[en] Operation performance, algorithms, stability and physics results of the Outer em calorimeter of Focus are overviewed

[en] FINUDA is an experiment aiming at high resolution hypernuclear spectroscopy. It employs different types of detectors enclosed inside a large superconducting solenoid. It will operate on the new, high luminosity (e⁺ - e^-) collider DAPHINE of the INFN Frascati National Laboratory. The solenoid operates at 2765 A maximum current corresponding to a magnetic field of 1.1 T. The inner dimensions are: 2.4 m length, 2.7 m diameter. The coil within its cryostat is enclosed inside an iron return yoke composed by a central barrel and two end-caps which can be opened to access the inner detectors. The magnetic field in the inner volume has been fully mapped for both main and minor components. The alignment of such a magnet on a machine as DAPHINE is a very crucial item, needing particular care

[en] The simulated performances of a non-homogeneous e.m. calorimeter based on a 5 X tracking section using CsI(Tl) fibres, followed by a 10 X₀Pb-SCIFI head-on back section are reported. The study shows that such a technique is quite promising for the high-efficiency detection of photons in the energy range of interest at a φ-factory machine

[en] We report on the simulated performances of a non-homogeneous e.m. calorimeter based on a 5X₀ tracking section using CsI(Tl) fibres, followed by a 10X₀ Pb-SCIFI head-on back section. Our study shows that such a technique is quite promising for the high-efficiency detection of photons in the energy range of interest at a Φ-factory machine. (orig.)

[en] An array of 2424 2.6- m-long, 15- mm-diameter mylar straw tubes, arranged in two axial and four stereo layers, has been assembled at National Laboratories of Frascati of INFN for the FINUDA experiment. The array covers a cylindrical tracking surface of 18 m² and provides coordinate measurement in the drift direction and along the wire with a resolution of the order of 100 and 300 μm, respectively. The array has finished the commissioning phase and tests with cosmic rays are underway. The status straw tubes array and a very preliminary result from cosmic rays test are summarized in this work

[en] The FINUDA detector is a magnetic spectrometer optimized to study hypernuclear physics at DAΦNE. The tracking part of detector contains a large cylindrical array of 2424 straws which are 2.55 m long and are required to provide a space resolution of ∝100 μm. The FINUDA straw tube detector is now in an advanced phase of construction at National Laboratories of Frascati. The straw tube detector design, structural components, and readout electronics are presented in this work. A discussion of experimental results obtained from prototypes and treatment of systematic effects, inevitably present in the case of long straw tubes, is included. (orig.)

[en] This article reports on studies aimed to characterise the properties of plastic scintillating fibres to be used in head-on, 1:1 Pb-SCIFI calorimetric modules. The effect of glue on the attenuation of the light transported by cladding close to the photomultiplier tube is studied and found to effectively decrease the contribution of cladding light. Pb-SCIFI modules have been assembled and tested on a 20-80 MeV tagged photon beam. Good linearity and energy resolution better than 6%/√E[GeV] were achieved, therefore showing that this technique is suitable for experimentation at φ-factories. (orig.)

[en] A 9U VME like double threshold discriminator has been designed and constructed at Frascati INFN (National Institute of Nuclear Physics) laboratories. Its aim is to process the signals arising from gas drift chambers, introducing a very small time walk (∼ 650 ps.). Each discriminator board houses 32 channels. Each channel is located on an independent printed circuit mounted on socket. This solution is very convenient for replacing faulty channels without loosing operation of the full board

[en] An array of 2424 2.6 m-long, 15 mm-diameter mylar straw tubes, arranged in two axial and four stereo layers, has been assembled. The array covers a cylindrical tracking surface of 18 m² and provides coordinate measurement in the drift direction and along the wire. An under-standing of the systematic effects which are introduced by gravitational sag and electrostatics, thus dominating the detector performance especially with long straws, allows to determine wire position from drift-time distribution. The correction has been applied to reach a space resolution of 40 μm with DME, 100 μm with Ar + C₂H₆, and 100-200 μm with CO₂. Such a resolution is the best ever obtained for straws of these dimensions. A study of the gas leakage for the straw system has been performed, and results are reported. The array is being commissioned as a subdetector of the FINUDA spectrometer, and tracking performances are being studied with cosmic rays. (author)

[en] This article reports on studies aimed to characterise the properties of plastic scintillating fibres to be used in head-on, 1:1 Pb-SCIFI calorimetric modules. The effect of glue on the attenuation of the light transported by cladding close to the photomultiplier tube is studied and found to effectivaly decrease the contribution of cladding light. Pb-SCIFI modules have been assembled and tested on a 20-80 Mev tagged photon beam. Good linearity and energy resolution better than 6%/√E[GeV] were achieved, therefore showing that this technique is suitable for experimental at φ-factories