عنوان مقاله [English]
The Isomeric Yield Ratio (IYR) of 115m,gCd in the 40, 45, 50, 55, 60, 65, 70 and 75 MeV bremsstrahlung induced reaction of natCd has been determined for the first time by off-line gamma ray spectrometric technique using 100 MeV electron linac at Pohang Accelerator Laboratory (PAL), Pohang, Korea. The IYR of 115m,gCd as a function of bremsstrahlung energy was also calculated theoretically using computer code TALYS 1.6. The experimental IYR in the 116Cd(γ,n)115m,gCd reaction obtained in the present work along with literature data at lower energies are compared with the theoretical value from TALYS and found to be in general agreement. It was observed that the experimental and theoretical IYR of 115m,gCd increases with the increase of end-point bremsstrahlung energy, which shows the effect of excitation energy. It was also seen that the IYR of 115m,gCd increases sharply from the reaction threshold value to end-point bremsstrahlung energy of 18 MeV and thereafter increase slowly. This indicates the role of Giant Dipole Resonance (GDR) besides the effect of excitation energy.
 I.B. Haller, G. Rudstam, Rerative yields of the isomeric pairs 69gZn-69mZn and 52gMn-52mMn in some spallation reactions induced by 20-153 MeV protons, Journal of Inorganic and Nuclear Chemistry 19 (1961) 1-8.
 J.R. Huizenga, R. Vandenbosch, Interpretation of isomeric cross-section ratios for (n,γ) and (γ,n) reactions, Physical Review 120 (1960) 1305-1312.
 C.T. Bishop, J.R. Huizenga, J.P. Hummel, Isomer ratios from (α, xn) reactions on silver, Physical Review 135 (1964) B401-B411.
 R. Vandenbosch, L. Haskin, J.C. Norman, Isomer ratios for Y87,87m and the spin dependence of the nuclear level density, Physical Review 137 (1965) B1134-B1144.
 M. Tatari, G.N. Kim, H. Naik, K.S. Kim, S.C. Yang, M. Zaman, S.G. Shin,Y-U. Kye, M-H. Cho, Measurement of Isomeric yield ratios of 86m,gY, 87m,gY and 89m,gZr in the photonuclear reactions of 89Y and natZr at the end-point bremsstrahlung energies of 45 and 55 MeV, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 344(2015) 76–82.
 H. Naik, S. Singh, A. Goswami, V.K. Manchanda, G.N. Kim, K.S. Kim, M. W. Lee, Md. S. Rahman, D. Raj, S. Ganesan, S.V. Suryanarayana, M.H. Cho, W. Namkung, Measurement of photo-neutron cross-sections in 208Pb and 209Bi with 50–70 MeV bremsstrahlung, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 269 (2011) 1417-1424.
 W.B. Walters, J.P. Hummel, Studies of isomeric yield ratios in the production of Sc44, Mn52, and Y87 by photonuclear reactions, Physical Review 150 (1966) 867-876.
 M. Gholami, M. Kildir, A.N. Behkami, Microscopic study of spin cut-off factors of nuclear level densities, Physical Review C 75 (2007) 044308-044314.
 J.C. Krupa, Isomeric ratios for 134m,gCs and 135m,gCs produced by (p,3pxn) reactions on 139La from 40 to 150 MeV, Journal of Inorganic and Nuclear Chemistry 38 (1976) 965-968.
 D. Kolev, Studies of some isomeric yield ratios produced with bremsstrahlung, Applied Radiation and Isotopes 49 (1998) 989-995.
 D. Kolev, E. Dobreva, N. Nenov, V. Todorov, A convenient method for experimental determination of yields and isomeric ratios in photonuclear reactions measured by the activation technique, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 356 (1995) 390-396.
 T.D. Thiep, T.T. An, N.T. Khai, P.V. Cuong, N.T. Vinh, A.G. Belov, O.D. Maslov, Study of the isomeric ratios in photonuclear reactions of natural Selenium induced by bremsstrahlungs with end-point energies in the giant dipole resonance region, Journal of Radioanalytical and Nuclear Chemistry 292 (2012) 1035-1042.
 R. Vanska, R. Rieppo, The experimental isomeric cross-section ratio in the nuclear activation technique, Nuclear Instruments and Methods in Physics Research 179 (1981) 525-532.
 A.J. Koning, S. Hilaire, S. Goriely, TALYS 1.6, A nuclear reaction program, User manual, 2013, <http://www.talys.eu/download-talys/>.
 R.B. Firestone, C.M. Baglin, F.S.Y. Chu, Table of isotopes, 8th Edition, Update on CD-ROM, John Wiley, New York, (1998).
 CDFE, On-line nuclear reaction threshold and energy values calculator, <http://cdfe.sinp.msu.ru/>
 A.G. Belov, Yu.P. Gangrsky, A.P. Tonchev, N.P. Balabanov, Excitation of Isomeric States 1h-11/2 in (g,n) reactions, Physics of Atomic Nuclei 59 (1996) 553-560.
 N.A. Demekhina, A.S. Danagulyan, G.S. Karapetyan, Isomeric ratio analysis in (gamma,n) and (gamma,p) reactions at giant resonance energy range, Physics of Atomic Nuclei 65 (2002) 390-395.
 T.D. Thiep, T.T. An, N.T. Khai, N.T. Vinh, P.V. Cuong, A.G. Belov, O.D. Maslov, The isomeric ratios in some photonuclear reactions (gamma,n), (gamma,p), (gamma,2n), and (gamma,np) induced by bremsstrahlung with end-point energies in the giant dipole resonance region, Physics of Particles and Nuclei Letters 6 (2009) 126-133.
 M.G. Davydov, V.G. Magera, A.V. Trukhov, E. M. Shomurodov, Isomeric ratios of the photonuclear reactions yields for gamma-activation analysis, Soviet Atomic Energy 58 (1985) 56-59.
 Md. S. Rahman, M. Lee, K-S. Kim, G.N. Kim, E. Kim, M-H. Cho, V. Shvetshov, P.D. Khue, N. Van Do, Measurement of Isomeric-yield ratios of 109m,gPd and 115m,gCd with 50-, 60-, and 70-MeV bremsstrahlung, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 276 (2012) 44–50.