核光子学
Nuclear Photonics
摘要：
与目前世界领先的HIGS设施（杜克大学，USA），具有10^8 g/s和Δ E_g/E_g~0.03。甚至g束的种子量子自由电子激光也可能成为可能，具有更高的亮度和光谱通量。与此同时，聚焦g束的新的令人兴奋的可能性也随之出现。我们描述了一个新的实验，在g-梁的ILL反应堆（格勒诺布尔），在那里我们观察到的第一次，g-梁的折射率是由虚拟对创建。使用折射和反射光学的组合，有效的单色器的g-光束正在开发中。因此，我们必须优化g束装置、g束流光学和g探测器的系统。我们可以用g-强度来交换带宽，将其降低到Δ E_g/E_g ~ 10^-6，并处理单个核能级。“核光子学”强调核应用的重要性。我们可以用g射线来处理单个的核同位素，而不仅仅是像X射线那样的元素。与X射线相比，g射线可以更深入地穿透大型样品，如放射性废物桶，发动机或电池。我们可以通过使用Nucl. Reson聚焦到微米分辨率来进行断层扫描和显微镜研究。具有eV分辨率和高空间分辨率的荧光检测。在新的应用背景下，我们讨论了M1和E1激发的主要形式，如剪刀模、双声子四极八极激发、侏儒偶极激发和巨偶极激发。我们在生物医学、绿色能源、放射性废物管理或国土安全方面发现了许多新的应用。此外，还可以产生更明亮的中子和正电子次级束。
英文摘要：
With new gamma-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest with 10^13 g/s and a bandwidth of Delta E_g/E_g ~10^-3, a new era of g-beams with energies <=20 MeV comes into operation, compared to the present world-leading HIGS facility (Duke Univ., USA) with 10^8 g/s and Delta E_g/E_g~0.03. Even a seeded quantum FEL for g-beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused g-beams. We describe a new experiment at the g-beam of the ILL reactor (Grenoble), where we observed for the first time that the index of refraction for g-beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for g-beams are being developed. Thus we have to optimize the system of the g-beam facility, the g-beam optics and g-detectors. We can trade g-intensity for band width, going down to Delta E_g/E_g ~ 10^-6 and address individual nuclear levels. 'Nuclear photonics' stresses the importance of nuclear applications. We can address with g-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, g-beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to micron resolution using Nucl. Reson. Fluorescence for detection with eV resolution and high spatial resolution. We discuss the dominating M1 and E1 excitations like scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of applications. We find many new applications in biomedicine, green energy, radioactive waste management or homeland security. Also more brilliant secondary beams of neutrons and positrons can be produced.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
