112105460
The DELPHI Microvertex Detector
The main characteristics of the DELPHI Microvertex Detector are presented. The performance in terms of impact parameter resolution, association efficiency, and ambiguity is evaluated after two years of data taking at LEP.
120429047
The design of the optical components and gas control systems of the CERN Omega ring imaging Cherenkov detector
Abstract A large ring imaging Cherenkov detector (RICH) has been commissioned for use at the CERN Omega spectrometer. In the first of a series of reports we begin by discussing the general design of the device and illustrate the dependence of the attainable spatial resolution and range of particle identification on its optical parameters. We then describe in detail the construction and performance of the major optical components and gas systems of the detector.
122563794
A new photomultiplier tube utilising channel plate electron multipliers as the gain producing elements
Abstract A survey of the properties of a new type of photomultiplier tube is presented. The device is a planar structure in which two cascaded channel plate electron multipliers (CPEM) produce charge gain factors of greater than 10 7 with a transit time of 1 ns. The single electron pulse rise time and transit time spread figures are 1 ns and 2.5 ns fwhm. The tube has shown its ability to operate satisfactorily in magnetic fields of 1 T without magnetic screening. Saturation of the tube occurs at a peak pulse current of 40 mA with plastic scintillator pulses. However the high plate impedances cause serious rate limitations with high output pulses.
122893386
Measurement of the spatial resolution of double-sided double-metal AC-coupled silicon microstrips detectors
Abstract The design and first results from double-sided silicon microstrip detectors designed for use in the DELPHI experiment at LEP are presented. The detectors are AC-coupled on both the n- and p-side. A novel readout scheme using a second metal layer has been implemented, allowing the readout of both coordinates on the same edge of the detector. The detectors have been tested in a high energy beam at the CERN SPS. Results on spatial resolution, pulse-height correlation and charge division are presented. The spatial resolution of the n-side has been measured as a function of the beam particle incident angle from 0 to 60°.
18645695
The recent operational performance of the CERN omega ring imaging cerenkov detector
We discuss the design and construction of the Time Projection chambers (TPCs) of the Omega Ring Imaging Cerenkov Detector (RICH). Details are given of the TPC high voltage system and its monitoring and control. In addition, the operation and monitoring of the readout is described together with results of tests on the performance of the front end amplifiers. The operation of the RICH TPCs and electronics during the first data run of WA69, in 1984, is discussed together with relevant results from laboratory tests. Results from the preliminary analysis of a sample of data from the 1984 run are also presented.
120457455
The DELPHI Microvertex detector
The DELPHI Microvertex detector, which has been in operation since the start of the 1990 LEP run, consists of three layers of silicon microstrip detectors at average radii of 6.3, 9.0 and 11.0 cm. The 73728 readout strips, oriented along the beam, have a total active area of 0.42 m2. The strip pitch is 25 μm and every other strip is read out by low power charge amplifiers, giving a signal to noise ratio of 15:1 for minimum ionizing particles. On-line zero suppression results in an average data size of 4 kbyte for Z0 events. After a mechanical survey and an alignment with tracks, the impact parameter uncertainty as determined from hadronic Z0 decays is well described by (69pt)2 + 242 μm, with pt in GeV/c. For the 45 GeV/c tracks from Z0 → μ− decays we find an uncertainty of 21 μm for the impact parameter, which corresponds to a precision of 8 μm per point. The stability during the run is monitored using light spots and capacitive probes. An analysis of tracks through sector overlaps provides an additional check of the stability. The same analysis also results in a value of 6 μm for the intrinsic precision of the detector.
107398289
THE FONT5 PROTOTYPE ILC INTRA-TRAIN FEEDBACK SYSTEM AT ATF2
We present the design and beam test results of a prototype beam-based digital feedback system for the Interaction Point of the International Linear Collider. A custom analogue front-end signal processor, FPGA-based digital signal processing boards, and kicker drive amplifier have been designed, built, deployed and tested with beam in the extraction line of the KEK Accelerator Test Facility (ATF2). The system was used to provide orbit correction to the train of bunches extracted from the ATF damping ring. The latency was measured to be approximately 140 ns.
59334407
DESIGN AND INITIAL RESULTS OF A TURN-BY-TURN BEAM POSITION MONITORING SYSTEM FOR MULTIPLE BUNCH OPERATION OF THE ATF DAMPING RING
An FPGA-based monitoring system has been developed to study multi-bunchbeam instabilities in the damping ring (DR) of the KEK Accelerator Test Facility (ATF), utilising a stripline beam position monitor(BPM) and existing BPM processor hardware. The system is designed to record the horizontal and/or vertical positions of up to three bunches in the DR in single-bunch multi-train mode or the head bunch of up to three trains in multi-bunch mode, with a bunch spacing of 5.6 ns. The FPGA firmware and data acquisition software were modified to record turn-by-turn data for up to six channels and 1‐3 bunches in the DR. An overview of the system and initial results will be presented.
59319996
DEVELOPMENT OF A TURN-BY-TURN BEAM POSITION MONITORING SYSTEM FOR MULTIPLE BUNCH OPERATION OF THE ATF DAMPING RING
An FPGA-based monitoring system has been developed to study multi-bunchbeam instabilities in the damping ring (DR) of the KEK Accelerator Test Facility (ATF). The system utilises a stripline beam position monitor (BPM) and single-stage down-mixing BPM processor. The system is designed to record the horizontal and/or vertical positions of up to three bunches in the DR with c. 150ns bunch spacing, or the head bunch of up to three trains in a multi-bunch mode with a bunch spacing of 5.6 ns. The FPGA firmware and data acquisition software allow the recording of turnby-turn data. An overview of the system and performance results will be presented.