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A review of the two generations of front-end electronics for the muon spectrometer of the ALICE experiment at the Large Hadron Collider is presented. The basic elements of the front-end electronics ...are application-specific integrated circuits that are used in 1.1 × 10
6
measuring channels and devices for communication with the data-acquisition system. The first generation of the electronics operates in the trigger mode and is characterized by an input throughput of 3 × 10
3
events/s at an output data rate of 3.2 Gbit/s. The second generation is designed to operate under conditions of a high luminosity of the collider at input count rates of up to 10
5
events/s. Signal processing is performed in the continuous readout mode. The communication devices with the data-acquisition system use application-specific chips that provide optical communication with a data transfer rate of 0.8 Tbit/s
.
The measurement results of the front-end ASIC for the GEM detector read-out are presented. The MUCH ASIC v2 was designed and prototyped via Europractice by means of the 0.18 um CMOS MMRF process of ...UMC (Taiwan). The parameters of the analog channels, including the CSA, fast and slow shapers, discriminators, were measured. The channels provide a sufficient dynamic range of 100 fC, low power consumption of 10 mW per channel and ENC of 1550 el at a 50 pF detector capacitance.
The differential cross sections for small-angle proton elastic scattering on the
6,8,9,11Li nuclei at energies near 700 MeV/nucleon were measured in inverse kinematics using secondary nuclear beams ...at GSI Darmstadt. The hydrogen-filled ionization chamber IKAR was employed as target and recoil proton detector. For determining the nuclear matter radii and radial matter distributions, the measured cross sections have been analysed with the aid of the Glauber multiple-scattering theory. The nuclear matter distribution deduced for
11Li exhibits a very pronounced halo structure, the matter radius of
11Li being significantly larger than those of the
6,8,9Li isotopes. The data on
8,9Li are consistent with the existence of sizable neutron skins in these nuclei. The obtained data allow for a test of various theoretical model calculations of the structure of the studied neutron-rich nuclei.
A 64-channel readout and data-acquisition module is described in detail. It consists of an H12700 multianode photomultiplier tube, four PADIWA preamplifier boards, and a TRB v3 card that perform the ...functions of a time-to-digital converter and a data concentrator. The software modules that are necessary for operation of the prototype are described. The inter-channel delays are calibrated. The drift of individual delays does not exceed 0.5 ns for the entire measurement time. The spectra of the “time over threshold” (ToT) are investigated. The influence of periodic noise pickups and the need to improve circuit designs are revealed. The timing properties of the wavelength shifter and its effect on the detection efficiency for Cherenkov rings are investigated. The most intense component is characterized by a decay time of 1.1 ns and there are components with characteristic times of 3.8 and 45 ns. The influence of single-electron spectrum features on the detection efficiency for photoelectrons and the probability of false hits are determined. The total time resolution of 131 channels is 1.1 ns (FWHM). The results make it possible to use the investigated system of readout and data acquisition in the CBM experiment. Nevertheless, the elimination of the revealed shortcomings will provide the efficiency margin and improve the reliability of the system during long-term operation.
Luminosity-driven channeling extraction has been observed for the first time in a 900 GeV study at the Fermilab Tevatron. This experiment, Fermilab E853, demonstrated that useful TeV level beams can ...be extracted from a superconducting accelerator during high luminosity collider operations without unduly affecting the background at the collider detectors. Multipass extraction was found to increase the efficiency of the process significantly. The beam extraction efficiency was about 25%. Studies of time dependent effects found that the turn-to-turn structure was governed mainly by accelerator beam dynamics. Based on the results of this experiment, it is feasible to construct a parasitic 5–10 MHz proton beam from the Tevatron collider.
Performance of the gas-filled detector prototypes based on the GEM, TGEM, and Micromegas technologies was studied on the test beam of the CERN PS accelerator. Three-component mixtures based on Ar and ...He were used as the working gas. For all tested detector prototypes, the gas amplification factors were measured, and the detection efficiencies, cluster distributions, and the radii of the charge cloud collected on the readout electrode were estimated.
Tests of the CBM Rich readout and Daq prototype Adamczewski-Musch, J.; Akishin, P.; Becker, K. -H. ...
Physics of particles and nuclei letters,
11/2017, Letnik:
14, Številka:
6
Journal Article
Recenzirano
The CBM RICH detector is an integral component of the future CBM experiment at FAIR, providing efficient electron identification and pion suppression necessary for the measurement of rare dileptonic ...probes in heavy ion collisions. An overview of the CBM RICH readout and DAQ system prototype is given, consisting of the PADIWA preamplifier-discriminator board, the TDC-HUB board TRBv3, and DAQ and analysis code in the CbmRoot framework. The laboratory setup built for studying the timing characteristics of the readout chain and the analysis results obtained using the laboratory measurements are presented. The fine time calibration and inter-channel delay correction techniques and their implementation and effect are discussed.
This paper presents a review of studies on the spatial structure of light exotic nuclei performed by the PNPI-GSI collaboration. A series of experiments has been carried out in beams of exotic nuclei ...with an energy of 0.7 GeV/nucleon at the Helmholtz Center for Heavy Ion Research (GSI, Darmstadt), in which the differential cross sections for proton–nucleus small-angle scattering in inverse kinematics have been measured using the ionization spectrometer IKAR developed at PNPI. An analysis of the measured cross sections has allowed us to determine the nuclear matter distributions in the studied nuclei of the He, Li, Be, B, and C isotopes and also to determine the halo sizes in
6
He,
11
Li,
14
Be,
8
B, and
15
C nuclei.
Since 1975 proton beam of PNPI synchrocyclotron with fixed energy of 1000 MeV is used for the stereotaxic proton therapy of different head brain diseases. 1300 patients have been treated during this ...time. The advantage of high energy beam (1000 MeV) is low scattering of protons in the irradiated tissue. This factor allows to form the dose field with high edge gradients (20%/mm) that is especially important for the irradiation of the intra-cranium targets placed in immediate proximity to the life critical parts of the brain. Fixation of the 6 0mm diameter proton beam at the isodose centre with accuracy of ±1.0 mm, two-dimensional rotation technique of the irradiation provide a very high ratio of the dose in the irradiation zone to the dose at the object′s surface equal to 200:1. The absorbed doses are: 120-150 Gy for normal hypophysis, 100-120 Gy for pituitary adenomas and 40-70 Gy for arterio-venous malformation at the rate of absorbed dose up to 50 Gy/min. In the paper the dynamics and the efficiency of 1000 MeV proton therapy treatment of the brain deceases are given. At present time the feasibility study is in progress with the goal to create a proton therapy on Bragg peak by means of the moderation of 1000 MeV proton beam in the absorber down to 200 MeV, energy required for radiotherapy of deep seated tumors.
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