Ortho-positronium re-emission yield and energy in surfactant-templated mesoporous silica films

摘要：

Measurement of the ortho-positronium (o-Ps) re-emission yield from thin mesoporous silica films into vacuum gives information on the porosity and pore interconnection. In addition, the emitted o-Ps can be used as a target for antiprotons to produce antihydrogen as well as in other experiments which require a high density of o-Ps in vacuum. We studied the re-emission yield from thin surfactant-templated mesoporous silica films deposited on glass. The measurements were performed in reflection mode with a specially designed lifetime spectrometer mounted on a slow positron beam system at CERN. The intensity of the 142 ns vacuum lifetime component was recorded as a function of the energy of the positron beam. Values as high as 40％ were found for the re-emission efficiency at low positron energy.

作者: L.Liszkay A.Rubbia M.Etienne A.Walcarius C.Corbel P Perez P.Desgardin M.-F.Barthe T.Ohdaira R.Suzuki P.Crivelli U.Gendotti

作者单位: DSM/IRFU,CEA Saclay F-91191 Gif-sur-Yvette Cedex,France Institut für Teilchenphysik,ETHZ,CH-8093 Zürich,Switzerland LCPME,CNRS-Nancy-Université,405 rue de Vandoeuvre,F-54600 Villers-lès-Nancy,France DSM/ IRAMIS,CEA Saclay F-91191 Gif-sur-Yvette Cedex,France CNRS-CERI,3A rue de la Férollerie,F-45071 Orléans Cedex 2,France National Institute of Advanced Industrial Science and Technology (AIST),Tsukuba,Ibaraki 305-8568,Jap

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: 9

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）