A brief description is given of the design principles and layout of the Dutch±Belgian beamline at the ESRF. This beamline optimizes the use of the available bending-magnet radiation fan by splitting the beam into two branches, each accommodating two experimental techniques.

We describe the realization of a phase-sensitive and ultrafast near-field microscope, optimized for investigation of surface plasmon polariton propagation. The apparatus consists of a homebuilt near-field microscope that is incorporated in Mach-Zehnder-type interferometer which enables heterodyne detection. We show that this microscope is able to measure dynamical properties of both photonic and plasmonic systems with phase sensitivity.

A novel set-up for Fourier transform ion cyclotron resonance mass spectrometry (FTICR) is reported for simultaneous infrared multiphoton dissociation (IRMPD) and electron-capture dissociation (ECD). An unmodified electron gun ensures complete, on-axis overlap between the electron and the photon beams. The instrumentation, design and implementation of this novel approach are described. In this configuration the IR beam is directed into the ICR cell using a pneumatically actuated mirror inserted into the ion-optical path. Concept validation was made using different combinations of IRMPD and ECD irradiation events on two standard peptides. The ability to perform efficient IRMPD, ECD and especially simultaneous IRMPD and ECD using lower irradiation times is demonstrated. The increase in primary sequence coverage, with the combined IRMPD and ECD set-up, also increases the confidence in peptide and protein assignments. Proteomics is an indispensable technology in the molecular description of life's organization. As proteins carry out most biological activities in a cell or organism, 1 it is essential to characterize their structure, expression, distribution and interactions. Over the past decade mass spectrometry (MS) has become the method of choice for the systematic analysis of a proteome. It has enabled protein identification and quantification, protein profiling, and the characterization of protein interactions and modifications. Nevertheless, MSbased proteomics still faces significant challenges, 1,2 such as the improvement of tandem mass (MS/MS) spectra in order to decrease the amount of false positives in peptide and protein assignments. Here we describe an instrumental development to improve the quality and information content of MS/MS spectra. A common method of protein identification uses partial sequence information of one or more proteolytic peptides. 1,3,4 This sequence-tag strategy involves proteolysis of the protein mixture, followed by chromatographic separation of peptides and MS/MS. The peak lists from such MS/ MS spectra are then submitted to a database for protein identification.The confidence of the assignment increases with the amount of sequence information and the mass accuracy of the measurement. The high mass accuracy provided by Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) is the principal reason for it currently being the method of choice for proteomics investigations. 4 With suitable control, FTICRMS can provide mass accuracies consistently under 2 ppm, and the majority under 1 ppm. 5-7

One of the limiting factors in the determination of the electroweak parameters from cross section measurements of e + e annihilation close to the Z pole is the precision of the luminosity measurement. The luminosity monitor of the L3 detector at LEP and the analysis of its data are described. Using a combination of a BGO calorimeter and a 3-layer silicon tracker, the absolute luminosity has been measured with an experimental precision of 0.08% in 1993 and 0.05% in 1994. The measurement relies on a detailed understanding of small-angle elastic e + e (Bhabha) scattering from the experimental and theoretical point of view, as well as an excellent knowledge of the detector geometry.

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