The measurement of photocathode transverse energy distribution curves (TEDCs) using the transverse energy spread spectrometer (TESS) experimental system.

The minimum achievable particle beam emittance in an electron accelerator depends strongly on the intrinsic emittance of the photocathode electron source. This is measurable as the mean longitudinal and transverse energy spreads in the photoemitted electron beam (MLE and MTE respectively); consequently, MLE and MTE are notable figures of merit for photocathodes used as electron sources in particle accelerators. The overall energy spread is defined by the sum of the MTE and the MLE, and the minimization of MTE is crucial to reduce emittance and thus generate a high-brightness electron beam.

Spectroscopy of systems with time variable parameters: photoreflectance of GaAs(001) under cesium adsorption.

A modification of photoreflectance spectroscopy, which improves the precision and efficiency of measuring time-evolving surface electric fields, is proposed. This modification is explored for studying the band bending evolution under cesium adsorption on the reconstructed GaAs(001) surface and relaxation processes in the non-equilibrium adsorbate overlayer. Observation of several distinct maxima and minima in the coverage dependence of the band bending can be explained by the formation of adatom-induced surface states with a quasi-discrete spectrum.

Al, Zn, Cu, Mn and Fe levels in brain in Alzheimer's disease.

The aim of our experiments was to investigate the possible element concentration changes in Alzheimer's disease. Our project incorporated the determination of the regional distribution of elements in normal human brain, too. Five elements (Al, Zn, Cu, Mn and Fe) have been measured in 10 different regions of 20 normal brains (mean age 70 years) and in brain parts of patients with Alzheimer's disease (9 individuals).

Follow-up studies of visual potentials in multiple sclerosis evoked by checkerboard and foveal stimulation.

Visual cortical potentials were evoked by reversal of a checkerboard pattern and a small quadrangular foveal stimulus. Examination of 68 patients with MS showed the highest detection rate for abnormality of VEPs with a combination of both methods. Follow-up studies revealed changes (improvement or impairment) of VEP amplitudes or latencies in nearly half of the patients.