Design and Development of the Irradiation Chamber for Radiobiological Experiments Using Synchrotron Radiation in the Energy Region 0.4 - 5 keV.

国家高能物理实验室光子工厂的同步辐射是第一个致力于包括辐射生物学在内的各种项目实验的主要设施。在0.4-5keV能量范围内的同步辐射软X射线有望成为辐射生物学中最重要的工具之一，因为单色软X射线可以作为细胞内生物敏感结构的精细探针。然而，软X射线不能用于常规的放射生物学实验，因为大部分辐射能量被空气相吸收。在本研究中，我们设计并研制了使用软X射线的照射室，使我们能够在真空或氦气相中用X射线照射培养的细胞。可以在垂直于X射线束的平面上对辐照样品和整个腔体进行二维扫描，以扩大照射面积并平均强度分布。在束线的辐照腔和单色计之间安装了差动泵浦系统。辐照实验的操作可由个人计算机系统自动控制。

The synchrotron radiation at the photon Factory, National Laboratory for High Energy Physics, is the first major facility dedicated to all kinds of project experiments including radiation biology. The soft X-rays within synchrotron radiation in the energy region 0.4-5 KeV is expected to be one of the most important tools in radiation biology, because the monochromatic soft X-rays can be used as a fine probe of the biologically sensitive structure within cells. However, the soft X-rays can not be used in the conventional radiobiological experiments because most of the radiation energy is absorbed by the air phase.In the present study, we designed and developed the irradiation chamber using such soft X-rays, which enabled us to irradiate the cultured cells with the X-rays in the vacuum or in the helium gas phase. The irradiation samples, together with the whole chamber, can be scanned two dimensionally in the plane vertical to the X-ray beam, to widen the irradiation area as well as to average the intensity distribution. The differential pumping system was installed between the irradiation chamber and the monochrometer in the beam line. Operation of the irradiation experiment can be automatically controlled by a personal computer system.