Synchrotron radiation time structure is becoming a common tool for studying dynamic properties of materials. The main limitation is often the wide time domain the user would like to access with pump-probe experiments. In order to perform photoelectron spectroscopy experiments over time scales from milliseconds to picoseconds it is mandatory to measure the time at which each measured photoelectron was created. For this reason the usual CCD camera-based two-dimensional detection of electron energy analyzers has been replaced by a new delay-line detector adapted to the time structure of the SOLEIL synchrotron radiation source. The new two-dimensional delay-line detector has a time resolution of 5 ns and was installed on a Scienta SES 2002 electron energy analyzer. The first application has been to characterize the time of flight of the photoemitted electrons as a function of their kinetic energy and the selected pass energy. By repeating the experiment as a function of the available pass energy and of the kinetic energy, a complete characterization of the analyzer behaviour in the time domain has been obtained. Even for kinetic energies as low as 10 eV at 2 eV pass energy, the time spread of the detected electrons is lower than 140 ns. These results and the time structure of the SOLEIL filling modes assure the possibility of performing pump-probe photoelectron spectroscopy experiments with the time resolution given by the SOLEIL pulse width, the best performance of the beamline and of the experimental station.

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The instrument VOLPE (volume photoemission from solids) is an experimental setup dedicated to high energy photoemission (PE) experiments. The instrument is equipped with an electrostatic hemispherical spectrometer especially designed to analyze high energy electrons (up to 10 keV) with high resolving power. In order to attain an energy resolution of a few tens of millielectron volts, we designed and constructed a dedicated input lens system, high stability power supplies, and a low dark-count detector and readout electronics. The system has been tested and is now operational on the ID16 beamline at European Synchrotron Radiation Facility, where an optical layout has been developed to perform high energy, high resolution PE experiments. First results show an overall energy resolution (electron + photon) of 71+/-7 meV at 5934 eV. The effective attenuation length of the photoelectrons is estimated to be 5+/-0.5 nm at a kinetic energy of 5 keV

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