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Abstract: This paper reports deuteron vector and tensor beam polarization measurements taken to investigate the systematic variations due to geometric beam misalignments and high data rates. The experiments used the In-Beam Polarimeter at the KVI-Groningen and the EDDA detector at the Cooler Synchrotron COSY at Jülich. By measuring with very high statistical precision, the contributions that are second-order in the systematic errors become apparent. By calibrating the sensitivity of the polarimeter to such errors, it becomes possible to obtain information from the raw count rate values on the size of the errors and to use this information to correct the polarization measurements. During the experiment, it was possible to demonstrate that corrections were satisfactory at the level of 10−5 for deliberately large errors. This may facilitate the real time observation of vector polarization changes smaller than 10−6 in a search for an electric dipole moment using a storage ring. [Copyright &y& Elsevier]

The static polarization of HD samples has been achieved using “brute force”, for HD samples purified by double distillation. Proton polarization in excess of 60% and deuteron vector polarization higher than 14% have been reached. It has been demonstrated that the ageing technique allows to get relaxation times at 1.5 K and 1 T larger than a week. It is advocated that the conventional dynamic polarization of HD should be feasible for the proton and the deuteron contained in the HD molecule. This would simplify considerably the machinery presently necessary to perform nuclear physics experiments with HD targets polarized by the static method. [Copyright &y& Elsevier]

A large acceptance lead-scintillator time-of-flight (TOF) wall has been developed to detect photons, neutrons, and charged particles produced in meson-photoproduction experiments on the proton and on the neutron. A TOF resolution of 600 ps and a position resolution of 11×18 cm2 (full-width at half-maximum) have been achieved. The wall has been successfully used in η and π+ photoproduction experiments as a photon and a neutron detector. This paper reports its design, calibration and performance. [Copyright &y& Elsevier]

We propose a calorimetry approach unconventional and innovative. The method is based on the measurement of the lateral distribution of charged particles around the shower axis, it has been used for the first time in the energy determination of Extensive Air Showers at very high energy (> 100 TeV) with single layer detector, providing an energy determination with resolution of about 10% for energies above 100 TeV. It has some peculiar characteristics which can be summarized in the following three points: (1) measurement of the shower energy by means of a single sampling; (2) calorimetry which renounces the classic concept of containment of the shower; (3) possibility to separate primary masses. In order to extend this technique at lower energies, specific simulations have been performed through GEANT4 in the energy range 100 GeV–10 TeV for different particles. [ABSTRACT FROM AUTHOR]

Abstract: In order to fully reconstruct to the reaction in the energy region of the meson production, new detectors along the ( ) beam line have to be installed in order to detect the scattered . The High Energy Tagger (HET) detector measures the deviation of leptons from their main orbit by determining their position and timing so to tag physics events and disentangle them from background. The HET detectors are placed at the exit of the dipole magnets, 11m away from the IP, both on positron and electron lines. The HET sensitive area is made up of a set of 28 plastic scintillators. A dedicated DAQ electronics board based on a Xilinx Virtex-5 FPGA have been developed for this detector. It provides a MultiHit TDC with a time resolution of the order of 500 ps and the possibility to acquire data any 2.5ns, thus allowing to clearly identify the correct bunch crossing. First results of the commissioning run are presented. [Copyright &y& Elsevier]

Abstract: We have designed and realized a Front-End chip for MPPC in standard CMOS technology. The channel presents a low input impedance in order to reduce as much as possible the recovery time of the sensor. This is achieved using the current domain for processing signals through the current conveyors (CCII) as building blocks of the channel. A current feed-back with low-pass filter has also been used to realize a sensitive improvement of the correction of the pile-up problem, in case of high repetition rate events. An independent arming threshold is available for each channel, providing the selection of the event through the peak level (proportional to the number of simultaneously hit pixels) reached by the signal. A constant-fraction functionality is present in order to reduce the well know time-walk problem. The delay in the correspondent branch is obtained by using an additional CCII block. The digital output of the discriminator channel has adjustable time width. The pilot chip is made up of five channels. All the values of the independent thresholds are stored in registers as well as the values of the trigger output width and the main polarization current of the CCII blocks. All the registers are writable from a standard three-wire SPI. These features make the chip fully self-consistent. In this work we present and discuss the simulation results together with the preliminary test performed. [Copyright &y& Elsevier]

Abstract: In recent works we presented the results of the characterization and the study of performance of several Silicon Photomultipliers delivered from MEPHI (Moscow Engineering and Physics Institute) and we proposed an electrical model of the SiPM to be used in analog simulations for the VLSI design of the pilot chip with technology produced. The results of the simulations was also presented. In this work we present the results of several test performed on the SiPM connected to the pilot chip. We also describe the prototype board with a micro-controller designed to adjust the parameters of the chip and to provide an adjustable and temperature controlled power supply to the SiPM. The results of the tests obtained allow us to refine the circuits design for the next chip. This chip has been developed inside the ALTCRISS and KLOE collaboration. [Copyright &y& Elsevier]

Abstract: In order to reconstruct physics events tagged with High Energy Tagger (HET) in the KLOE-2 (K LOng Experiment 2), we need to measure the Time Of Flight (TOF) of the electrons and positrons from the KLOE-2 Interaction Point (IP) to our tagging stations (11m apart). The required resolution must be better than the bunch spacing (2.7ns). We have developed and implemented on a Xilinx Virtex-5 FPGA a Time to Digital Converter (TDC) with 625ps resolution (LSB) along with an embedded data acquisition system and the interface to the online FARM of KLOE-2. We will describe briefly the architecture of the TDC and of the Data AcQuisition (DAQ) system. Some more details will be provided about the zero-suppression algorithm used to reduce the data throughput. [Copyright &y& Elsevier]