Designs of hodoscopes of nuclear fragments based on quartz and scintillation plates with light pickup by silicon avalanche photodiodes are described. Hodoscopes are planned for use in the BM@N ...experiment for registration of heavy nuclear fragments near the axis of the heavy ion beam. The results of measurements of light yields in detector elements based on quartz and scintillation plates on the electron beam of the synchrotron "Pakhra" (LPI) are presented. The measured nonuniformity of the light collection shows that readout from both sides of hodoscope detector elements is needed.
Two versions of a forward hodoscope have been developed and manufactured based on scintillation and radiation-resistant quartz plates. The hodoscopes are designed to register ions in the BM @ N ...experiment at the NICA accelerator complex. The light outputs and their inhomogeneity were measured as a function of the coordinates of the passage of particles through the hodoscope plates on the calibration beam of the secondary electrons of the “Pakhra” synchrotron of the Lebedev Physical Institute.
Beam test of FARICH prototype with digital photon counter Barnyakov, A.Yu; Barnyakov, M.Yu; Bobrovnikov, V.S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2013, Letnik:
732
Journal Article
Recenzirano
In June 2012 we tested a Focusing Aerogel RICH detector prototype based on Digital Photon Counters (DPC) by Philips at the CERN PS T10 beam line with a particle momentum up to 6GeV/c. The prototype ...comprises a 20×20cm2 photon detector with 48×48 DPC pixels. In order to reduce the dark count rate, the photon detector was cooled to −40°C in addition to disabling individual DPC's microcells. A four layer focusing aerogel radiator with 200mm focal distance was studied. We obtained a Cherenkov angle resolution of 3.61±0.04mrad. The mean number of photoelectrons in a ring is 12. Directly measured π/K separation at 6GeV/c momentum is 3.5σ, μ/π separation is 5.3σ at 1GeV/c. A comparison with a Monte Carlo simulation is presented as well.
•Focusing Aerogel RICH prototype with Digital Photon Counters by Philips was built.•The prototype was tested at the CERN PS T10 beam line.•We observed Cherenkov rings with 12 photoelectrons in average.•Timing resolution of DPCs is 48ps for single photons.•Cherenkov angle resolution is 3.64±0.04mrad per ring.
The cross sections of forward emission of one, two and three neutrons by 158A GeV 115In nuclei in collisions with Al, Cu, Sn and Pb targets are reported. The measurements were performed in the ...framework of the ALICE–LUMI experiment at the SPS facility at CERN. Various corrections accounting for the absorption of beam nuclei and produced neutrons in target material and surrounding air were introduced. The corrected cross section data are compared with the predictions of the RELDIS model for electromagnetic fragmentation of 115In in ultraperipheral collisions, as well as with the results of the abrasion–ablation model for neutron emission in hadronic interactions. The measured neutron emission cross sections well agree with the RELDIS results, with the exception of In–Al collisions where the measured cross sections are larger compared to RELDIS. This is attributed to a relatively large contribution of hadronic fragmentation of In on Al target with respect to electromagnetic fragmentation, in contrast to similar measurements performed earlier with 30A GeV 208Pb colliding with Al.
ALICE T0 detector Bondila, M.; Grigoriev, V.A.; Guber, F.F. ...
IEEE transactions on nuclear science,
10/2005, Letnik:
52, Številka:
5
Journal Article
Recenzirano
T0-the fast timing and trigger detector for the ALICE experiment at CERN LHC-is described. Performance of the T0 prototype measured with a mixture of 6 GeV/c negative pions and kaons is given. The ...best time resolution (28 ps r.m.s.) was reached with a radiator diameter matching that of the photocathode. The results for all the tested radiator sizes are considerably better than 50 ps-the minimum requirement for the ALICE experiment.
Analysis of fast timing and trigger Cherenkov detector's design for its use in collider experiments is presented. Several specific requirements are taken into account - necessity of the radiator's ...placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator's design. Characteristics of the Cherenkov detector's laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of obtaining sufficiently high geometrical efficiency along with good enough time resolution (50 ps sigma).
Aerogel has been successfully used as a radiator in Cherenkov detectors. In 2004, a multilayer aerogel providing Cherenkov ring focusing was proposed and produced. FARICH (Focusing Aerogel Rich ...Imaging CHerenkov) detectors such as ARICH for Belle-II (KEK, Japan), Forward RICH for PANDA detector (FAIR, Germany), and FARICH for the Super Charm-Tau factory project (BINP, Novosibirsk) have been developed based on this aerogel. Prototypes of FARICH detector based on MRS APD and Philips DPC photosensors were developed and tested in the framework of this project. An angular resolution for Cherenkov rings of 3.6 mrad was achieved.
Tests of FARICH prototype with precise photon position detection Barnyakov, A.Yu; Barnyakov, M.Yu; Basok, I.Yu ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2014, Letnik:
766
Journal Article
Recenzirano
In June 2012 a FARICH prototype from Philips Digital Photon Counting (PDPC) based on a photon camera with dimensions of 200200 mm has been tested at CERN. Remarkable particle separation has been ...achieved with a 4-layer aerogel sample: the pi /K separation at a 6 GeV/c momentum is 3.5 sigma , the mu / pi mu / pi separation is 5.3 sigma at 1 GeV/c. The analysis of the data has shown that the main contribution to the accuracy of the ring radius measurement comes from aerogel. The development of focusing aerogels is proceeding in two main directions: tuning of production technology of multilayer blocks and development of a new production method with continuous density (refractive index) gradient along the block depth. The beam test was carried out in December 2012-January 2013 at the electron beam test facility at the VEPP-4 M e super(+)e super(-) collider. The goal of this test was to measure different single layer and focusing aerogel samples, both multilayer and gradient. Aerogel samples were tested with a PDPC FARICH prototype. A part of DPC SPADs in each pixel was disabled to form an active area of 11 mm super(2). The collected data proved that gradient aerogel samples focus Cherenkov light.
Preliminary results of research into electron multiplication in micropattern gas detectors (MPGDs) at a high level of alpha-particle background are presented. This work has expanded the borders of ...understanding of the streamer mode nature. It is seen as a complex of electrostatic and electromagnetic interactions which begin the appearance of the precursor in plasma state. In an inter-electrode gap, plasma oscillations occur which are accompanied by longitudinal elastic waves of ionization, which can reach the cathode surface with an induced negative charge. With the release of this charge, due to the previously established conducting channel, there is a strong pulse accompanied by emission due to the recombination of positive and negative ions and a thin cord or streamer. With the aim of protecting the MPGDs from spark breakdown at a high-level alpha-particle background, the following gas composition of buffer, cooling, and electronegative components is offered: 70% He + 28% CF
4
+ 2% SF
6
.
Retgem with polyvinylchloride electrodes Razin, V. I.; Reshetin, A. I.; Filippov, S. N.
Instruments and experimental techniques (New York),
09/2011, Letnik:
54, Številka:
5
Journal Article
Recenzirano
This paper presents a new design of Gas Electron Multiplier (GEM) based on electrodes made of polyvinylchloride plastic (PVC)-Resistive Electrode Thick GEM (RETGEM). Our device can operate with the ...gain up to 10
5
as a conventional GEM at low counting rates and as RPC (Resistive Plate Counter) in case of high counting rates without the transit to the violent sparks. The distinct feature of present RETGEM is the absent of the metal coating and lithographic technology for manufacturing of the protective dielectric rims. The electrodes made of PVC permit us to make the holes by a simple drilling machine. RETGEM-like detectors could be useful in many fields of application requiring a cheaper manufacturing and safer operation, for example, in large neutrino experiments, in TPC, RICH systems, etc.
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