Columbia University microbeam was constructed in 1993 and finished by the end of 1995. It is well established and used routinely to irradiate cells in a highly localized spatial region with a defined number of α-part...Columbia University microbeam was constructed in 1993 and finished by the end of 1995. It is well established and used routinely to irradiate cells in a highly localized spatial region with a defined number of α-particles. By using this probe, it is possible to study a number of radiobiological questions in ways that cannot be simulated by using conventional broad-field exposures. This report describes the development and current capabilities of the Columbia University microbeam, as well as the preliminary researches undertaken.展开更多
The developed track detector consists of two parts: a small drift region to obtain a good tracking and a relatively large multiplication region for getting an enough high gain at low pressure. All the track detector c...The developed track detector consists of two parts: a small drift region to obtain a good tracking and a relatively large multiplication region for getting an enough high gain at low pressure. All the track detector can be moved in the direction perpendicular to the beam by means of a micrometric screw. An automatic system allows the counting gas to flow continuously at constant pressure through the detector during the measurements. The system can measure ionization distributions at a few nanometer range.展开更多
文摘Columbia University microbeam was constructed in 1993 and finished by the end of 1995. It is well established and used routinely to irradiate cells in a highly localized spatial region with a defined number of α-particles. By using this probe, it is possible to study a number of radiobiological questions in ways that cannot be simulated by using conventional broad-field exposures. This report describes the development and current capabilities of the Columbia University microbeam, as well as the preliminary researches undertaken.
文摘The developed track detector consists of two parts: a small drift region to obtain a good tracking and a relatively large multiplication region for getting an enough high gain at low pressure. All the track detector can be moved in the direction perpendicular to the beam by means of a micrometric screw. An automatic system allows the counting gas to flow continuously at constant pressure through the detector during the measurements. The system can measure ionization distributions at a few nanometer range.