Implementation of the Munich scanning positron microscope at the positron source NEPOMUC
Zeitschrift:
Physica Status Solidi (C) Current Topics in Solid State Physics
Jahrgang:
4
Heftnummer:
10
Konferenztitel:
ICPA 14
Jahr:
2007
Seiten von - bis:
4028-4031
Sprache:
Englisch
Stichwörter:
Energy ranges ; International conferences ; Lateral resolutions ; Low-intensity ; Measurement times ; NEPOMUC ; Positron lifetime measurements ; Positron sources, Electrons ; Particle beams ; Positron annihilation ; Positron annihilation spectroscopy ; Scanning ; Security of data ; Self phase modulation ; Single point mooring ; Standards ; Statistical process control ; Superconducting materials, Positrons
Abstract:
The Munich scanning positron microscope (SPM) permits positron lifetime measurements with a lateral resolution down to 2 um within an energy range of 1-20 keV. One practical limitation of the SPM is set by the long measurement times of several days per a 2D-scan due to the low intensity positron beam produced by standard 22Na sources. This disadvantage will be overcome by installing the SPM at the high intense positron beam facility NEPOMUC at the research reactor FRM II in Garching. Thus the time for one measurement will be shortened by a factor of 60. In addition it is expected to reduce the lateral resolution to about 100 nm. Due to the beam characteristics of the NEPOMUC facility an interface is needed, which enhances the phase space density of the beam. The requirements, which have to be fulfilled by the interface, will be described and an overview of the different components such as bunching units, remoderation stages and rf-elevator will be given. «
The Munich scanning positron microscope (SPM) permits positron lifetime measurements with a lateral resolution down to 2 um within an energy range of 1-20 keV. One practical limitation of the SPM is set by the long measurement times of several days per a 2D-scan due to the low intensity positron beam produced by standard 22Na sources. This disadvantage will be overcome by installing the SPM at the high intense positron beam facility NEPOMUC at the research reactor FRM II in Garching. Thus the ti... »