The Species beamline, a soft x-ray beamline on the 1.5 GeV ring, received first light 1 April 2019 and since then the team have been busy commissioning and characterizing the performance of the beamline. In short, theory and reality align very well and the first APXPS experiment with synchrotron radiation at SPECIES has been demonstrated.
The image above shows the comparison of undulator spectrum, measured at 20 mm gap, between theory (black) and experiment (red). Calculated spectrum is normalised with beamline transmission and photodiode efficiency.
Beam profile measurement at 14 mm undulator gap at different harmonics. Measured at beam position monitor after exit slit while scanning monochromator baffles, which had been set to an opening of 0.3 x 0.3 mm. Preliminary flux estimations also agree quite well with calculated values.
The first APXPS results indicate also that the high brightness of the synchrotron light allows us to measure in the intended pressure ranges. The attached spectra are preliminary results from the ambient pressure cell, with a silver single crystal test sample and N2 gas at different pressures. Each Ag 3d spectrum took 75 seconds to measure. The results show that there is still a high signal at 10 mbar of gas pressure. These available pressure ranges are likely to be further increased, as the beamline performance is further characterized and upgraded.
The team will characterize the exact beam spot size in the endstation soon as well.
A lot of work still lies ahead of the Species team before they are ready to receive regular users and soon commissioning of the RIXS branch will begin. Moreover, the APXPS endstation still requires some further alignment and characterization of the synchrotron beam. However, the team is optimistic about this since the initial phases of the commissioning have gone according to the plan.