INVESTIGATION OF (γ,n) REACTIONS IN THE CHANNEL OF MULTIPARTICLE PHOTODISINTEGRATION OF ¹²C AND ¹⁶O NUCLEI
Keywords:
diffusion chamber, photodisintegration, excitation energy, ground state of the 8Be nucleus
Abstract
The reactions 12С(γ,n)3Не2a and 16O(γ,n)3He3a is investigated by a method that employs a diffusion chamber placed in a magnetic field and irradiated by a beam of bremsstrahlung photons with an end-point energy of 150 MeV. In the excitation curve for the 2a system, a resonance is found, and this resonance identified as the ground state of the 8Be nucleus. The parameters of the γ-quantum and neutron are calculated, and the partial channels 12С(γ,n)3Не8Ве0 and 16O(γ,n)3Hea8Ве0 reactions are singled out. It is shown that these reactions proceed according a sequential-type scheme with the formation of one or several unresolved excited states of 11C and 15O nuclei at the first step. The total cross section of the reactions was determined and a similarity in their behavior was found for Eγ > 55 MeV. A jumplike change in the dependence of the kinetic energy of the neutron on Eγ in different energy intervals of the γ-quantum was observed.
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References
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5. Arkatov Yu.M., Vatset P.I., Voloshchuk V.I., et al. Photodisintegration of 4He nucleus down to threshold of meson production // Ukrainskij Fizicheskij Zhurnal. – 1978. – Vol. 23. – P. 1818-1840 (in Russian).
6. Kirichenko V.V., Khodyachikh A.F., Vatset P.I., et al. Study of reactions 12С(γ,p)7Li and 12С(γ,n)7Be at Eγmax = 120 MeV // Yad. Fiz. – 1979. – Vol. 29. – P. 572-581 (in Russian).
7. Afanas’ev S.N., Gorbenko E.S., Khodyachikh A.F. Investigation of the reaction mechanism for the four-particle photodisintegration of a carbon nucleus // Yad. Fiz. – 2007. – Vol. 70. – P. 873-881 (in Russian).
8. Khodyachikh A.F. Photonuclear reactions on p-shell nuclei at intermediate energies // PAST. Series: Nucl. Phys. Invest. – 2003. – Vol. 2. – P. 45-49 (in Russian).
9. Ayzatskiy N.I., Afanas’ev S.N., Buki A.Yu., et al. Investigation of atomic nuclei by electrons and protons with energies up to 300 MeV. – Kharkiv: Mis’kdruk, 2017. – 388 p. (in Russian).
10. Afanas’ev S.N., Khodyachikh A.F. On the mechanism of formation of excited states of the 8Be nucleus in the reaction 12C(,3) // Yad. Fiz. – 2008. – Vol. 71. – P. 1859-1869 (in Russian).
11. Afanas’ev S.N. The 8Be ground state formation in 16O(,4) reaction // The Journal of Kharkiv National University. Physical Series: «Nuclei, Particles, Fields». – 2012. – Vol. 1025. – P. 4-9 (in Russian).
12. Alcorta M., Borge M.J.G., Cubero M., et al. Properties of 12C resonances determined from the 10B(3He,pααα) and 11B(3He,dααα) reactions studied in complete kinematics // Phys. Rev. – 2012. – Vol. C86. – 064306 [6 pages].
13. Curtis N., Almaraz-Calderon S., Aprahamian A., et al. 8Be+8Be and 12C+α breakup states in 16O populated via the 13C(4He,4α)n reaction // Phys. Rev. – 2016. – Vol. C94. – 034313 [10 pages].
14. Baldin A.M., Gol’danski V.I., Maksimenko V.M., Rozental’ I.L. Kinematics of Nuclear Reactions. – Moscow: Atomizdat, 1968. – 456 p. (in Russian).
15. Tilley D.R., Kelley J.H., Godwin J.L., et al. Energy levels of light nuclei A = 8, 9, 10 // Nucl. Phys. – 2004. – Vol. A745. – P. 155-362.
16. Kelley J.H., Kwan E., Purcell J.E., et al. Energy levels of light nuclei A=11 // Nucl. Phys. – 2012. – Vol. A880. P. 88-195.
17. Ajzenberg-Selove F. Energy levels of light nuclei A =13-15 // Nucl. Phys. – 1991. – Vol. A523. – P. 1-196.
18. Balashov V.V., Fetisov V.N. Role of nucleon clusters in deep photo-disintegration of light nuclei // Nucl. Phys. – 1961. – Vol. 27. – P. 337-343.
19. Mamasahlisov V.M., Dzibuti R.I. High energy photodesintegration of 9Be and 12C nuclei // JETF. – 1961. – Vol. 41. – P. 1493-1497 (in Russian).
20. Maikov V.N. Some photoreactions on light nuclei // JETP. – 1958. – Vol. 6. – P. 973-982 (in Russian).
Published
2017-10-20
Cited
How to Cite
Afanas’ev, S. N. (2017). INVESTIGATION OF (γ,n) REACTIONS IN THE CHANNEL OF MULTIPARTICLE PHOTODISINTEGRATION OF ¹²C AND ¹⁶O NUCLEI. East European Journal of Physics, 4(3), 31-35. https://doi.org/10.26565/2312-4334-2017-3-04
Section
Original Papers
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