameters through nuclear reaction models is critical for nuclear data evaluation and other applications. Nuclear reaction models generally contain nonlinear functions of the model parameters, making the process of uncertainty propagation difficult. Usually stochastic approaches like the Monte Carlo method are employed to propagate the uncertainties through nuclear reaction models. The Monte Carlo method does provide proper results, but it takes a lot of computational power and time, which makes the process of uncertainty propagation difficult. Deterministic sampling approaches may provide results with accuracy using less computational time making the process of uncertainty propagation fast. In this study we have explored the use of a deterministic sampling approach called the unscented transform method for the uncertainty propagation in the nuclear reaction models. As a test case we have propagated the uncertainties of correlated optical model parameters through the optical model calculations for total and reaction cross sections of the n+Fe56 reaction. The results obtained using the unscented transform method are then compared with the results of the Monte Carlo method. It has been observed that the unscented transform method provides results practically similar to the Monte Carlo method in less computational time. It is concluded in this study that the unscented transform method can propagate uncertainties effectively through optical model calculations and there should be further investigation of the use of this method for other nuclear reaction models. © 2022 American Physical Society.
Erratum: 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 (Chinese Physics C (2022) 46 (014002) DOI: 10.1088/1674-1137/ac2ed4)
(Institute of Physics, 2022) A. Gandhi; Aman Sharma; Rebecca Pachuau; Namrata Singh; L.S. Danu; S.V. Suryanarayana; B.K. Nayak; A. Kumar
Experimentally measured neutron activation cross sections are presented for the 65Cu(n, α)62m Cu, 41K(n, α)38 Cl, and 65Cu(n,2n)64 Cu reactions with detailed uncertainty propagation. The neutron cross sections were measured at an incident energy of 14.92 0.02 MeV, and the neutrons were based on the t(d, n)α fusion reaction. The 27Al(n, α)24 Na reaction was used as a reference reaction for the normalization of the neutron flux. The pre-calibrated lead-shielded HPGe detector was used to detect the residues' γ-ray spectra. 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. © 2022 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Estimation of global level density parameters using an unscented transform Kalman filter technique
(American Physical Society, 2024) Mahesh Choudhary; Aman Sharma; Namrata Singh; Punit Dubey; Mahima Upadhyay; Sriya Paul; Shweta Singh; Utkarsha Mishra; A. Kumar; S. Dasgupta; J. Datta
This study focuses on estimating the level density parameters for niobium (Nb) using the unscented transform Kalman filter technique. Niobium is widely utilized in accelerator components, particularly in superconducting radiofrequency cavities. To better understand the design of accelerator components and experimental setups, accurate information on both theoretical predictions and experimental results, including the uncertainties of nuclear reactions involving niobium, is essential. In this study, we have used the unscented transform Kalman filter technique to estimate level density parameters and their correlation matrix for Nb93(α,2n)Tc95 and Nb93(α,n)Tc96 reactions through the talys nuclear code. We have used the measured experimental nuclear reaction cross sections from this study to estimate the level density parameters for the above nuclear reactions. A comprehensive analysis of uncertainty propagation has been also conducted, encompassing both theoretical predictions and experimentally measured nuclear reaction cross sections. We have calculated uncertainties in both the theoretical calculations using the Monte Carlo method and experimentally measured reaction cross sections through covariance analysis for these nuclear reactions. We have also calculated the correlation matrix of the experimentally measured cross sections for the Nb93(α,n)Tc95 and Nb93(α,n)Tc96 nuclear reactions. © 2024 American Physical Society.
Estimation of optical model parameters and their correlation matrix using Unscented Transform Kalman Filter technique
(Elsevier B.V., 2021) Aman Sharma; A. Gandhi; Ajay Kumar
In the present study, we have optimized the optical model parameters and also calculated their correlation matrix using the Unscented Transform Kalman Filter technique for the first time. We have used n+56Fe, n+45Sc and n+59Co reactions for this study in order to verify the application of this method. We have used the experimental differential cross section data for the elastically scattered neutrons from the EXFOR data library and DWBA calculations to determine the parameters. In this study we have assumed that the optical model provides correct results and the uncertainties come from the variation of fitting parameters only. We have used the TALYS nuclear reaction code for the DWBA calculations. The optical model parameters determined through this study, reproduce the calculations which are consistent with the experimental trends for the elastically scattered neutrons and total reaction cross sections. Also the correlations calculated in this work are consistent with the earlier study of n+56Fe reaction. © 2021 The Author(s)
Excitation functions of alpha-particle induced nuclear reactions on nat Sn
(Walter de Gruyter GmbH, 2024) Mahesh Choudhary; Namrata Singh; Aman Sharma; Aman Gandhi; Mahima Upadhyay; Rebecca Pachuau; Sandipan Dasgupta; Jagannath Datta; Ajay Kumar
Excitation functions of alpha-particle induced nuclear reactions on nat Sn have been presented in the 11-40 MeV energy range. In the present study, the stacked-foil activation technique followed by offline gamma-ray spectrometry was used to measure the production of 119Te, 121Te, 122Sb and 126Sb from alpha-particle induced reactions on nat Sn. The TALYS nuclear code was used to calculate the theoretical predictions of the excitation functions of nat Sn(α,x) nuclear reactions. The measured data of the above-mentioned nuclear reactions were compared with the theoretical predictions and the experimental results available from EXFOR. In this study, covariance analysis was performed to calculate the uncertainty propagation in the measured cross sections. © 2023 Walter de Gruyter GmbH, Berlin/Boston.
Exploitation of surrogate reaction method for deriving proton induced fission cross sections of short lived actinides
(Institute of Physics Publishing, 2020) Aman Sharma; A. Gandhi; Namrata Singh; S.V. Suryanarayana; B.K. Nayak; A. Kumar
In this article we have explored the possibility of measuring the proton induced fission cross sections using surrogate reaction method. To establish the validity of the surrogate method, we have derived the cross sections for 240Pu(p, f), 234Th(p, f), 236U(p, f) and 233Th(p, f) reactions using the derived cross section data of 240Am(n, f), 234Pa(n, f), 236Np(n, f) and 233Pa(n, f) reactions, which were measured by the surrogate ratio method. To extract the data, we have used the independence hypothesis of compound nucleus formation and derived a relation between proton and neutron induced fission cross sections of the consecutive isobars. The validity of the Weisskopf-Ewing approximation has been studied in detail. This study successfully confirms that the surrogate ratio method can be used to derive (p, f) cross sections of the short lived actinides. It is also concluded that a common surrogate reaction can be used for the determination of (n, f) and (p, f) cross sections for the consecutive isobars. © 2020 IOP Publishing Ltd.
Investigation of Weisskopf-Ewing approximation for the determination of (n,p) cross sections using the surrogate reaction technique INVESTIGATION of WEISSKOPF-EWING ⋯ AMAN SHARMA, A. GANDHI, and A. KUMAR
(American Physical Society, 2022) Aman Sharma; A. Gandhi; A. Kumar
The present study explores the limitations of the surrogate reaction method for determining the (n,p) cross sections for the target nuclei in the mass region A≈50 for the neutron energies 1-20 MeV. In the past few years there have been several experimental attempts for determining the (n,p) and (n,xp) cross sections using the surrogate reaction method. But this method has not been benchmarked with the experimentally well-known (n,p) cross sections. The surrogate reaction method with Weisskopf-Ewing approximation may help in providing good constraints for the cross-section data, but this approximation has not been validated yet for (n,p) reactions. In this paper, we have examined the validity of the Weisskopf-Ewing approximation for the (n,p) reactions and also check the sensitivity of the surrogate reaction results with respect to the compound nucleus spin distribution. We have simulated the cross sections obtained through the surrogate reaction method for n+Ti48, n+Cr53, n+Fe56, and n+Co59 reactions for the different schematic spin distributions of the compound nucleus and studied the effect of assuming the validity of the Weisskopf-Ewing approximation. It has been observed that the proton decay probabilities of the compound nucleus for the (n,p) channel are strongly spin dependent, therefore the Weisskopf-Ewing approximation is violated. We have also observed that the cross sections obtained using the Weisskopf-Ewing approximation show clear dependence on the spin distribution of the compound nucleus. It has also been observed that, due to the large pre-equilibrium contributions in the (n,p) reactions at higher neutron energies, the use of the surrogate reaction method for the neutron energies greater than ≈15 MeV may not be suitable. It is concluded that the surrogate reaction method relying solely on the Weisskopf-Ewing approximation is not sufficient for determining the (n,p) cross sections for the target nuclei in mass range A≈50 and further development and exploration of the surrogate technique is required. © 2022 American Physical Society.
Learning correlations in nuclear masses using neural networks
(American Physical Society, 2022) Aman Sharma; A. Gandhi; Ajay Kumar
There have been great improvements in the predictions of nuclear masses, yet it is difficult to exactly reproduce the measured nuclear mass. It has been suggested that the cause of such discrepancies is due to the negligence of many-body effects in the available theoretical models. The errors in the prediction of the nuclear mass show residual correlations due to the missing physics in the mass models. In the present Letter we have tried to learn such correlations by using the neural networks. We have used a neural network architecture which adaptively learns the linear and nonlinear correlations between the data of different fidelity. We have used the theoretical predictions of finite range droplet model and Hartree-Fock-Bogoliubov models in the input of the neural networks. The present approach show significant improvements in the accuracy of the predictions. It has been clearly presented that the difference between the predictions from the present approach and the experimental data behave more, such as white noise, showing that using the present approach the residual correlations arising due to the missing physics from the available mass models can be learned. © 2022 American Physical Society.
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
(Institute of Physics, 2022) A. Gandhi; Aman Sharma; Rebecca Pachuau; Namrata Singh; L.S. Danu; S.V. Suryanarayana; B.K. Nayak; A. Kumar
Experimentally measured neutron activation cross sections are presented for the 65Cu(n,α)62mCu, 41K(n,α)38Cl, and 65Cu(n,2n) 64Cu reactions with detailed uncertainty propagation. The neutron cross sections were measured at an incident energy of 14.92 ± 0.02 MeV, and the neutrons were based on the t(d,n)α fusion reaction. The 27Al(n,α)naNa reaction was used as a reference reaction for the normalization of the neutron flux. The pre-calibrated lead-shielded HPGe detector was used to detect the residues' γ-ray spectra. 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. © 2022 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Measurement of (n,γ), (n,p), and (n,2n) reaction cross sections for sodium, potassium, copper, and iodine at neutron energy 14.92±0.02 MeV with covariance analysis MEASUREMENT of (N,γ), (N,P), and (n,2n) REACTION ... A. GANDHI et al.
(American Physical Society, 2020) A. Gandhi; Aman Sharma; A. Kumar; Rebecca Pachuau; B. Lalremruata; S.V. Suryanarayana; L.S. Danu; Tarun Patel; Saroj Bishnoi; B.K. Nayak
The cross section of the Na23(n,γ)Na24, K41(n,p)Ar41, Cu65(n,p)Ni65, and I127(n,2n)I126 reactions have been measured at 14.92±0.02 MeV neutron energy through neutron activation method followed by off-line γ-ray spectrometry. Al27(n,α)Na24 is used as a reference reaction for the neutron flux normalization. The neutron beam was produced via the H3(d,n) fusion reaction. Detailed uncertainty propagation has been performed using the covariance analysis and the measured cross sections are being reported with their uncertainties and correlation matrix. The cross sections measured in the present work are compared with the earlier reported cross sections available in the EXFOR database. Furthermore, theoretical calculations have been performed using the empire-3.2 and talys-1.9 codes with RIPL-3 parametrization, from reaction threshold to 20 MeV. The present experimental cross sections are also compared with the evaluated nuclear data from TENDL-2017, JENDL-4.0, and ENDF/B-VIII.0. In the case of (n,γ) and (n,2n) reactions, the comparison is also made with the IRDFF-1.05 evaluation. © 2020 American Physical Society.
Measurement of alpha-induced reaction cross-sections for natZn with detailed covariance analysis
(Elsevier B.V., 2023) Mahesh Choudhary; Aman Sharma; Namrata Singh; A. Gandhi; S. Dasgupta; J. Datta; K. Katovsky; A. Kumar
The production cross-section of 68Ge, 69Ge, 65Zn and 67Ga radioisotopes from alpha-induced nuclear reaction with natZn have been measured using the stacked foil activation technique followed by the off-line γ-ray spectroscopy in the incident alpha energy range 14-37 MeV. The obtained nuclear reaction cross-sections are compared with previous experimental data available in the EXFOR data library, evaluated nuclear data from TENDL-2019 and theoretical results, calculated using TALYS nuclear reaction code. We have also performed the detailed uncertainty analysis for these nuclear reactions and their respective correlation metrics are presented. Since α-induced reactions are important in nuclear medicine and developing the nuclear reaction codes so needful corrections related to the coincidence summing factor and the geometric factor have been considered during the data analysis in the present study. © 2023 Elsevier B.V.
Measurement of alpha-induced reaction cross-sections on nat Mo with detailed covariance analysis
(Springer Science and Business Media Deutschland GmbH, 2022) Mahesh Choudhary; A. Gandhi; Aman Sharma; Namrata Singh; Punit Dubey; Mahima Upadhyay; S. Dasgupta; J. Datta; A. Kumar
In the present study we have measured the excitation functions for the nuclear reactions natMo(α,x)103Ru, natMo(α,x)97Ru, natMo(α,x)95Ru, natMo(α,x)96gTc, natMo(α,x)95gTc and natMo(α,x)94gTc in the energy range 9–32 MeV. We have used the stacked foil activation technique followed by the offline gamma-ray spectroscopy technique to measure the excitation functions. In this study we have also documented detailed uncertainty analysis for these nuclear reactions and their corresponding covariance matrix are also presented. The excitation functions are compared with the available experimental data from EXFOR data library and the theoretical prediction from TALYS nuclear reaction code. © 2022, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.
Measurement of excitation functions for natCu(α, x) reactions with detailed covariance analysis
(Institute of Physics, 2023) Mahesh Choudhary; Aman Sharma; A. Gandhi; Namrata Singh; Punit Dubey; Mahima Upadhyay; Utkarsha Mishra; N.K. Dubey; S. Dasgupta; J. Datta; K. Katovsky; A. Kumar
The excitation functions of 66Ga, 67Ga, 65Zn and 64Cu radioisotopes produced via alpha-induced reaction on nat Cu were measured using a stacked foil activation method. The gamma-ray activity produced by the above mentioned radionuclides was measured using the HPGe detector. The covariance analysis was performed to quantify the measured cross-section uncertainties as well as the correlation between different alpha energy cross-sections. A covariance matrix and cross-sections for the natCu(α, x)66Ga, natCu(α, x)67Ga, natCu(α, x)65Zn and natCu(α, x)64Cu nuclear reactions in the projectile energy range of 15-37 MeV are reported in the present work. The measured reaction cross-sections are compared with the existing experimental data and theoretically simulated results from the TALYS code. © 2022 IOP Publishing Ltd.
Measurement of neutron induced reaction cross-section of 99Mo
(Institute of Physics, 2023) Mahima Upadhyay; Mahesh Choudhary; Namrata Singh; A. Gandhi; Aman Sharma; Sumit Bamal; Akash Hingu; S. Mukherjee; G. Mishra; Sukanya De; L.S. Danu; Saurav Sood; Sajin Prasad; Ajay Kumar; R.G. Thomas; A. Kumar
In the present work, we have measured 98Mo(n,γ)99Mo reaction cross-section using a 7Li(p,n)7Be neutron source at 1.67 ± 0.14, 2.06 ± 0.14 and 2.66 ± 0.16 MeV neutron energies. We have employed offline γ-ray spectroscopy to measure the induced activity of the sample. The 115In(n,n’γ)115mIn reaction was used as a monitor reaction. Different attributes propagating the uncertainty in the total result, measured cross-sections with their uncertainties and correlation coefficients are given in detail in the present study. The result is compared with the data libraries, EXFOR database and theoretical model outcome from different level density models. © 2023 IOP Publishing Ltd.
Measurement of the excitation functions for natNi(α,x), reactions with detailed covariance analysis
(Springer, 2024) Namrata Singh; Mahesh Choudhary; A. Gandhi; Aman Sharma; Mahima Upadhyay; Punit Dubey; Rebecca Pachuau; S. Dasgupta; J. Datta; A. Kumar
We measured production cross sections of (Formula presented.) Co, (Formula presented.) Co, (Formula presented.) Co, (Formula presented.) Zn and (Formula presented.) Cu radioisotopes from (Formula presented.) -induced reactions of (Formula presented.) Ni by using a stacked-foil activation technique and offline (Formula presented.) -ray spectroscopy technique. The results were compared with the available experimental data as well as the theoretical calculations based on the TALYS (Formula presented.) 1.9 code. The present results in the energy region from 19 MeV to 40 MeV are in consistent with the existing experimental data and the calculated results. The measured cross-sections are reported along with their uncertainties and covariance matrix after a thorough uncertainty propagation using covariance analysis. The present experimental results will significantly contribute to enlarging the literature database for (Formula presented.) -induced reactions on (Formula presented.) Ni, leading to a variety of applications. © The Author(s), under exclusive licence to Società.
Measurements of neutron capture cross sections on109Ag at 0.53, 1.05, 1.66 MeV
(Institute of Electrical and Electronics Engineers Inc., 2023) Mahima Upadhyay; Mahesh Choudhary; Aman Gandhi; Namrata Singh; Sumit Bamal; Aman Sharma; Ajay Kumar; Akash Hingu; Sukanaya De; R.G. Thomas; Ajay Kumar; L.S. Danu; G. Mishra; A. Mitra; K. Katovsky; S. Mukherjee; Saurav Sood; Sajin Prasad
The cross section of the 109Ag(n,γ)110mAg reaction is measured with the aid of using the neutron activation approach and γ-ray spectroscopy. Neutrons were generated with the help of using the 7Li(p,n) reaction. The neutron flux was measured using the 115In(n,n')115mIn monitor reaction. The cross-section results were described along with the absolute errors, by uncertainty propagation, using the covariance technique. The corrections for γ-ray true coincidence summing, γ-ray self-attenuation were executed. © 2023 IEEE.
Neutron capture reaction cross section measurement for iodine nucleus with detailed uncertainty quantification
(Springer Science and Business Media Deutschland GmbH, 2021) A. Gandhi; Aman Sharma; Rebecca Pachuau; Namrata Singh; Prashant N. Patil; Mayur Mehta; L.S. Danu; S.V. Suryanarayana; B.K. Nayak; B. Lalremruata; A. Kumar
The neutron activation cross section for 127I(n,γ)128I reaction has been experimentally measured with respect to the 115In(n,inl)115Inm reference monitor reaction cross section in the neutron spectrum average energy range 0.60- - 2.51 MeV. The neutrons were produced through 7Li(p,n)7Be reaction, and γ-ray spectra of the residue product were measured offline with the precalibrated lead-shielded HPGe detector. The very first time the covariance analysis was done to quantify the measured cross section uncertainties and the correlation coefficients between the different neutron energy cross sections for iodine nucleus. The needful corrections related to the γ-ray self-attenuation process, γ-ray true coincidence summing effect and the low background neutron energy contributions were considered in the present measurement. Theoretical calculations were done using the standard nuclear reaction model codes TALYS-1.9 and EMPIRE-3.2 to obtain the 127I(n,γ)128I reaction cross section. The measured cross sections were compared with the experimental data available in the EXFOR database, theoretical predicted results, and ENDF/B-VIII.0, JEFF-3.1/A, TENDL-2019, and JENDL-4.0 evaluated nuclear data. © 2021, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.
Neutron radiative capture cross section for sodium with covariance analysis
(Springer Science and Business Media Deutschland GmbH, 2021) A. Gandhi; Aman Sharma; Rebecca Pachuau; B. Lalremruata; Mayur Mehta; Prashant N. Patil; S.V. Suryanarayana; L.S. Danu; B.K. Nayak; A. Kumar
The neutron radiative capture cross sections measurement has been carried out for the 23Na nucleus in the neutron energy region from 0.6 to 3.2 MeV using the neutron activation technique followed by off-line γ-ray spectrometry. The measurement was made relative to the 115In(n,n′ γ)115In m reference monitor reaction cross section. The neutrons were produced via the 7Li(p,n)7Be reaction. Detailed uncertainty propagation has been performed using the covariance analysis, and the measured cross sections are being reported with their uncertainties, covariance, and correlation matrix. The necessary corrections have been made for the low background neutron energy contribution, γ-ray true coincidence summing, and self-attenuation process. The obtained neutron spectrum averaged cross sections of 23Na(n,γ)24Na are discussed and compared with the existing cross sections data retrieved from the EXFOR database. EMPIRE-3.2 and TALYS-1.9 calculations were performed in order to determine the radiative capture cross section in this energy region. The present results are also compared with the evaluated nuclear data from ENDF/B-VIII.0, TENDL-2019, IRDFF-1.05, JENDL-4.0, and JEFF-3.3. The obtained cross section results are in good agreement with existing experimental data, evaluated libraries, and reaction models for the highest energy points (2.11 and 3.13 MeV), while the lowest-energy point at 0.61 MeV underestimates them. © 2021, Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.
Study of the surrogate ratio method by determination of 56Fe(n,xp) cross sections
(Elsevier B.V., 2024) Aman Sharma; Punit Dubey; Utkarsha Mishra; Nitin Dubey; Jyoti Pandey; Ramandeep Gandhi; A. Pal; Abhijit Baishya; T. Santhosh; P.C. Rout; B.K. Nayak; S. Santra; A. Chakraborty; A. Kumar
In recent years (n,xp) cross sections of some long-lived radionuclei which are of importance in the upcoming fusion reactor technologies have been constrained using the surrogate ratio method. But the (n,xp) cross sections for the stable nuclei for which a great wealth of data is available from the direct measurements have not been constrained using surrogate ratio method yet, so that the consistency of the surrogate ratio method can be checked. In this study we have investigated the validity of surrogate ratio method by constraining 56Fe(n,xp) cross sections and then the results are compared with the available experimental data, evaluated data and the statistical model predictions. In this study 52Cr(n,xp) reaction has been used as the reference reaction in the surrogate ratio method. It is found in this study that (n,xp) cross sections constrained using surrogate ratio method are sensitive to the spin distribution of the compound nuclei populated in the surrogate reactions. It is also presented in this study that the proton emission probabilities for 57Fe and 53Cr are highly spin dependent. It is concluded that the surrogate ratio method is not suitable for constraining the (n,xp) cross sections. © 2023 The Authors