Ortho-positronium quenching in low saturation-vapor-pressure gases

摘要：

The ortho-positronium pick-off annihilation rates in gaseous chloromethane (CH3Cl) and bromomethane (CH3Br) were measured at several pressures up to 1.2 atms using silica aerogel to form positronium. The saturation vapor pressures of these gasses at room temperature are low, 6 atms for CH3Cl and 1.9 atms for CH3Br. A half of the positrons emitted from 22Na into silica aerogel forms positronium independent of the gas pressure. We determined 1Zeff, the normalized ortho-positronium pick-off annihilation rate, for these gasses.

作者: K.Wada F.Saito T.Hyodo

作者单位: Komaba Organization for Educational Development,College of Arts and Sciences,The University fo Tokyo Institute of Physics,Graduate School of Arts and Sciences,University of Tokyo,3-8-1 Komaba,Meguro-ku Komaba Organization for Educational Development,College of Arts and Sciences,The University fo Tokyo

会议类型: 国际会议

会议名称: 第九届国际正电子与正电子素国际会议(9th International Workshop on Positron and Positronium Chemistry)(PPC–9)

会议地点: 武汉

会议语种:英文

页码: 27

在线出版日期: 2008-05-11（万方平台首次上网日期，不代表论文的发表时间）