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arXiv · 1304.5358

First measurements with the Munich 2D-ACAR spectrometer on Cr

Hubert Ceeh·Josef Andreas Weber·Michael Leitner·Peter Böni·Christoph Hugenschmidt
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Abstract

The Munich 2D-ACAR spectrometer at the Maier-Leibnitz accelerator laboratory in Garching has recently become operational. In the present implementation a 2D-ACAR spectrometer is set up, with a baseline of 16.5m, a conventional 22Na positron source and two Anger-type gamma-cameras. The positrons are guided onto the sample by a magnetic field generated by a normal conducting electromagnet. The sample can be either cooled by a standard closed-cycle-cryostat to low temperatures or heated by a resistive filament to temperatures up to 500K. We present the key features of this new 2D-ACAR spectrometer and, in addition, discuss first measurements on the pure metal system Cr. The 2D-ACAR measurements have been performed on Cr at different temperatures: at 5K and at room temperature in the anti-ferromagnetic phase and at 318K slightly above the paramagnetic phase transition.

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Hubert Ceeh, Josef Andreas Weber, Michael Leitner, Peter Böni, Christoph Hugenschmidt. 2013-04-19. First measurements with the Munich 2D-ACAR spectrometer on Cr. https://doi.org/10.1088/1742-6596/443/1/012094

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