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[en] The electronics of the data acquisition system based on silicon photomultipliers is briefly described. The elements and modules of the system were designed and constructed at ITEP especially for the DANSS detector. Examples of digitized signals obtained with the presented electronic modules and selected results on processing of the DANSS engineering data-taking run in spring 2016 are given.
[en] The KM3NeT neutrino telescope is being built on the Mediterranean sea and, once completed, it will be composed by tens of thousands of glass spheres (nodes) including each 31 of small photocathode (3”). The readout and data acquisition system of KM3NeT has to collect, treat and send to shore, in an economic way, the enormous amount of data produced by the photomultipliers and at the same time to provide time synchronization between each node at the level of 1 ns. It is described in the present article all the electronics developed for achieving this goal.
[en] In this work, modernized data acquisition systems of the Andyrchi and Carpet-3 shower facilities with automated data preprocessing and data transmission systems to the observatory of the Terskol Branch of the Institute of Astronomy are described. To solve joint problems on searching transient sources, data from the Andyrchi and Carpet facilities are processed and transmitted to the observatory of the Terskol Branch of the Institute of Astronomy in the form of astronomic coordinates for observations with an optical telescope.
[en] The design idea of multi-sub-station and distributed intelligent electrode is adopted in the LQC-II-type 3D resistivity data acquisition system, which results in a multi-channel fast parallel acquisition. The combination of 16 sub-stations can reach large exploration depth. The basic principle, working method and technology of the system generally were discussed in this paper. Field experiment and three-dimensional inversion of measured data with the instrument were carried out, the interpreted results of horizontal direction and vertical slice inosculated well with borehole data. (authors)
[en] The objective of the Baikal-GVD project is the construction of a km3-scale neutrino telescope in Lake Baikal. The Gigaton Volume Detector consists of a large three-dimensional array of photo-multiplier tubes. The first GVD-cluster has been deployed and commissioned in April 2015. The data acquisition system (DAQ) of the detector takes care of the digitization of the photo-multiplier tube signals, data transmission, filtering and storage. The design and the implementation of the data acquisition system are described.
[en] The objective of this study is to demonstrate in vivo the feasibility of optoacoustic temperature imaging during cryotherapy of prostate cancer. We developed a preclinical prototype optoacoustic temperature imager that included pulsed optical excitation at a wavelength of 805 nm, a modified clinical transrectal ultrasound probe, a parallel data acquisition system, image processing and visualization software. Cryotherapy of a canine prostate was performed in vivo using a commercial clinical system, Cryocare® CS, with an integrated ultrasound imaging. The universal temperature-dependent optoacoustic response of blood was employed to convert reconstructed optoacoustic images to temperature maps. Optoacoustic imaging of temperature during prostate cryotherapy was performed in the longitudinal view over a region of 30 mm (long) × 10 mm (deep) that covered the rectum, the Denonvilliers fascia, and the posterior portion of the treated gland. The transrectal optoacoustic images showed high-contrast vascularized regions, which were used for quantitative estimation of local temperature profiles. The constructed temperature maps and their temporal dynamics were consistent with the arrangement of the cryoprobe and readouts of the thermal needle sensors. The temporal profiles of the readouts from the thermal needle sensors and the temporal profile estimated from the normalized optoacoustic intensity of the selected vascularized region showed significant resemblance, except for the initial overshoot, that may be explained as a result of the physiological thermoregulatory compensation. The temperature was mapped with errors not exceeding ±2 °C (standard deviation) consistent with the clinical requirements for monitoring cryotherapy of the prostate. In vivo results showed that the optoacoustic temperature imaging is a promising non-invasive technique for real-time imaging of tissue temperature during cryotherapy of prostate cancer, which can be combined with transrectal ultrasound—the current standard for guiding clinical cryotherapy procedure. (paper)
[en] The nuclear matter, which constitutes the atomic nuclei, is composed of quarks and gluons and interactions between them are described by quantum chromo-dynamics (QCD). Under ordinary conditions, quarks and gluons cannot be observed isolated and are confined inside hadrons such as protons and neutrons. The Quark-Gluon Plasma (QGP) is a state of nuclear matter predicted by QCD where quarks and gluons are deconfined. Experimentally, a QGP can be created in ultra-relativistic heavy ion collisions such as the lead-lead collisions delivered at the LHC, corresponding to speeds close to the speed of light. It is possible to obtain information on the characteristics of the QGP by measuring a large number of observables. In particular, the production of charmonium states such as the J/Ψ and the Ψ(2S), heavy particles composed of a charm and anti-charm pair, is studied to investigate the plasma. Indeed, the presence of QGP is expected to modify the charmonium production yields, due to a balance between the mechanism of color screening of the charm quark potential and a mechanism called recombination. This balance depends on the collision energy, the temperature of the plasma and nature on the considered particle, in particular one expects the Ψ(2S) to be more suppressed than the J/Ψ. In this thesis the inclusive production of Ψ(2S) in Pb - Pb collisions at an energy per nucleon-nucleon collision in the center of mass frame of TeV is measured in the dimuon-decay channel, using the ALICE Muon Spectrometer. The analysis is based on the data collected in ALICE (A Large Ion Collider Experiment) at the LHC in 2015 with an integrated luminosity of 225 μb-1. The nuclear modification factor RAA is studied as a function of centrality. The ratio of the Ψ(2S) and J/Ψ RAA is also evaluated and shows that the Ψ(2S) is more suppressed than the J/Ψ for mid-central and central events. Compared with theoretical predictions, the measurements are, within uncertainty, in agreement with theoretical model. The upgrade of the Muon Trigger, the MID (Muon Identifier), is also studied, in particular the expected data flow at a collisions rate of 100 kHz. Based on the Pb - Pb data at a collision energy of TeV, the estimations predict that the technology that will be implemented in the MID provides a sufficient bandwidth to sustain the data flow. (author)
[fr]La matiere nucleaire, constituant le noyau des atomes, est formee de quarks et de gluons, dont l'interaction est decrite par la theorie de la chromodynamique quantique (QCD). Dans des conditions normales, quarks et gluons ne peuvent etre observes de facon isolee et sont confines dans des hadrons tels que les protons et les neutrons. Le Plasma de Quarks et de Gluons (PQG) est un etat de la matiere nucleaire predit par la QCD pour lequel ces quarks et gluons sont deconfines. Experimentalement, le PQG peut etre cree dans des collisions d'ions lourds ultra-relativistes, telles que les collisions d'ions lourds effectuees au LHC, correspondant a des vitesses proche de celle de la lumiere. Il est possible d'obtenir des informations sur le PQG en mesurant un large nombre d'observables. En particulier, la production de charmonium tels que le J/Ψ et le Ψ(2S), particules lourdes constituees d'une paire de quarks charme et anti-charme est mesuree pour etudier le plasma. En effet, la presence d'un PQG est censee modifier les taux de production des charmonia, a cause d'un equilibre entre un mecanisme d'ecrantage de couleur du potentiel des quarks charme et un mecanisme dit de recombinaison. La position de cet equilibre depend de l'energie de collision, la temperature du plasma, et la nature de la particule consideree, et plus specifiquement, il est attendu que le Ψ(2S) soit plus supprime que le J/Ψ. Dans cette these, la production inclusive de Ψ(2S) en collisions Pb - Pb a une energie par collision nucleon-nucleon dans le referentiel du centre de masse de TeV est mesuree dans le canal de decroissance de dimuon avec le Spectrometre a Muons d'ALICE. L'analyse est basee sur les donnees collectees dans ALICE (A Large Ion Colider Experiment) au LHC en 2015 correspondant a une luminosite integree de 225 μb-1. Le facteur de modification nucleaire RAA est etudie en fonction de la centralite des collisions, correspondant a la distance transverse entre les centre des noyaux de plomb. Le rapport des RAA du Ψ(2S) et du J/Ψ est egalement mesure et montre que le Ψ(2S) est plus supprime que le J/Ψ pour des collisions mi-centrales et centrales. Comparees aux predictions theoriques, les mesures sont compatibles avec les modeles dans la limite des incertitudes. L'amelioration du Muon Trigger, le MID, est egalement etudie, en particulier le debit de donnees attendu pour des frequences de collision de 100 kHz. Basee sur les donnees en collisions Pb - Pb a une energie de TeV, les estimations predisent que la technologie qui sera implementee sur le MID possede une bande passante suffisante.
[en] The paper presents a design and construction of a pulse generator for testing of high-resolution nuclear spectroscopy systems based on new method for providing pulses of accurately predetermined amplitudes as well as pulses with uniform amplitude distributions. A stable and accurate pulse generator prototype has been developed based on the new method of DAC Interpolation as described in paper. The system produces the pulses forming uniform amplitude distribution with 1 microvolt step size. It is suitable for calibration of spectroscopy systems with the resolution that can be as high as 16-bit (64K). Precision pulses are produced with 16-bit resolution with adjustable rise time and fall time. Pulse duration ranges from 500 nanoseconds to 100 microseconds. The system is designed using commercially available components such as multiplying DAC and resistor string DAC. The hardware design details and test results are reported in the paper. The pulses with precision amplitudes and uniformly distributed amplitudes can be used for testing of Integral Non-Linearity (INL) and Differential Non-Linearity (DNL) of spectroscopy systems respectively. It is possible to generate any predetermined pulse amplitude distribution using this hardware. The pulse generation system provides import substitution for commercially available imported models. (author)
[en] This thesis is focused on the study of the front-end electronics for one of the large high altitude air shower observatory (LHAASO) detectors, which is the wide field of view Cherenkov telescope array (WFCTA). It covers six main topics from the physical simulation to the implementation of the data acquisition system. First, the principles of cosmic rays and the situation of the LHAASO experiment were reviewed and presented as the foundation of our discussion. Then, physics simulations were made to understand the propagation of cosmic rays in the atmosphere and to figure out the characteristics of the input signal of the electronics. These simulations were also used to deepen the understanding of the specifications of the telescope and to cross-check them. Next, a new PMT model was successfully built to be used for both physical and electronic simulations. This new model and another four different PMT models were compared and discussed in details to reveal their advantages and disadvantages. By using this PMT model, the behavior models for the designs based on the classical electronics and application-specific integrated circuit (ASIC) were built and studied. Both solutions fit the requirements of the telescope, but considering the development of the micro-electronics, the electronics of the future and high-performance telescopes should be based on the ASICs. After that, the selected ASIC, which is PARISROC 2, was evaluated by using the existing application boards. The results showed that those designs cannot fully demonstrate the true performance of the chip. Therefore, a prototype LHAASO-oriented front-end electronic board that is based on ASIC was designed, implemented and fabricated. Several modifications and enhancements were made to improve the performance of the new design. A detailed description of the development is presented in the thesis. Finally, a series of tests have been performed to verify the concept of the design and to evaluate the application board. The preliminary results show the good general performance of the ASIC and that this design nearly meets the specifications of the WFCTA. (author)
[fr]Le travail de these porte sur l'etude de l'electronique front-end pour le telescope WFCTA (Wide Field of View Cherenkov Telescope Array,) qui est l'un des detecteurs de l'observatoire LHAASO (Large High Altitude Air shower Observatory). Le manuscrit de these couvre six themes principaux allant de la simulation physique au developpement d'un nouveau systeme d'acquisition de donnees. Tout d'abord, les principes de la physique des rayons cosmiques et de l'experience LHAASO sont presentes donnant ainsi une introduction sur les sujets discutes dans la these. Des simulations ont ete faites dans le but de comprendre la propagation des rayons cosmiques dans l'atmosphere et d'en deduire les caracteristiques du signal d'entree de l'electronique. Ces simulations ont egalement ete utilisees pour approfondir la comprehension des specifications du telescope et de les verifier. Un nouveau modele de PMT a ete elabore pour etre utilise dans les simulations. Ce nouveau modele est compare aux autres modeles de PMT. Des modeles d'electronique pour les conceptions basees sur les composants electroniques classiques et sur l'ASIC (Application-specific Integrated Circuit) sont construites et etudiees. Ces deux solutions remplissent les specifications du telescope WFCTA. Neanmoins, compte tenu du developpement de la micro-electronique, il est propose que l'electronique des telescopes de haute performance devrait etre basee sur l'ASIC.L'ASIC selectionne, PARISROC 2, est evalue en utilisant des bancs de tests existants. Les resultats montrent que ces bancs de tests ne peuvent pas demontrer pleinement la veritable performance de l'ASIC. Par consequent, une carte electronique front-end prototype qui est basee sur ASIC a ete concue et fabriquee. Plusieurs modifications ont ete apportees pour ameliorer la performance de la nouvelle carte. Une description detaillee de ce developpement est presentee dans la these. Un nouveau systeme d'acquisition de donnees a egalement ete concu pour ameliorer la capacite de lecture de donnees dans le banc de tests de la carte front-end. Enfin, une serie de tests ont ete effectues pour verifier le concept de design et pour evaluer la performance de la carte front-end. Ces resultats montrent la bonne performance generale de l'ASIC PARISROC 2 et que la carte front-end repond globalement aux specifications de la WFCTA. Base sur les resultats de ce travail de these, un nouveau ASIC, mieux adapte pour les telescopes de type WFCTA, a ete concu et est actuellement en cours de fabrication. (auteur)