Els Koffeman

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This paper describes the AC-coupled, single-sided, pin -n silicon microstrip sensors used in the Semiconductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The(More)
This paper describes the silicon microstrip modules in the barrel section of the SemiConductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The module requirements, components and assembly techniques are given, as well as first results of the module performance on the fully assembled barrels that make up the detector being(More)
The ABCD3TA is a 128-channel ASIC with binary architecture for the readout of silicon strip particle detectors in the Semiconductor Tracker of the ATLAS experiment at the Large Hadron Collider (LHC). The chip comprises fast front-end and amplitude discriminator circuits using bipolar devices, a binary pipeline for first level trigger latency, a second level(More)
The challenges for the tracking detector systems at the LHC are unprecedented in terms of the number of channels, the required read-out speed and the expected radiation levels. The ATLAS Semiconductor Tracker (SCT) end-caps have a total of about 3 million electronics channels each reading out every 25 ns into its own on-chip 3:3 ms buffer. The highest(More)
Measurements of the cross sections for charged current deep inelastic scattering in e + p collisions with a longitudinally polarised positron beam are presented. The measurements are based on a data sample with an integrated luminosity of 132 pb −1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is(More)
The photoproduction of prompt photons, together with an accompanying jet, has been studied in ep collisions at a centre-of-mass energy of 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 77 pb −1. Cross sections were measured for the transverse energy of the photon and the jet larger than 5 and 6 GeV, respectively. The differential(More)
To fully exploit the HERA-II upgrade, the ZEUS experiment has installed a Mi-cro Vertex Detector (MVD) using n-type, single-sided, silicon µ-strip sensors with capacitive charge division. The sensors have a readout pitch of 120 µm, with five intermediate strips (20 µm strip pitch). The designs of the silicon sensors and of the test structures used to verify(More)
The ZEUS detector has been used to study dissociation of virtual photons in events with a leading proton, γ ⋆ p → Xp, in e + p collisions at HERA. The data cover photon virtualities in two ranges, 0.03 < Q 2 < 0.60 GeV 2 and 2 < Q 2 < 100 GeV 2 , with M X > 1.5 GeV, where M X is the mass of the hadronic final state, X. Events were required to have a leading(More)
The development of a proton radiography system to improve the imaging of patients in proton beam therapy is described. The system comprises gridpix based time projection chambers, which are based on the Timepix chip designed by the Medipix collaboration, for tracking the protons. This type of detector was chosen to have minimal impact on the actual(More)