May 3rd, 2016

лошадь, диаграмма, Фейнман

Квантовый хаос в ядрах

Статья с крутым названием:
First clear evidence of quantum chaos in the bound states of an atomic nucleus: http://arxiv.org/abs/1605.00210

We study the spectral fluctuations of the 208Pb nucleus using the complete experimental spectrum of 151 states up to excitation energies of 6.20 MeV recently identified at the Maier-Leibnitz-Laboratorium at Garching, Germany. For natural parity states the results are very close to the predictions of Random Matrix Theory (RMT) for the nearest-neighbor spacing distribution. A quantitative estimate of the agreement is given by the Brody parameter ω, which takes the value ω=0 for regular systems and ω≃1 for chaotic systems. We obtain ω=0.85±0.02 which is, to our knowledge, the closest value to chaos ever observed in experimental bound states of nuclei. By contrast, the results for unnatural parity states are far from RMT behavior. We interpret these results as a consequence of the strength of the residual interaction in
208Pb, which, according to experimental data, is much stronger for natural than for unnatural parity states. In addition our results show that chaotic and non-chaotic nuclear states coexist in the same energy region of the spectrum.

Примечательно, что они строят распределения на гораздо меньшей статистике, чем у нас.
лошадь, диаграмма, Фейнман

Новая статья Бессонова - красивый проект рентгеновского источника

Design study of compact Laser-Electron X-ray Generator for material and life science applications: http://arxiv.org/abs/1604.08839

Вдогонку - их же статья: To the Thomson cross-section of light scattered by moving particle: http://arxiv.org/abs/1605.01433

In this paper in a framework of classical electrodynamics, we re-derived in a simple way the formula for the light scattering by moving particle with arbitrary angle of collision.