Bremsstrahlung End-point Energies Research Articles

Formation of medical radioisotope 111In in photonuclear reactions

The possibility of photonuclear production of 111In radioisotope has been investigated. The enriched target 112Sn was irradiated at the linear electron accelerator LUE-75 of A. Alikhanian National Science Laboratory (Yerevan, Armenia) at the bremsstrahlung endpoint energy Eγmax = 55 MeV. The cross section per equivalent quantum for reactions 112Sn(γ,x)111In, 112Sn(γ,n)111Sn, 112Sn(γ,2n)110Sn, 112Sn(γ,3n)109Sn,112 Sn(γ,pn)110mIn, 112Sn(γ,pn)110g110In, 112Sn(γ,p2n)109In have been measured via the method of activation and off-line γ-ray spectrometric technique. The cross section per equivalent quantum of the 111In in photonuclear reaction was compared with its cross section in proton induced reaction on cadmium targets and other possible 111In production routes. It is shown that the photonuclear method can be used for the production of 111In.

Measurement of effective 98Mo(n,γ)99 Mo reaction cross-section in the epi-cadmium neutron flux produced by 10 MeV electron LINAC with Ta-BeO assembly

AbstractAn experiment was carried out to study the feasibility of 99Mo production using an electron accelerator based epi-cadmium neutron source. The neutrons were produced by the interaction of bremsstrahlung end-point energy of 10 MeV with BeO blocks and the neutrons thus produced were moderated using High Density Polyethylene blocks. Effective cross-section of 98Mo(n,γ)99Mo reaction was measured using foil activation method. An enhancement in the effective cross-section due to resonances in the epi-cadmium region was observed. The photons and neutron production/transport in the experimental set-up were simulated using the FLUKA Monte Carlo code. The simulations were found to be in good agreement with the experimental findings.

Research on natAg(γ,xn)103-106Ag reaction cross sections with the bremsstrahlung end-point energy of 70 and 75 MeV

The flux-weighted average cross sections of natAg(γ,xn)103-106Ag reactions were measured with the bremsstrahlung end-point energy of 70 and 75 MeV using an activation and off-line γ-ray spectrometric technique. The GEANT4 code was used for the simulation of the bremsstrahlung spectra. The cross sections of natAg(γ,xn) 103-106Ag reactions as a function of mono-energetic photons were theoretically calculated by using the TALYS-1.96 code. The data of the present work and literature at different bremsstrahlung end-point energy are found to be in agreement with the theoretical values within the uncertainty limit. It can be seen that the flux-weighted average cross sections of the natAg(γ,xn)105.106Ag reactions increase with bremsstrahlung energy up to the Giant Dipole Resonance region. Thereafter, a small decrease trend with the bremsstrahlung energy was seen due to the opening of another reaction channel.

Measurement of the flux-weighted average cross section for the \(^{186}\)W\((\gamma,p)^{185}\)Ta reaction at the bremsstrahlung end-point energy of 70 MeV

Abstract. The flux-weighted average cross section for the 186W(γ,p)185Ta reaction induced with 70 MeV bremsstrahlung end-point energy was measured using the activation method in combination with off-line gamma activity measurement. The 27Al(γ,2pn)24Na monitor reaction was used for the determination of the bremsstrahlung flux. The bremsstrahlung photons used to produce the photonuclear reactions were generated from a thin tungsten (W) converter by bombardment with a 70 MeV electron beam. The experimental flux-weighted average cross section is compared with the theoretical prediction, for which the absolute cross section was calculated using the TALYS 1.95 code and the bremsstrahlung spectrum was simulated using the computer program MCNPX. The present experiment was carried out at the 100 MeV electron linac of the Pohang Accelerator Laboratory, POSTECH, Pohang, Korea.

STUDY THE ISOMERIC RATIOS IN PHOTONUCLEAR EXPERIMENTS ON THE LUE-40 LINAC RDC “ACCELERATOR” NSC KIPT

The results of photoproduction of isomeric pairs from the (γ,xn) and (γ,pxn) reactions on nuclei from Zr up to Ta at the bremsstrahlung end-point energy range 30…100 MeV are systematized. Measurements were performed at the electron beam of the LUE-40 linac RDC “Accelerator” NSC KIPT using the activation method and off-line γ-ray spectrometric technique. The theoretical isomeric ratios IR for the nuclei-products of studied reactions were calculated using the cross-sections σ(E) from the TALYS1.95 code for six different level density models. The data from the international databases were additionally used to compare experimental results and theoretical predictions. The obtained results let us make conclusions about trends of values and energy dependence of IR in studied photonuclear reactions. Further directions of experimental research in the RDC “Accelerator” NSC KIPT are discussed.

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10−23 MeV

In this study, experiments were performed at bremsstrahlung end-point energies of 10−23 MeV with the beam from the MT-25 microtron using the γ-activation technique. The experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon reactions. Including isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 MeV. Therefore, taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

Production of 180m\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{180\ extrm{m}}}$$\\end{document}Hf in photoproton reaction 181\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{181}}$$\\end{document}Ta(γ,p)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(\\gamma ,p)$$\\end{document} at energy Eγmax=35\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E_{\\mathrm{\\gamma max}} = 35$$\\end{document}–95 MeV

The production of the 180mHf\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{180\ extrm{m}}\ extrm{Hf}$$\\end{document} nuclei in the photoproton reaction 181Ta(γ,p)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{181}\ extrm{Ta}}(\\gamma ,p)$$\\end{document} was studied at end-point bremsstrahlung energies Eγmax=35\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E_{\\mathrm{\\gamma max}}=35$$\\end{document}–95 MeV. The experiment was performed at the electron linear accelerator LUE-40 NSC KIPT with the use of the γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document} activation and off-line γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray spectroscopy. The experimental values of the bremsstrahlung flux-averaged cross-sections ⟨σ(Eγmax)⟩m\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\langle {\\sigma (E_{\\mathrm{\\gamma max}})}\\rangle _{\ extrm{m}}$$\\end{document} for the 181Ta(γ,p)180mHf\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{181}\ extrm{Ta}}(\\gamma ,p)^{180\ extrm{m}}\ extrm{Hf}$$\\end{document} reaction were determined, and at Eγmax>55\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E_{\\mathrm{\\gamma max}} > 55$$\\end{document} MeV obtained for the first time. The measured values, as well as the literature data, significantly (by more that an order of magnitude) exceed the theoretical flux-averaged cross-sections ⟨σ(Eγmax)⟩th\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\langle {\\sigma (E_{\\mathrm{\\gamma max}})}\\rangle _{\ extrm{th}}$$\\end{document}. The ⟨σ(Eγmax)⟩th\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\langle {\\sigma (E_{\\mathrm{\\gamma max}})}\\rangle _{\ extrm{th}}$$\\end{document} values were calculated using the cross-section σ(E)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sigma (E)$$\\end{document} computed with the TALYS1.95 code for six different level density models. A comparative analysis of the calculated total cross-sections from the TALYS computation for the reactions 181Ta(γ,p)180Hf\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{181}\ extrm{Ta}}(\\gamma ,p)^{180}\ extrm{Hf}$$\\end{document} and 181Ta(γ,n)180Ta\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${^{181}\ extrm{Ta}}(\\gamma ,n)^{180}\ extrm{Ta}$$\\end{document} was performed. It was shown that the photoproton (γ,p)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(\\gamma ,p)$$\\end{document} to photoneutron (γ,n)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(\\gamma ,n)$$\\end{document} strength ratio is consistent with the estimates based on the isospin selection rules and the value from the (e,e′p)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(e,e'p)$$\\end{document} experiment.

Investigation of (γ, xpxn)-reactions on titanium, lutetium, nickel and chromium nuclei at Ebr=37 MeV

For the first time, both the flux-weighted average yields of the 50Cr(γ,pn+2n)48V, natTi(γ,pxn)46Sc, 48Ti(γ,p)47Sc reactions and the isomeric yield ratios of the 175Lu(γ,n)174Lum,g reaction were measured at a bremsstrahlung end-point energy of 37 MeV. The flux-weighted average yields of the 52Сr(γ,n)51Cr, 58Ni(γ,n)57Ni and 58Ni(γ,p)57Co reactions were also measured and their values coincided with the results of the works of the other authors. According to the results of modeling within the framework of the TALYS-1.96 code, a significant contribution of non-statistical processes is ascertained to the mechanisms of the 48Ti(γ,p)47Sc and 50Cr(γ,pn+2n)48V reactions.

Measurement of the flux-weighted cross-sections for the natYb(γ,xn)175,169,167Yb reactions in the Bremsstrahlung end-point energies of 12–16 MeV and 60–70 MeV

Measurement of the flux-weighted cross-sections for the natYb(γ,xn)175,169,167Yb reactions in the Bremsstrahlung end-point energies of 12–16 MeV and 60–70 MeV

Isomeric pair 95 m,g Nb in the photonuclear reactions on natMo at the bremsstrahlung end-point energy of 38–93 MeV

The photonuclear reaction was studied using the electron beam from the NSC KIPT linear accelerator LUE-40. The experiment was performed using the activation and off-line γ-ray spectrometric technique. The experimental isomeric yield ratio (IR) was determined for the reaction products at the bremsstrahlung end-point energy range of 38–93 MeV. The obtained values of IR are in satisfactory agreement with the results of other studies and extend the range of previously known data. The theoretical values of the yields and the IR for the isomeric pair from the reaction were calculated using the partial cross-sections from the TALYS1.95 code for six different level density models. For the investigated range of , the theoretical dependence of IR on energy was confirmed – the IR smoothly increases with increasing energy. The comparison showed a noticeable difference (more than 3.85 times) in the experimental IR relative to all theoretical estimates.

Multiparticle natSe([formula omitted]) reactions induced with bremsstrahlung end-point energies of 20–80 MeV

The flux weighted average cross sections 〈σ〉 and cross sections per equivalent photon σq were first measured for the photonuclear multiparticle reactions natSe(γ, xnyp) at end-point bremsstrahlung gamma energies ranging from 20 to 80 MeV. The experiments were performed with the beam from the electron linear accelerator LINAC-200 with the use of the γ-activation technique. The bremsstrahlung photon flux was calculated with the program Geant4. The theoretical values of the flux weighted average cross sections 〈σ〉 and the cross sections per equivalent photon σq were calculated using the partial cross section σ(E) computed with the TALYS package code and the combined model of photonuclear reactions.

Measurement of isomeric yield ratios for 104m,gAg and 106m,gAg isotopes using bremsstrahlung end-point energies of 45–75 MeV

In this study, the isomeric yield ratio (IR) values of 104m,gAg and 106m,gAg in an natAg(γ,xn) reaction at the bremsstrahlung end-point energies (Ee) of 45, 50, 55, 60, 70, and 75 MeV were measured using an off-line gamma-ray spectrometric technique. The IR values at different bremsstrahlung end-point energies were also calculated from the cross-section data available in the TENDL-2019 library, and they were found to exhibit a similar trend with some differences in the magnitude. Herein, the IR values of 104m,gAg and 106m,gAg with the bremsstrahlung end-point energies of 70 and 75 MeV were measured for the first time. The present data were compared with those from the literature for 107,109,natAg(γ,xn), natAg(n,xn), natPd(p,xn), and 103Rh(α,xn) reactions to examine the role of the excitation energy and input angular momentum.

Theoretical consideration of isomeric ratios in some photonuclear reactions induced by bremsstrahlung with endpoint energy in giant dipole resonance region using Talys 1.95 code

Isomeric ratios of isomeric pairs produced by photonuclear reactions (γ, n) on Se, Ce, Eu and Hg targets induced by bremsstrahlung with endpoint energies in the giant dipole resonance region have been theoretically calculated using TALYS 1.95 code in combination with Geant4 simulation. The computed isomeric ratios as a function of the bremsstrahlung endpoint energies in the range of 10 to 25 MeV resulted from convolution between calculated differential cross-sections using six level density models available in TALYS 1.95 and the bremsstrahlung spectra simulated by the GEANT4 toolkit. Moreover, for each level density model, eight gamma strength functions have been employed. The calculated results are compared to the experimental data in the existing literature for Talys 1.95 model evaluation.

Measurement of the integrated cross section of 110Pd(γ,n)109mPd, 110Pd(γ,n)109gPd, and 110Pd(γ,x)108mRh reactions with 70 MeV bremsstrahlung

We measured the integrated cross sections of 110Pd(γ,n)109mPd, 110Pd(γ,n)109gPd and 110Pd(γ,x)108mRh reactions in the energy range from the reaction threshold to 70 MeV bremsstrahlung end-point energy. Measurements were performed by means of the activation method in combination with off-line γ-ray spectrometry. The induced activity of radionuclides was measured with a high-purity germanium (HPGe) detector and necessary corrections for γ-ray interferences were made. The integrated cross section of the studied reactions was measured relative to that of the monitor reaction 27Al(γ,2pn)24Na. Current results are compared with theoretical predictions using the TALYS-1.9 statistical nuclear model code. Calculations were performed using six different level density models in combination with eight γ-strength functions to determine which combinations best fit the experimental results. The present results are measured for the first time.

Yield Ratios of Isomeric Pairs \(^{196m,g}\)Au, \(^{186m,g}\)Ir, and \(^{183m,g}\)Os in the \(^{197}\)Au\((\gamma,xnyp)\) Reactions with 2.5 GeV Bremsstrahlung

The yield ratios of high to low spin states of the 196m,gAu, 186m,gIr, and 183m,gOs isomeric pairs produced by 197Au(γ,xnyp) reactions with a bremsstrahlung end-point energy of 2.5 GeV have been measured. Measurements were performed by the activation method in combination with off-line γ-ray spectrometry. The induced activity of the studied radionuclides was derived from the photo-peak area of the selected γ-ray after making the necessary corrections. The isomeric yield ratios obtained in this work are the first measurement. The relationships between the yield ratios of studied isomeric pairs with the value of high spin states, the spin difference between the high spin states and the target nucleus, and the number of nucleons emitted from the target nucleus are discussed.

Isomeric yield ratio of 115m,gCd in the 116Cd(γ,n) and 116Cd(n,2n) reactions

The isomeric yield ratio (IR) of 115m,gCd in the 116Cd(γ,n) reaction at the bremsstrahlung endpoint energies of 70 and 75 MeV and in the 116Cd(n,2n) reaction at the average neutron energies (<En > ) of 21.4 and 30.1 MeV were measured via an offline γ -ray spectrometric technique. The bremsstrahlung energies were produced by impinging the electron beam energies of 70 and 75 MeV on a thin W-target at the Pohang Accelerator Laboratory, Korea. The neutron beams were obtained from the 9Be(p,n) reaction with the proton energies of 35 and 45 MeV using the MC-50 cyclotron at the Korean Institute of Radiological and Medical Sciences. The IR values at different bremsstrahlung and neutron energies were also calculated from the cross-section values of the TENDL-2019 library based on the TALYS-1.9 code. The theoretical values agreed with the experimental data for the bremsstrahlung endpoint energies but were slightly higher for all neutron energies. The current and literature data showed that in both the 116Cd(γ,n) and 116Cd(n,2n) reactions, the IR value of 115m,gCd increases with the projectile energy, indicating the role of excitation energy. However, the experimental and theoretical IR values at the same excitation energy were significantly higher for the 116Cd(n,2n) reaction than that for the 116Cd(γ,n) reaction, highlighting the role of compound nucleus spin.

Cross-sections of photonuclear reactions 65Cu(γ, n)64Cu and 63Cu(γ, xn)63−xCu in the energy range E γmax = 35–94 MeV

The flux-averaged cross-sections for the reactions , , , and have been measured within the bremsstrahlung end-point energy range of 35–94 MeV. The experiments were performed with the electron beam from the NSC KIPT linear accelerator LUE-40 with the use of the activation and off-line γ-ray spectrometric techniques. Theoretical calculation of the flux-average cross-sections was conducted using the cross-section values from the TALYS1.95 code, run with default options. It is shown that the experimental average cross-sections for the reactions , , and are systematically higher than the theoretical estimates based on the TALYS1.95 code. The obtained values supplement the data of different laboratories for the and reactions of and . For the reaction , the values of were measured for the first time.

Multiparticle natSr(γ, ) reactions induced with bremsstrahlung end-point energies of 55, 60, and 65 MeV * *Supported by the National Research Foundation of Korea through a grant provided by the Ministry of Science and ICT (NRF-2017R1D1A1B03030484, NRF-2018R1A6A1A06024970)

This study measured the yields of the radionuclides 82Sr, 83(m+g)Sr, 85mSr, 85gSr, 87mSr, 81(g+0.976m)Rb,82mRb,83gRb,84(m+g)Rb, and 86(m+g)Rb produced in natSr(γ, xnyp) multiparticle reactions with bremsstrahlung end-point energies of 55, 60, and 65 MeV. The bremsstrahlung radiation was generated using the 100-MeV electron linear accelerator at the Pohang Accelerator Laboratory, Korea, and the reaction yields were derived from the induced activitiesmeasured using off-line γ-ray spectrometry. To obtain accurate experimental results, we performed the necessary γ-rayinterference corrections. The experimental results were compared with the theoretical predictions obtained usingthe TALYS-1.95 statistical nuclear model code. The calculations were performed using six different level-density models to ascertain which model best fitted the experimental results. The dependence of the reaction yield on the incident bremsstrahlung energy and on the number of nucleons emitted by the photonuclear reactions was also investigated.

Photo-neutron cross-section of natGd in the bremsstrahlung end-point energies of 12–16 MeV and 60–70 MeV

Photo-neutron cross-section of natGd in the bremsstrahlung end-point energies of 12–16 MeV and 60–70 MeV

Activation cross section measurements and estimation of photon and neutron induced nuclear reactions for ytterbium isotopes with covariance analysis

The cross sections of the 168Yb(n,2n)167Yb, 174Yb(n,p)174Tm, 173Yb(n,p)173Tm, 174Yb(n,α)171Er, 170Yb(n,2n)169Yb and 176Yb(n,2n)175Yb nuclear reactions at 14.77 MeV neutron energy and the flux weighted average cross sections of the 168Yb(γ,n)167Yb, 170Yb(γ,n)169Yb and 176Yb(γ,n)175Yb nuclear reactions at 10 and 15 MeV bremsstrahlung endpoint energies are measured using offline gamma spectroscopy. The bremsstrahlung photon-induced reactions are reported for the first time at these energies. The results are compared with the evaluated nuclear data from the ENDF/B.-VIII.0, JEFF-3.3 and TENDL-2019 libraries. The theoretical model calculations are performed with the TALYS-1.95 nuclear code with parameters tuned to reproduce the measured data. The measured cross sections are in good agreement with the literature and evaluated data. The results are significant for the experimental nuclear database and reactor technology development.