A bstract. From arecentre-analysisoftheavailabledata, Be and B G alactic evolution appears to sho... more A bstract. From arecentre-analysisoftheavailabledata, Be and B G alactic evolution appears to show evidence fora two-slopebehaviourwith respectto O .Theinferred Be/O abundance ratio in halo stars is constant at very low m etallicity (prim ary behaviour)and increasesproportionallytoO /H athigh m etallicity(secondarybehaviour). W e show thatthis can be explained in the fram ework of one single m odel,the ‘superbubble m odel’,in which Li, Beand B areproduced by spallation reactionsinduced by energetic particlesaccelerated outofa m ixture ofsupernova (SN)ejecta and am bientinterstellarm edium inside superbubbles (SBs).Allthe qualitative and quantitative constraints,includingtheenergetics,thevalueofthetransition m etallicity and the Li/Beisotopicratio,aresatised provided thattheenergeticparticleshavea spectrum attened atlow energy (in E )and thatthe proportion oftheSN ejectainsideSBsisoftheorderofafew percent. Thislendssupportto Bykov’sacceleration m echanism insideSBsand to theSB dynam ...
Mini-EUSO is the first mission of the JEM-EUSO program on board the International Space Station. ... more Mini-EUSO is the first mission of the JEM-EUSO program on board the International Space Station. It was launched in 2019 and it is currently located in the Russian section (Zvezda module) of the station and viewing our planet from a nadir-facing UV-transparent window. The instrument is based on the concept of the original JEM-EUSO mission and consists of an optical system employing two Fresnel lenses and a focal surface composed of 36 Multi-Anode Photomultiplier tubes, 64 channels each, for a total of 2304 channels with single photon counting sensitivity and an overall field of view of 44° × 44°. Mini-EUSO can map the night-time Earth in the near UV range (predominantly between 290 nm and 430 nm), with a spatial resolution of about 6.3 km and different temporal resolutions of 2.5 µ, 320 µs and 41 ms. Mini-EUSO observations are extremely important to better assess the potential of a space-based detector in studying Ultra-High Energy Cosmic Rays (UHECRs) such as K-EUSO and POEMMA. In ...
To take up the challenge of understanding the origin of the ultra-high-energy cosmic rays (UHECRs... more To take up the challenge of understanding the origin of the ultra-high-energy cosmic rays (UHECRs), new observational means appear necessary. The JEM-EUSO Collaboration has undertaken to open the space road to UHECR studies. For more than a decade, it has been developing a realistic program to measure the UHECRs from space with unprecedented aperture, together with complementary scientific objectives in a broader multidisciplinary context. Several intermediate missions have already been completed (on the ground: EUSO-TA; under stratospheric ballons: EUSO-Balloon and EUSO-SPB1; in space: TUS, and on-board the ISS: MINI-EUSO), and others are in preparation for flight (EUSO-SPB2), under review (K-EUSO: currently on hold), or proposed for the next decade (POEMMA). We report on the general status of the JEM-EUSO program, underlining that its technology has now reached operational maturity, and is ready for actual cosmic-ray shower detection from above.
Mini-EUSO is part of the JEM-EUSO program and operates on board the International Space Station (... more Mini-EUSO is part of the JEM-EUSO program and operates on board the International Space Station (ISS). It is a UV-telescope with single-photon counting capability looking at nighttime downwards to the Earth through a nadir-facing UV-transparent window. As part of the pre-flight tests, the Mini-EUSO engineering model, a telescope with 1/9 of the original focal surface and a lens of 2.5 cm diameter, has been built and tested. Tests of the Mini-EUSO engineering model have been made in laboratory and in open-sky conditions. Laboratory tests have been performed at the TurLab facility, located at the Physics Department of the University of Turin, equipped with a rotating tank containing different types of materials and light sources. In this way, the configuration for the observation of the Earth from space was emulated, including the Mini-EUSO trigger schemes. In addition to the qualification and calibration tests, the Mini-EUSO engineering model has also been used to evaluate the possib...
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific ... more HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Special Relativity, as introduced by Einstein, is regarded as one of the most important revolutio... more Special Relativity, as introduced by Einstein, is regarded as one of the most important revolutions in the history of physics. Nevertheless, the observation of direct outcomes of this theory on mundane objects is impossible because they can only be witnessed when travelling at relative speeds approaching the light velocity c. These effects are so counterintuitive and contradicting with our daily understanding of space and time that physics students find it hard to learn special relativity beyond mathematical equations and to understand the deep implications of the theory. Although we cannot travel at the speed of light, Virtual Reality (VR) makes it possible to experiment the effects of relativity in a 3D immersive environment (a CAVE: Cave Automatic Virtual Environment). The use of the immersive environment is underpinned by the development of dedicated learning scenarios created through a dialectic between VR-related computational constraints and cognitive constraints that include...
The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) with a large ... more The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) with a large and wide-angle telescope to be mounted on the International Space Station will open up ”particle astronomy” from space. It will characterize Ultra High-Energy Cosmic Rays (UHECR) by detecting fluorescent and Cherenkov photons generated by air showers in the earth’s atmosphere. The JEM-EUSO telescope consists of 3 light-weight optical Fresnel lenses with a diameter of about 2.5 m, 300 k channels of MAPMTs, frontend readout electronics, trigger electronics, and system electronics. An infrared camera and a LIDAR system on-board and a global light system on the ground will also be used to monitor the earth’s atmosphere and to calibrate the telescope instruments.
Context. Recent observations of unexpected structures in the Galactic cosmic ray (GCR) spectrum a... more Context. Recent observations of unexpected structures in the Galactic cosmic ray (GCR) spectrum and composition, as well as growing evidence for episodes of intense dynamical activity in the inner regions of the Galaxy, call for an evaluation of the high-energy particle acceleration associated with such activity and its potential impact on the global GCR phenomenology. Aims. We investigate whether particles accelerated during high-power episodes around the Galactic centre can account for a significant fraction of the observed GCRs, or, conversely, what constraints can be derived regarding their Galactic transport if their contributions are negligible. Methods. Particle transport in the Galaxy is described with a two-zone analytical model. We solved for the contribution of a Galactic centre cosmic-Ray (GCCR) source using Green functions and Bessel expansion, and discussed the required injection power for these GCCRs to influence the global GCR phenomenology at Earth. Results. We find...
The ground array of the Pierre Auger Observatory will consist of 1600 water Cherenkov detectors a... more The ground array of the Pierre Auger Observatory will consist of 1600 water Cherenkov detectors arranged in a triangular grid with a spacing of 1.5 km. Each detector station contains 12 tons of clean water as Cherenkov radiator in a cylindrical volume of 3.6 m diameter and 1.2 m height. The detector walls are lined with tyvec as a diffuse reflector to homogenize the Cherenkov light. The light detection occurs via three photo-multipliers of 20 cm diameter facing downward and arranged symmetrically on the water surface. The performance of the radiator, the reflector and the readout electronics have to be calibrated regularly. Due to the extent of the ground array and the rough terrain all detector stations have to be autonomous and maintenance free. This implies that the calibration method has to be simple and robust. It also has to be cost-effective since it will be implemented 1600 times. The electronics of the surface detector has highand low-gain channels which have to be calibrat...
A bstract. From arecentre-analysisoftheavailabledata, Be and B G alactic evolution appears to sho... more A bstract. From arecentre-analysisoftheavailabledata, Be and B G alactic evolution appears to show evidence fora two-slopebehaviourwith respectto O .Theinferred Be/O abundance ratio in halo stars is constant at very low m etallicity (prim ary behaviour)and increasesproportionallytoO /H athigh m etallicity(secondarybehaviour). W e show thatthis can be explained in the fram ework of one single m odel,the ‘superbubble m odel’,in which Li, Beand B areproduced by spallation reactionsinduced by energetic particlesaccelerated outofa m ixture ofsupernova (SN)ejecta and am bientinterstellarm edium inside superbubbles (SBs).Allthe qualitative and quantitative constraints,includingtheenergetics,thevalueofthetransition m etallicity and the Li/Beisotopicratio,aresatised provided thattheenergeticparticleshavea spectrum attened atlow energy (in E )and thatthe proportion oftheSN ejectainsideSBsisoftheorderofafew percent. Thislendssupportto Bykov’sacceleration m echanism insideSBsand to theSB dynam ...
Mini-EUSO is the first mission of the JEM-EUSO program on board the International Space Station. ... more Mini-EUSO is the first mission of the JEM-EUSO program on board the International Space Station. It was launched in 2019 and it is currently located in the Russian section (Zvezda module) of the station and viewing our planet from a nadir-facing UV-transparent window. The instrument is based on the concept of the original JEM-EUSO mission and consists of an optical system employing two Fresnel lenses and a focal surface composed of 36 Multi-Anode Photomultiplier tubes, 64 channels each, for a total of 2304 channels with single photon counting sensitivity and an overall field of view of 44° × 44°. Mini-EUSO can map the night-time Earth in the near UV range (predominantly between 290 nm and 430 nm), with a spatial resolution of about 6.3 km and different temporal resolutions of 2.5 µ, 320 µs and 41 ms. Mini-EUSO observations are extremely important to better assess the potential of a space-based detector in studying Ultra-High Energy Cosmic Rays (UHECRs) such as K-EUSO and POEMMA. In ...
To take up the challenge of understanding the origin of the ultra-high-energy cosmic rays (UHECRs... more To take up the challenge of understanding the origin of the ultra-high-energy cosmic rays (UHECRs), new observational means appear necessary. The JEM-EUSO Collaboration has undertaken to open the space road to UHECR studies. For more than a decade, it has been developing a realistic program to measure the UHECRs from space with unprecedented aperture, together with complementary scientific objectives in a broader multidisciplinary context. Several intermediate missions have already been completed (on the ground: EUSO-TA; under stratospheric ballons: EUSO-Balloon and EUSO-SPB1; in space: TUS, and on-board the ISS: MINI-EUSO), and others are in preparation for flight (EUSO-SPB2), under review (K-EUSO: currently on hold), or proposed for the next decade (POEMMA). We report on the general status of the JEM-EUSO program, underlining that its technology has now reached operational maturity, and is ready for actual cosmic-ray shower detection from above.
Mini-EUSO is part of the JEM-EUSO program and operates on board the International Space Station (... more Mini-EUSO is part of the JEM-EUSO program and operates on board the International Space Station (ISS). It is a UV-telescope with single-photon counting capability looking at nighttime downwards to the Earth through a nadir-facing UV-transparent window. As part of the pre-flight tests, the Mini-EUSO engineering model, a telescope with 1/9 of the original focal surface and a lens of 2.5 cm diameter, has been built and tested. Tests of the Mini-EUSO engineering model have been made in laboratory and in open-sky conditions. Laboratory tests have been performed at the TurLab facility, located at the Physics Department of the University of Turin, equipped with a rotating tank containing different types of materials and light sources. In this way, the configuration for the observation of the Earth from space was emulated, including the Mini-EUSO trigger schemes. In addition to the qualification and calibration tests, the Mini-EUSO engineering model has also been used to evaluate the possib...
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific ... more HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Special Relativity, as introduced by Einstein, is regarded as one of the most important revolutio... more Special Relativity, as introduced by Einstein, is regarded as one of the most important revolutions in the history of physics. Nevertheless, the observation of direct outcomes of this theory on mundane objects is impossible because they can only be witnessed when travelling at relative speeds approaching the light velocity c. These effects are so counterintuitive and contradicting with our daily understanding of space and time that physics students find it hard to learn special relativity beyond mathematical equations and to understand the deep implications of the theory. Although we cannot travel at the speed of light, Virtual Reality (VR) makes it possible to experiment the effects of relativity in a 3D immersive environment (a CAVE: Cave Automatic Virtual Environment). The use of the immersive environment is underpinned by the development of dedicated learning scenarios created through a dialectic between VR-related computational constraints and cognitive constraints that include...
The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) with a large ... more The Extreme Universe Space Observatory on the Japanese Experiment Module (JEM-EUSO) with a large and wide-angle telescope to be mounted on the International Space Station will open up ”particle astronomy” from space. It will characterize Ultra High-Energy Cosmic Rays (UHECR) by detecting fluorescent and Cherenkov photons generated by air showers in the earth’s atmosphere. The JEM-EUSO telescope consists of 3 light-weight optical Fresnel lenses with a diameter of about 2.5 m, 300 k channels of MAPMTs, frontend readout electronics, trigger electronics, and system electronics. An infrared camera and a LIDAR system on-board and a global light system on the ground will also be used to monitor the earth’s atmosphere and to calibrate the telescope instruments.
Context. Recent observations of unexpected structures in the Galactic cosmic ray (GCR) spectrum a... more Context. Recent observations of unexpected structures in the Galactic cosmic ray (GCR) spectrum and composition, as well as growing evidence for episodes of intense dynamical activity in the inner regions of the Galaxy, call for an evaluation of the high-energy particle acceleration associated with such activity and its potential impact on the global GCR phenomenology. Aims. We investigate whether particles accelerated during high-power episodes around the Galactic centre can account for a significant fraction of the observed GCRs, or, conversely, what constraints can be derived regarding their Galactic transport if their contributions are negligible. Methods. Particle transport in the Galaxy is described with a two-zone analytical model. We solved for the contribution of a Galactic centre cosmic-Ray (GCCR) source using Green functions and Bessel expansion, and discussed the required injection power for these GCCRs to influence the global GCR phenomenology at Earth. Results. We find...
The ground array of the Pierre Auger Observatory will consist of 1600 water Cherenkov detectors a... more The ground array of the Pierre Auger Observatory will consist of 1600 water Cherenkov detectors arranged in a triangular grid with a spacing of 1.5 km. Each detector station contains 12 tons of clean water as Cherenkov radiator in a cylindrical volume of 3.6 m diameter and 1.2 m height. The detector walls are lined with tyvec as a diffuse reflector to homogenize the Cherenkov light. The light detection occurs via three photo-multipliers of 20 cm diameter facing downward and arranged symmetrically on the water surface. The performance of the radiator, the reflector and the readout electronics have to be calibrated regularly. Due to the extent of the ground array and the rough terrain all detector stations have to be autonomous and maintenance free. This implies that the calibration method has to be simple and robust. It also has to be cost-effective since it will be implemented 1600 times. The electronics of the surface detector has highand low-gain channels which have to be calibrat...
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