Improvements on the third generation of electron momentum spectrometer

The significant modifications to our recently constructed electronmomentum spectrometer have been implemented. Compared with ourprevious report, the energy and the angle resolutions aresignificantly improved and reach ΔE=0.45eV, Δθ=±0.53^o and Δπ=±0.84^o,respectively. Moreover, the details of data reduction and therelation between azimuthal angle range and the sensitivity arediscussed.