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FARCOS is a modular detection system intended to boost the capacity of 4π detectors towards correlation measurements. The final FARCOS system will be composed of 20 telescopes, each formed by two Si layers of 32-ch orthogonal Double Sided Silicon Strip Detectors and one calorimeter stage composed by 4 CsI(Tl) tronco-pyramidal scintillator crystals readout by a Si photodiode. The paper focuses on the first application of the FARCOS detection array in the present configuration of 10 telescopes in a real experiment, the CHIFAR experiment and discusses the main instrumental features relevant for the experiments.

The FARCOS (Femtoscope ARray for Correlation and Spectroscopy) collaboration is finally going to instrument the first batch of 10-12 telescopes. They are capable of reconstructing the particle’s momentum with a high degree of precision and of performing correlation measurements of Light Charged Particles (LCPs) and of LCPs and Intermediate Mass Fragments thanks to the very good energy and angular and resolution. Each telescope features a sensitive area of 6.4 × 6.4 cm2 and is composed of three detection stages: two Si layers and a CsI(Tl) calorimeter. The FARCOS cluster modularity allows the arrangement in different configurations, depending on the physics case one wants to address. The final system will be a modular assembly of 20 telescopes. The total number of readout channels for the final FARCOS system is 2560 channels for the silicon layers and 80 channels for the scintillators. In this paper, we focus on the FARCOS basic module and system architecture and illustrate its performance as assessed in test beams in true experimental conditions.

Few years ago we proposed a novel detection system textbf- named FARCOS (Femtoscopy ARray for COrrelations andSpectroscopy) – to target different open cases in nuclear physics. The basic cluster unit of the FARCOS array is a telescope structure with an active area of $6.4 \times 6.4$ cm$^{\mathbf {2}}$ composed of three detection stages. The first two detection layers are DC-coupled Double-Sided Silicon Strip Detectors (DSSSDs), 300 $\mu \textbf{m}$ thick and 1500 $\mu \textbf{m}$ thick, featuring $32 \times 32$ orthogonal strips. The third stage, acting as calorimeter, is composed of four truncated pyramids of CsI(Tl) crystals with an active area of $3.2 \times 3.2$ cm$^{\mathbf {2\, }}$textbfand an absorption length of 6 cm arranged in window configuration. The final system will be a modular assembly of 20 telescopes.A key feature of FARCOS is the identification of the particles stopping even in the first detection layer, relying on pulse shape analysis techniques. The FARCOS frontend electronics features a full scale energy range up to 2 GeV with 5 different selectable ranges and an energy resolution down to 10 keV FWHM with a power budget of about 10 mW/channel in the case of the lower full scale energy range. Its core is a custom multichannel charge preamplifier VLSI chip.The system performance has been extensively qualified on few workhorses in view of the assembly of the final telescopes foreseen for 2018.

In this paper we report on a new powerful and self-consistent analysis technique aimed in order to get information online on laser generated plasmas. Performance of the method has been carried out during two set of measurement by using two different lasers. The first set of data has been collected at LENS Laboratory of INFN-LNS in Catania by using a laser which produces pulses having energies of 2 J and temporal duration of 6 ns, while the second set of data has been collected at ILIL of INO-CNR in Pisa with a laser system capable of delivering pulses of up to 10 mJ in 40 fs.

A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition. The signals from a typical CHIMERA detector cell are collected both using a standard CHIMERA electronic chain, up to the amplifier, and directly from the preamplifier. The preliminary on-beam results are presented.

We have designed, built, and tested an on-line pre-analysis and data-storage unit for the data acquisition system of the 4/spl pi/-detector CHIMERA. The unit uses special algorithms to perform particle identification and automatic peak detection. It tags in charge each event and stores the results on external unit, together with the raw data. It consists of two commercial 2 GHz workstations connected together through 1 Gb/s Ethernet boards and to the data acquisition system through a 100 Mb/s Ethernet.