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The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016–2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described. The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016-2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described.

The EXPADES (EXotic PArticle DEtection System) detector array consists of 16 Double Side Silicon Strip Detectors (DSSSD) with active areas of 64 × 64 mm 2 , arranged in 8 ΔE (40/50 μm)–E (300 μm) telescopes. All detector faces are segmented into 32 × 2-mm wide strips, ensuring a 2 × 2 mm 2 pixel configuration. Eight ionization chambers can be alternatively used as ΔE stages or, if needed, as an additional third layer for more complex triple telescopes. The signals from silicon ΔE layers and from ionization chambers are read by standard electronics, while innovative 32-channel ASIC chips are employed for the readout of the E stages. The results of off-line tests with alpha sources and from the first in-beam experiment with a 17 O beam are presented.

We describe the experimental set-up of the Radioactive Ion Beam (RIB) in-flight facility EXOTIC consisting of: (a) two position-sensitive Parallel Plate Avalanche Counters (PPACs), dedicated to the event-by-event tracking of the produced RIBs and to time of flight measurements and (b) the new high-granularity compact telescope array EXPADES (EXotic PArticle DEtection System), designed for nuclear physics and nuclear astrophysics experiments employing low-energy light RIBs. EXPADES consists of eight Δ E – E res telescopes arranged in a cylindrical configuration around the target. Each telescope is made up of two Double Sided Silicon Strip Detectors (DSSSDs) with a thickness of 40/60 μm and 300 μm for the Δ E and Eres layer, respectively. Additionally, eight ionization chambers were constructed to be used as an alternative Δ E stage or, in conjunction with the entire DSSSD array, to build up more complex triple telescopes. New low-noise multi-channel charge-sensitive preamplifiers and spectroscopy amplifiers, associated with constant fraction discriminators, peak-and-hold and Time to Amplitude Converter circuits were developed for the electronic readout of the Δ E stage. Application Specific Integrated Circuit-based electronics was employed for the treatment of the Eres signals. An 8-channel, 12-bit multi-sampling 50 MHz Analog to Digital Converter, a Trigger Supervisor Board for handling the trigger signals of the whole experimental set-up and an ad hoc data acquisition system were also developed. The performance of the PPACs, EXPADES and of the associated electronics was obtained offline with standard α calibration sources and in-beam by measuring the scattering process for the systems 17O+58Ni and 17O+208Pb at incident energies around their respective Coulomb barriers and, successively, during the first experimental runs with the RIBs of the EXOTIC facility.

The Silicon Vertex Trigger (SVT) is a processor developed at CDF experiment to perform online fast and precise track reconstruction. SVT is made of two pipelined processors, the Associative Memory, finding low precision tracks, and the Track Fitter, refining the track quality whith high precision fits. We will describe the architecture and the performances of a next generation track fitter, the GigaFitter, developed to reduce the degradation of the SVT efficiency due to the increasing instantaneous luminosity. The GigaFitter reduces the track parameter reconstruction to a few clock cycles and can perform many fits in parallel, thus allowing high resolution tracking at very high rate. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich in powerful DSP arrays. The FPGA is housed on a mezzanine board which receives the data from a subset of the tracking detector and transfers the fitted tracks to a Pulsar motherboard for the final corrections. Instead of the current 12 boards, one per sector of the detector, the final system will be much more compact, consisting of a single GigaFitter Pulsar board equipped with four mezzanine cards receiving the data from the entire tracking detector. Moreover, the GigaFitter modular structure is adequate to scale for much better performances and is general enough to be easily adapted to future High Energy Physics (HEP) experiments and applications outside HEP.

Real time event reconstruction plays a fundamental role in High Energy Physics experiments. The CDF experiment at the Tevatron collider performs a fast online reconstruction of high-resolution tracks using the Silicon Vertex Trigger (SVT). We will describe the architecture, the performance and the impact on CDF physics program of a next generation online track fitter, the GigaFitter, developed to improve the SVT track reconstruction efficiency as the Tevatron instantaneous luminosity increases. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich in powerful DSP arrays. The higher computation power allows to perform many tasks in parallel, reducing the track parameter reconstruction to a few clock cycles: as a result, the GigaFitter can perform more than one fit per nanosecond. The Gigafitter installation and commissioning were successfully completed in February 2010: 12 Track Fitter boards, one per each azimuthal sector of the silicon detector, have been replaced by a single Gigafitter board receiving the data from the entire tracking detector. Besides being much more compact and robust than the previous system, the Gigafitter increases the SVT track reconstruction efficiency and acceptance and copes more effectively with the high-occupancy events that occur frequently at the high luminosities the Tevatron currently delivers. Moreover, its architecture is general enough to be adapted to different experimental environments: the experience gained with the Gigafitter upgrade will be essential for future SVT-like tracking processor such as FTK at Atlas experiment.

Strong scientific motivation are pushing the second generation of ground base Cherenkov telescopes to lower as much as possible their energy threshold. MAGIC will be the biggest single telescope, in terms of collection area (250 m 2 ), foreseen for the second-half of 2001. The large collection area, the newphotodetector and the electronic design will allow the telescope to lower the energy threshold below 30 GeV. For this telescope a two-level pattern trigger is designed to work in severe high pixel rate. The MAGIC trigger architecture and its implementation is presented. # 2001 Elsevier Science B.V. All rights reserved. PACS: 95.55.Ka

The Gruneisen parameters γ τ of the most prominent τ phonons in CdSiP 2 , CuAlS 2 are presented. Concerning the sign and magnitude of γ τ , a separation into three groups of phonons can be observed. This result is compared with the γ values of the corresponding phonon branches of the analogue binaries in the zincblende structure. In addition, the τ phonon spectrum of CuGaS 2 is given.

We have measured in photoluminescence the energy shift of free, weakly and tightly bound excitons in high purity GaAs in magnetic fields up to 12T. In the weak binding limit we find a surprising result: the mass obtained from the magnetic shift is the electron-heavy hole reduced mass in contrast to the results obtained from k · p calculation in zincblende type semiconductors in zero magnetic field. In the tight binding limit the mass deduced from the magnetic shift is the effective electron mass.