The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform
L Consiglio - One of the best experts on this subject based on the ideXlab platform.
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muography with Nuclear Emulsions stromboli and other projects
Annals of Geophysics, 2017Co-Authors: V Tioukov, P. Strolin, L Consiglio, C. Bozza, Giovanni De Lellis, A Sheshukov, M Orazi, R Peluso, Chiara De Sio, S M StellacciAbstract:The muon radiography is a novel imaging technique to probe the volcanoes interior, using the capability of high energy cosmic ray muons to penetrate large thicknesses of rock. In this way it is possible to derive a 2D density map along the muon trajectory of volcanic edifices and deduce information on the variations in the rock density distribution, like those expected from dense lava conduits, or low density magma supply paths. This method is applicable also to study geological objects as glaciers, faults, oil underground reservoirs, engineering constructions, where a density contrast is present. Nuclear Emulsions are well suited to be employed in this context for their excellent angular resolution; they are compact and robust detectors, able to work in harsh environments without need of power supply. On the other side, a long exposure time is required for a reasonable detector surface (~10 m 2 ) in order to collect a sufficient statistics of muons, and a quasi-real time analysis of the emulsion data is rather difficult due to the scanning time needed by the optical microscopes. Such drawback is on the way to be overcome thanks to a recent R&D program on ultra-fast scanning systems. Muon radiography technique, even if limited to the summit part of the volcano edifice, represents an important tool of investigation, at higher spatial resolution, complementary to the conventional geophysics techniques. The first successful result in this field was obtained by a Japanese group that observed in 2007 the conduit structure of Mt. Asama. Since 2010, other interesting volcanoes have been probed with the same method: Stromboli in 2011, Mt. Teide in 2012 and La Palma in 2014. Here we discuss the muon imaging technique reporting the Nuclear emulsion detector design exposed at Stromboli and results of the data analysis.
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a new generation scanning system for the high speed analysis of Nuclear Emulsions
Journal of Instrumentation, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, G Galati, A Lauria, M C Montesi, V TioukovAbstract:The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting Nuclear Emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of Nuclear Emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.
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NEWS: Nuclear Emulsions for WIMP Search
arXiv: Instrumentation and Methods for Astrophysics, 2016Co-Authors: A. B. Aleksandrov, T Asada, A. M. Anokhina, D. Bender, I. Bodnarchuk, Annarita Buonaura, Salvatore Buontempo, M. M. Chernyavskii, A. Chukanov, L ConsiglioAbstract:Nowadays there is compelling evidence for the existence of dark matter in the Universe. A general consensus has been expressed on the need for a directional sensitive detector to confirm, with a complementary approach, the candidates found in conventional searches and to finally extend their sensitivity beyond the limit of neutrino-induced background. We propose here the use of a detector based on Nuclear Emulsions to measure the direction of WIMP-induced Nuclear recoils. The production of Nuclear emulsion films with nanometric grains is established. Several measurement campaigns have demonstrated the capability of detecting sub-micrometric tracks left by low energy ions in such emulsion films. Innovative analysis technologies with fully automated optical microscopes have made it possible to achieve the track reconstruction for path lengths down to one hundred nanometers and there are good prospects to further exceed this limit. The detector concept we propose foresees the use of a bulk of Nuclear emulsion films surrounded by a shield from environmental radioactivity, to be placed on an equatorial telescope in order to cancel out the effect of the Earth rotation, thus keeping the detector at a fixed orientation toward the expected direction of galactic WIMPs. We report the schedule and cost estimate for a one-kilogram mass pilot experiment, aiming at delivering the first results on the time scale of six years.
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Intrinsic neutron background of Nuclear Emulsions for directional Dark Matter searches
Astroparticle Physics, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, T Asada, N. D'ambrosio, A. Di Crescenzo, N. Di Marco, M. L. Di Vacri, S. FuruyaAbstract:Recent developments of the Nuclear emulsion technology led to the production of films with nanometric silver halide grains suitable to track low energy Nuclear recoils with submicrometric length. This improvement opens the way to a directional Dark Matter detection, thus providing an innovative and complementary approach to the on-going WIMP searches. An important background source for these searches is represented by neutron-induced Nuclear recoils that can mimic the WIMP signal. In this paper we provide an estimation of the contribution to this background from the intrinsic radioactive contamination of Nuclear Emulsions. We also report the neutron-induced background as a function of the read-out threshold, by using a GEANT4 simulation of the Nuclear emulsion, showing that it amounts to about 0.06 per year per kilogram, fully compatible with the design of a 10 kg × year exposure.
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a new fast scanning system for the measurement of large angle tracks in Nuclear Emulsions
Journal of Instrumentation, 2015Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, N Di Marco, G Galati, A Lauria, M C MontesiAbstract:Nuclear Emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, Nuclear Emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use Nuclear Emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.
A Buonaura - One of the best experts on this subject based on the ideXlab platform.
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Discovery potential for directional Dark Matter detection with Nuclear Emulsions
The European Physical Journal C, 2018Co-Authors: N. Agafonova, A Buonaura, T Asada, I. Bodnarchuk, A. Chukanov, A. Aleksandrov, A. Anokhina, V. v. Ashikhmin, M. Chernyavskii, N. D’ambrosioAbstract:Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for Nuclear recoils induced by the scattering of Weakly Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also prove the galactic origin of Dark Matter with an unambiguous signal-to-background separation. Indeed, the angular distribution of recoiled nuclei is centered around the direction of the Cygnus constellation, while the background distribution is expected to be isotropic. Current directional experiments are based on gas TPC whose sensitivity is limited by the small achievable detector mass. In this paper we present the discovery potential of a directional experiment based on the use of a solid target made of newly developed Nuclear Emulsions and of optical read-out systems reaching unprecedented nanometric resolution.
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a new generation scanning system for the high speed analysis of Nuclear Emulsions
Journal of Instrumentation, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, G Galati, A Lauria, M C Montesi, V TioukovAbstract:The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting Nuclear Emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of Nuclear Emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.
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Intrinsic neutron background of Nuclear Emulsions for directional Dark Matter searches
Astroparticle Physics, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, T Asada, N. D'ambrosio, A. Di Crescenzo, N. Di Marco, M. L. Di Vacri, S. FuruyaAbstract:Recent developments of the Nuclear emulsion technology led to the production of films with nanometric silver halide grains suitable to track low energy Nuclear recoils with submicrometric length. This improvement opens the way to a directional Dark Matter detection, thus providing an innovative and complementary approach to the on-going WIMP searches. An important background source for these searches is represented by neutron-induced Nuclear recoils that can mimic the WIMP signal. In this paper we provide an estimation of the contribution to this background from the intrinsic radioactive contamination of Nuclear Emulsions. We also report the neutron-induced background as a function of the read-out threshold, by using a GEANT4 simulation of the Nuclear emulsion, showing that it amounts to about 0.06 per year per kilogram, fully compatible with the design of a 10 kg × year exposure.
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a new fast scanning system for the measurement of large angle tracks in Nuclear Emulsions
Journal of Instrumentation, 2015Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, N Di Marco, G Galati, A Lauria, M C MontesiAbstract:Nuclear Emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, Nuclear Emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use Nuclear Emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.
G. De Lellis - One of the best experts on this subject based on the ideXlab platform.
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a new generation scanning system for the high speed analysis of Nuclear Emulsions
Journal of Instrumentation, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, G Galati, A Lauria, M C Montesi, V TioukovAbstract:The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting Nuclear Emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of Nuclear Emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.
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Intrinsic neutron background of Nuclear Emulsions for directional Dark Matter searches
Astroparticle Physics, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, T Asada, N. D'ambrosio, A. Di Crescenzo, N. Di Marco, M. L. Di Vacri, S. FuruyaAbstract:Recent developments of the Nuclear emulsion technology led to the production of films with nanometric silver halide grains suitable to track low energy Nuclear recoils with submicrometric length. This improvement opens the way to a directional Dark Matter detection, thus providing an innovative and complementary approach to the on-going WIMP searches. An important background source for these searches is represented by neutron-induced Nuclear recoils that can mimic the WIMP signal. In this paper we provide an estimation of the contribution to this background from the intrinsic radioactive contamination of Nuclear Emulsions. We also report the neutron-induced background as a function of the read-out threshold, by using a GEANT4 simulation of the Nuclear emulsion, showing that it amounts to about 0.06 per year per kilogram, fully compatible with the design of a 10 kg × year exposure.
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a new fast scanning system for the measurement of large angle tracks in Nuclear Emulsions
Journal of Instrumentation, 2015Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, N Di Marco, G Galati, A Lauria, M C MontesiAbstract:Nuclear Emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, Nuclear Emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use Nuclear Emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.
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Nuclear Emulsions as a very high resolution detector for directional dark matter search
Journal of Instrumentation, 2014Co-Authors: N Dambrosio, G. De Lellis, Tatsuhiro Naka, A Alexandrov, A Di Crescenzo, N Di Marco, F Pupilli, V Tioukov, C Sirignano, T AsadaAbstract:The use of Nuclear Emulsions in particle physics dates back to the very early stages. They are now used when an extremely high position resolution is required like in the search for short lived particles. The capability to detect Nuclear recoils induced by WIMPs relies on the possibility to detect sub-micrometric trajectories. Recently Nuclear Emulsions with silver grains of 20 nm diameter were developed, opening the way for the reconstruction of nanometric particles. This challenging purpose requires the development of fully automated optical readout systems for a fast scanning of the emulsion films. This is meant for a pre-selection of recoil candidates. Once candidates have been identified, a fine grained X-ray microscope is used to detect the grains making up the tracks. We report here the present results on the current development along this line.
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Hardware performance of a scanning system for high speed analysis of Nuclear Emulsions
Nuclear Instruments and Methods in Physics Research Section A: Accelerators Spectrometers Detectors and Associated Equipment, 2006Co-Authors: L. Arrabito, L Consiglio, M Cozzi, S Buontempo, E. Barbuto, C. Bozza, D. Coppola, J. Damet, N. D'ambrosio, G. De LellisAbstract:The use of Nuclear Emulsions in very large physics experiments is now possible thanks to the recent improvements in the industrial production of Emulsions and to the development of fast automated microscopes. In this paper the hardware performances of the European Scanning System (ESS) are described. The ESS is a very fast automatic system developed for the mass scanning of the Emulsions of the OPERA experiment, which requires microscopes with scanning speeds of about 20 cm^2/h in an emulsion volume of 44 micron thickness.
A Alexandrov - One of the best experts on this subject based on the ideXlab platform.
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a new generation scanning system for the high speed analysis of Nuclear Emulsions
Journal of Instrumentation, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, G Galati, A Lauria, M C Montesi, V TioukovAbstract:The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting Nuclear Emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of Nuclear Emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.
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Intrinsic neutron background of Nuclear Emulsions for directional Dark Matter searches
Astroparticle Physics, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, T Asada, N. D'ambrosio, A. Di Crescenzo, N. Di Marco, M. L. Di Vacri, S. FuruyaAbstract:Recent developments of the Nuclear emulsion technology led to the production of films with nanometric silver halide grains suitable to track low energy Nuclear recoils with submicrometric length. This improvement opens the way to a directional Dark Matter detection, thus providing an innovative and complementary approach to the on-going WIMP searches. An important background source for these searches is represented by neutron-induced Nuclear recoils that can mimic the WIMP signal. In this paper we provide an estimation of the contribution to this background from the intrinsic radioactive contamination of Nuclear Emulsions. We also report the neutron-induced background as a function of the read-out threshold, by using a GEANT4 simulation of the Nuclear emulsion, showing that it amounts to about 0.06 per year per kilogram, fully compatible with the design of a 10 kg × year exposure.
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a new fast scanning system for the measurement of large angle tracks in Nuclear Emulsions
Journal of Instrumentation, 2015Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, N Di Marco, G Galati, A Lauria, M C MontesiAbstract:Nuclear Emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, Nuclear Emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use Nuclear Emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.
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Nuclear Emulsions as a very high resolution detector for directional dark matter search
Journal of Instrumentation, 2014Co-Authors: N Dambrosio, G. De Lellis, Tatsuhiro Naka, A Alexandrov, A Di Crescenzo, N Di Marco, F Pupilli, V Tioukov, C Sirignano, T AsadaAbstract:The use of Nuclear Emulsions in particle physics dates back to the very early stages. They are now used when an extremely high position resolution is required like in the search for short lived particles. The capability to detect Nuclear recoils induced by WIMPs relies on the possibility to detect sub-micrometric trajectories. Recently Nuclear Emulsions with silver grains of 20 nm diameter were developed, opening the way for the reconstruction of nanometric particles. This challenging purpose requires the development of fully automated optical readout systems for a fast scanning of the emulsion films. This is meant for a pre-selection of recoil candidates. Once candidates have been identified, a fine grained X-ray microscope is used to detect the grains making up the tracks. We report here the present results on the current development along this line.
V Tioukov - One of the best experts on this subject based on the ideXlab platform.
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muography with Nuclear Emulsions stromboli and other projects
Annals of Geophysics, 2017Co-Authors: V Tioukov, P. Strolin, L Consiglio, C. Bozza, Giovanni De Lellis, A Sheshukov, M Orazi, R Peluso, Chiara De Sio, S M StellacciAbstract:The muon radiography is a novel imaging technique to probe the volcanoes interior, using the capability of high energy cosmic ray muons to penetrate large thicknesses of rock. In this way it is possible to derive a 2D density map along the muon trajectory of volcanic edifices and deduce information on the variations in the rock density distribution, like those expected from dense lava conduits, or low density magma supply paths. This method is applicable also to study geological objects as glaciers, faults, oil underground reservoirs, engineering constructions, where a density contrast is present. Nuclear Emulsions are well suited to be employed in this context for their excellent angular resolution; they are compact and robust detectors, able to work in harsh environments without need of power supply. On the other side, a long exposure time is required for a reasonable detector surface (~10 m 2 ) in order to collect a sufficient statistics of muons, and a quasi-real time analysis of the emulsion data is rather difficult due to the scanning time needed by the optical microscopes. Such drawback is on the way to be overcome thanks to a recent R&D program on ultra-fast scanning systems. Muon radiography technique, even if limited to the summit part of the volcano edifice, represents an important tool of investigation, at higher spatial resolution, complementary to the conventional geophysics techniques. The first successful result in this field was obtained by a Japanese group that observed in 2007 the conduit structure of Mt. Asama. Since 2010, other interesting volcanoes have been probed with the same method: Stromboli in 2011, Mt. Teide in 2012 and La Palma in 2014. Here we discuss the muon imaging technique reporting the Nuclear emulsion detector design exposed at Stromboli and results of the data analysis.
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a new generation scanning system for the high speed analysis of Nuclear Emulsions
Journal of Instrumentation, 2016Co-Authors: A Alexandrov, G. De Lellis, A Buonaura, L Consiglio, N Dambrosio, A Di Crescenzo, G Galati, A Lauria, M C Montesi, V TioukovAbstract:The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting Nuclear Emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of Nuclear Emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.
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Nuclear Emulsions as a very high resolution detector for directional dark matter search
Journal of Instrumentation, 2014Co-Authors: N Dambrosio, G. De Lellis, Tatsuhiro Naka, A Alexandrov, A Di Crescenzo, N Di Marco, F Pupilli, V Tioukov, C Sirignano, T AsadaAbstract:The use of Nuclear Emulsions in particle physics dates back to the very early stages. They are now used when an extremely high position resolution is required like in the search for short lived particles. The capability to detect Nuclear recoils induced by WIMPs relies on the possibility to detect sub-micrometric trajectories. Recently Nuclear Emulsions with silver grains of 20 nm diameter were developed, opening the way for the reconstruction of nanometric particles. This challenging purpose requires the development of fully automated optical readout systems for a fast scanning of the emulsion films. This is meant for a pre-selection of recoil candidates. Once candidates have been identified, a fine grained X-ray microscope is used to detect the grains making up the tracks. We report here the present results on the current development along this line.
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a novel approach for fast scanning of Nuclear Emulsions with continuous motion of the microscope stage
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2013Co-Authors: A. Aleksandrov, V TioukovAbstract:Abstract Nuclear Emulsions have been used in particle physics experiments for many decades because of their unique spatial resolution. The use of Nuclear Emulsions as precise tracking detectors in large experiments has recently been made possible due to advances in the production of emulsion films and to the development of very fast automatic scanning devices. The present scanning speed of the European Scanning System (ESS), which has been developed within the OPERA Collaboration, is about 20 cm 2 /h. In addition to the scanning of OPERA films, the ESS is used for other applications with ever-growing demands for scanning speed, such as the muon radiography of volcanoes. In order to further increase the scanning speed of the ESS, we are testing a novel approach different from the standard stop-and-go motion of the microscope stage in the horizontal plane. Indeed we perform data acquisition with the stage moving at constant speed, using an objective lens with wide field of view. Unlike the implementation realized in Japan where the movement of objective lens and stage are synchronized to pile up images of the same view in a vertical stack, in this approach only the stage is moving horizontally. Thus images at different depths are not fully overlapped and special care is needed in the reconstruction. This approach can give a substantial increase in the scanning speed, especially for thin emulsion layers and wide field of view. In this paper we demonstrate that, after applying special corrections, the emulsion data quality can be as good as with the standard stop-and-go approach. This technique allows to double the scanning speed of the ESS, bringing it to 40 cm 2 /h without any hardware modification.
