We show that the predictions of spatially smeared particle detectors coupled to quantum fields are not generally covariant outside pointlike limit. This lack covariance manifests itself as an ambiguity in time-ordering operation. analyze how breakdown affects typical detector models field theory such Unruh-DeWitt model. Specifically, we violations depend on state detectors-field system, shape a...

Several different vertex detector designs for the Linear Collider Detector (LCD) are evaluated in the context of measurements of the branching ratio of the standard model Higgs particle decaying into charm/anti-charm final states. Fast Monte Carlo simulations are used to model the detector and neural network-optimized flavor tagging is used to perform the measurements. These tools are used to s...

An excellent particle identification (PID) of hadrons and leptons over a large range of solid angle and momenta is an essential requirement for the precision measurement aims in PANDA experiment at FAIR, GSI [1]. For charged hadron identification in the barrel region of the PANDA detector, a compact imaging Cherenkov detector following the DIRC (Detection of Internally Reflected Cherenkov light...

In this paper it is explicitly demonstrated that the energy conservation law is kept when a detector uniformly accelerated in the Minkowski vacuum is excited and emits a particle. This fact had been hidden in conventional approaches in which detectors were considered to be forced on trajectories. To lift the veil we suggest the transition amplitude written in terms of the Minkowski coordinates....

Detecting the passage of an interfering particle through one of the interferometer's arms, known as "which path" measurement, gives rise to interference visibility degradation (dephasing). Here, we consider a detector at equilibrium. At finite temperature, dephasing is caused by thermal fluctuations of the detector. More interestingly, in the zero-temperature limit, equilibrium quantum fluctuat...

A fibre detector with multianode PM readout for high rate applications was developed for the HERA-B spectometer to cover the area near the beampipe. Such a detector has to operate at particle rates up to 2 ⋆ 10 mms and has to tolerate a radiation dosis up to 1 Mrad/y. The light output of test detectors with different scintillating fibres was measured as well as the light transport through clear...