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Register a new userWhat can we know about hypernuclei via analysis of bremsstrahlung photons?
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We investigate possibility of emission of the bremsstrahlung photons in nuclear reactions with hypernuclei for the first time. A new model of the bremsstrahlung emission which accompanies interactions between $alpha$ particles and hypernuclei is constructed, where a new formalism for the magnetic momenta of nucleons and hyperon inside hypernucleus is added. For first calculations, we choose $alpha$ decay of the normal nucleus $^{210}{rm Po}$ and the hypernucleus $^{211}_{Lambda}{rm Po}$. We find that (1) emission for the hypernucleus $^{211}_{Lambda}{rm Po}$ is larger than for normal nucleus $^{210}{rm Po}$, (2) difference between these spectra is small. We propose a way how to find hypernuclei, where role of hyperon is the most essential in emission of bremsstrahlung photons during $alpha$ decay. As demonstration of such a property, we show that the spectra for the hypernuclei $^{107}_{Lambda}{rm Te}$ and $^{109}_{Lambda}{rm Te}$ are essentially larger than the spectra for the normal nuclei $^{106}{rm Te}$ and $^{108}{rm Te}$. Such a difference is explained by additional contribution of emission to the full bremsstrahlung, which is formed by magnetic moment of hyperon inside hypernucleus. The bremsstrahlung emission formed by such a mechanism, is of the magnetic type. A new formula for fast estimations of bremsstrahlung spectra for even-even hypernuclei is proposed, where role of magnetic moment of hyperon of hypernucleus in formation of the bremsstrahlung emission is shown explicitly. Such an analysis opens possibility of new experimental study of properties of hypernuclei via bremsstrahlung study.
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We investigate emission of bremsstrahlung photons during scattering of $alpha$-particles off nuclei. For that, we construct bremsstrahlung model for $alpha$-nucleus scattering, where a new formalism for coherent and incoherent bremsstrahlung emissions in elastic scattering and mechanisms in inelastic scattering is added. Basing of this approach, we analyze experimental bremsstrahlung cross-sections in the scattering of $alpha$-particles off the isotope[59]{Co}, isotope[116]{Sn}, isotope[rm nat]{Ag} and isotope[197]{Au} nuclei at 50 MeV of $alpha$-particles beam measured at the Variable Energy Cyclotron Centre, Calcutta. We observe oscillations in the calculated spectra for elastic scattering for each nucleus. But, for isotope[59]{Co}, isotope[116]{Sn} and isotope[rm nat]{Ag} we obtain good agreement between calculated coherent spectrum with incoherent contribution for elastic scattering with experimental data in the full photon energy region. For heavy nucleus isotope[197]{Au} we find that (1) Oscillating behavior of the calculated spectrum of coherent emission in elastic scattering is in disagreement with experimental data, (2) Inclusion of incoherent emission improves description of the data, but summarized spectrum is in satisfactory agreement with the experimental data. To understand unknown modification of wave function for scattering, we add new mechanisms of inelastic scattering to calculations and extract information about unknown new amplitude of such mechanisms from experimental data analysis. This amplitude has maxima at some energies, that characterizes existence of states of the most compact structures (clusters) in nucleus-target. We explain origin of oscillations in the bremsstrahlung spectra for elastic scattering (at first time). New information about coherent and incoherent contributions is extracted for studied reactions.
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