[en] The NIKHEF Travelling Wave Monitor (TWM) is a sensitive, non intercepting device to measure beam displacement. The measurement is independent of the beam intensity. The TWM consists of a waveguide assembly and separate electronics assembly. Specifications are given, as well as instructions for use. (Auth./G.J.P.)

[en] The electronics in the injector of the NIKHEF-K electron accelerator works at a voltage level of 400K volts. In order to control the pulsshape and the reliability of the pulser the measuring signal has to be brought down to ground-level. Therefore a measuring set-up has been developed based upon glassfibre which is described in this report. 9 figs

[en] The operating RF frequency of the AmPS stretcher ring is 2856 MHz. The beam pipe cross section is above cut-off for some modes of this frequency. This inhibits proper functioning of the stripline beam position monitors. The problem has been solved by applying particularly shaped high vacuum quality RF dampers

[en] For the 'electron gun' of the NIKHEF electron accelerator a High Voltage Pickup Plate (HVPP) has been constructed with belonging electronics, in order to iinvestigate the stability of the voltage of the electron gun. With the HVPP it is possible to measure the absolute quantities of the instabilities, as result of the rectifying and the pulsed load, of the ICT. (author). 28 figs.; 1 tab

[en] AmPS (Amsterdam Pulse Stretcher) is a 900 MeV electron storage and stretcher ring. Its construction started early 1991. A fast response, high resolution stripline type beam position monitor has been developed for the ring. The monitor has a quasi elliptic cross section. Its sensing strips have a length of λ/4; the operating frequency is 2,856 MHz. The mechanical construction, the matching of the output ports and the on-line calibration system are described. The results of bench measurements as well as measurements with a 500 MeV beam are also presented

No abstract available

[en] An overview of the polarized electron source used at the NIKHEF accelerator facility is given. Since its first operation in September 1996 we have obtained currents in the source larger than 150 mA, and polarization degrees up to 88%. Approximately 350 hours have been dedicated to physics with a polarized ³He internal target. Using one InGaAsP photocathode, 2 μs long pulses were produced with a current of 2 mA in the local linac, with a polarization degree of 82.5%, at a repetition rate of 1 Hz. Source operations had to be interrupted about every eleventh day for approximately an hour for photocathode reactivation. A photocathode lifetime (1/e) of 180 hours has been achieved

[en] The LHCb Outer Tracker straw tubes have shown to suffer from gain loss after irradiation in the laboratory at moderate intensities. Under irradiation an insulating layer is formed on the anode wire. The ageing is caused by contamination of the counting gas due to outgassing of the plastifier di-isopropyl-naphthalene in araldite AY103-1 used at construction. This paper presents irradiation results with and without the plastifier, together with the mass spectra of the glue samples. In addition, the effects of wire heating and large currents are presented.

[en] The LHCb experiment is a single-arm spectrometer, designed to study B-hadron decays at the Large Hadron Collider (LHC). It is crucial to accurately and efficiently track the charged decay products with the Outer Tracker straw tube detector, in the high-density particle environment of the LHC. The Outer Tracker Front End electronics provide the precise (0.5 ns) drift-time measurement, at an average occupancy of 5% and at a 1 MHz trigger rate. The tracking procedure requires high-efficiency, while at the same time putting stringent limits on the noise level. The mass production and installation of 450 fully operational Front End boxes is completed. Quality checks have been performed at several stages, at the level of individual boards and at the global level with dedicated test systems mimicking the real detector and capable of simulating all the readout functionalities. An excellent overall threshold uniformity is achieved with low noise levels.

[en] For the outer tracking system of the LHCb spectrometer 53.760 straws of 2.5m length will be used. They are arranged in detector modules of 5m length and 0.34m width. The envisaged spatial resolution over the entire active area is 200μm resulting in stringent requirements on the accuracy for the module construction.In this paper we discuss the optimisation of the straws, design and construction of detector modules. The long-term operation properties of straws in two different counting gases, Ar/CO2 (70/30) and Ar/CO2/CF4 (75/10/15), are compared