Nuclear resonant X-ray optics by the use of synchrotron radiation

利用超强同步辐射对核共振散射进行了研究。这些研究的主要成果如下。(1)研制了一种由四个硅单晶组成的新型单色仪，获得了带宽为几兆电子伏安的X射线束。此外，还设计并制作了一台可变能量核单色仪，在衍射条件下，通过单色仪的多普勒运动扫描反射光束的能量。(2)在1mus以上的时间范围内，观察到了~(57)Gt；Fe_2O_3的核Bragg散射的时间谱。利用衰变曲线中的量子拍频，确定了^&lt；57&gt；Fe的超精细结构参数。(3)观察到了锡-β锡箔的相干核前向散射的时间谱。在衰变时间接近1…的情况下，还观察到了高散射角下非相干核共振散射的时间谱。更多的y等于孤立的原子核。(4)获得了^&lt；169&gt；TmFeO_3晶体的核前向散射。(5)用核共振散射作为探测束，分析了压电振荡硅晶体的X射线非弹性散射。(6)用X射线频闪形貌术直接观测了射频磁场作用下FeBO_3晶体中的磁弹性波。(7)在外加磁场作用下，利用达亚蒙德顶压室对SrFeO_3的压致相变进行了时间域穆斯堡尔谱研究。(8)干涉计量学研究是通过在干涉仪的路径上插入一个多普勒振荡的核散射体来进行的。(9)利用长相干长度的核散射束实现了不同光路的X射线干涉仪。(10)首次在液体中观察到了^&lt；57&gt；Fe核激发。在这里，由于反冲造成的能量损失被同步辐射的宽带所补偿。(11)用铁-铁箔首次观测到伴随声子激子的核共振散射。较少

Studies on nuclear resonant scattering by the use of ultra-intense synchrotron ragiation were carried out. Main achievements of these studies are as follows. (1) A New type of monochromator composed of separated four silicon crystals was completed from which an X-ray beam with a band width of a few meV was obtained. In addition a variable energynuclear monochromator was designed and constructed in which the energy of the reflected beam could be scanned by a Doppler motion of the monochromator under the diffraction condition. (2) A time spectrum of nuclear Bragg scattering from ^<57>Fe_2O_3 was observed in a time range extending over 1mus. Using the quantum beat in the decay curve the values of the hyperfine structure parameters of ^<57>Fe were determined. (3) A time spectrum of coherent nuclear forward scattering from a ^<119>Sn-beta tin foil was observed. A time spectum of incoherernt nuclear resonant scattering at a high scattering angle was also observed where a decay time was nearl … More y equal to that of an isolated nucleus. (4) Nuclear forward scattering of ^<169>Tm from a ^<169>TmFeO_3 crystal were obtained. (5) X-ray inelastic scatterin from a silicon crystal oscillated piezo-electrically was analyzed by using the nuclear resonant scattering as a probe beam. (6) X-ray stroboscopic topography was used for the direct observation of magneto-elastic waves in a FeBO_3 crystal to which a RF magnetic field was applied. (7) Time domain Mossbauer spectroscopic studies of pressure-induced transition in SrFeO_3 were performed using a daiamond anvil cell under an external magnetic field. (8) Interferometric studies were made by inserting a Doppler-oscillated nuclear scatterer to a path of an interferometer. (9) An X-ray interferometer with different optical paths was realized by the use of the nuclear scattered beam having a long coherence length. (10) Nuclear excitation of ^<57>Fe nuclei in a liquid was observed for the first time. Here the energy loss due to recoil was compensated by the broad band of synchrotron radiation. (11) Nuclear resonant scattering accompanied by phonon excitaion was observed for the first time by using an ^<57>Fe-iron foil. Less