THE FOCAL SURFACE OF THE EUSO TELESCOPE

2005 ◽  
Vol 20 (29) ◽  
pp. 6890-6893 ◽  
Author(s):  
◽  
YOSHIYA KAWASAKI ◽  
M. BERTAINA ◽  
T. EBISUZAKI ◽  
F. KAJINO ◽  
...  
Keyword(s):  
Heat Dissipation ◽  
Detection Efficiency ◽  
Space Station ◽  
Wavelength Region ◽  
High Energy ◽  
Space Mission ◽  
Night Time ◽  
Focal Surface ◽  
Near Ultraviolet ◽  
Surface Detector

The Extreme Universe Space Observatory (EUSO) is a space mission to study extremely high-energy cosmic rays. The EUSO instrument is a wide-angle refractive telescope in near-ultraviolet wavelength region to observe time-resolved atmospheric fluorescence images of the extensive air showers from the International Space Station. The Focal surface is an aspherical curved surface, and its area amounts to about 4.5 m2. The focal surface detector is designed as a mosaic of multianode photomultipliers (MAPMT) for the single photoelectron counting capability. The strongest requirement for the focal surface detector is the maximization of the photon detection efficiency together with the uniformity over the focal surface. We have developed a new type of MAPMT. It is modified from the ordinary one and has a grid between the photocathode and the first dynode to electrostatically demagnify the photoelectron image on the dynode. We are also developing the HV supply system for a great number of MAPMTs. EUSO experiments the day-time and night-time every 90 minutes. The heat flow must be considered to stabilize the PMT characteristics, in parallel with the heat dissipation of the electronics attached on the focal surface supporting structure.

scholarly journals THE JEM-EUSO MISSION: OBSERVATION OF ULTRA-HIGH ENERGY COSMIC RAYS FROM SPACE

2013 ◽  
Vol 23 ◽  
pp. 329-334
Author(s):  
◽  
M. RICCI
Keyword(s):  
Cosmic Rays ◽  
Space Station ◽  
Infrared Camera ◽  
High Energy ◽  
Ultra High Energy ◽  
Significant Information ◽  
Full Field ◽  
High Energy Cosmic Rays ◽  
Focal Surface ◽  
Fresnel Lenses

The Extreme Universe Space Observatory on Japanese Experiment Module (JEM-EUSO) is a science mission planned to be launched in 2017 to the International Space Station (ISS) to investigate the nature and origin of Ultra High Energy Cosmic Rays (UHECR) beyond energy 3 × 1019 eV. JEM-EUSO is a wide-angle telescope (60 degrees full field of view) and consists of a high-transmittance Fresnel lenses 2.5 m in diameter, an advanced photo-sensitive detector at the focal surface and a suitable electronics. An infrared camera and a LIDAR system will also be used to monitor the Earth's atmosphere and provide significant information on cloud coverage. The present status of advancement of the mission is reported.

Simultaneous detection of lightning flashes by MMIA-ASIM and Colombia Lightning Mapping Array

2020 ◽  
Author(s):  
Jesús Alberto López ◽  
Joan Montanyà ◽  
Oscar van der Velde ◽  
Ferran Fabró ◽  
Javier Navarro ◽  
...  
Keyword(s):  
Multispectral Imaging ◽  
Gamma Ray ◽  
Detection Efficiency ◽  
Simultaneous Detection ◽  
Space Station ◽  
Optical Emission ◽  
High Energy ◽  
Tropical Region ◽  
Mapping Array ◽  
Lightning Leader

<p>Since April 2018, the Atmosphere-Space Interactions Monitor (ASIM) has been in operation on board the International Space Station (ISS). ASIM is composed of the Modular X-and Gamma Ray Sensor (MXGS) as well as a multispectral and high resolution array of photometers and cameras, called the Modular Multispectral Imaging Array (MMIA). These instruments allow us to investigate Terrestrial Gamma-Flashes, Transient Luminous Events and their interactions with thunderstorms and lightning flashes.</p><p>The Colombia Lightning Mapping Array (COL-LMA), operational since 2017, is the first VHF range network installed and working in a tropical region, and can contribute to the electrical understanding of thunderstorms and lightning leader processes associated with high energy phenomena in the upper atmosphere.</p><p>This work employs data from the MMIA array to investigate optical emission patterns at different bands (337 nm, 180-230 nm and 777.4 nm) caused by lightning leader development and cloud-to-ground flashes, derived from the COL-LMA and LINET network respectively. All cases are also correlated with optical observation from the Lightning Imaging Sensor (LIS) on board the ISS, and the Geostationary Lightning Mapper sensor on the GOES-R satellite.</p><p>The region of study is defined by the high detection-efficiency area of the COL-LMA around the Magdalena river valley. MMIA-ASIM information since July 2019 corresponding to passes over this tropical region has been analysed.</p>

scholarly journals Silicon Photomultipliers: Technology Optimizations for Ultraviolet, Visible and Near-Infrared Range

Instruments ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 15 ◽  
Author(s):  
Fabio Acerbi ◽  
Giovanni Paternoster ◽  
Massimo Capasso ◽  
Marco Marcante ◽  
Alberto Mazzi ◽  
...  
Keyword(s):  
Near Infrared ◽  
Detection Efficiency ◽  
Single Photon ◽  
High Energy ◽  
Infrared Light ◽  
Infrared Range ◽  
Silicon Photomultipliers ◽  
Deep Trench ◽  
Near Ultraviolet ◽  
Physics Experiments

Silicon photomultipliers (SiPMs) are single-photon sensitive solid-state detectors that are becoming popular for several applications, thanks to massive performance improvements over the last years. Starting as a replacement for the photomultiplier tube (PMT), they are now used in medical applications, big high-energy physics experiments, nuclear physics experiments, spectroscopy, biology and light detection and ranging (LIDAR) applications. Due to different requirements in terms of detection efficiency, noise, etc., several optimizations have been introduced by the manufacturers; for example, spectral sensitivity has been optimized for visible light, near ultraviolet, vacuum ultraviolet, and near infrared light. Each one of them require specific processes and structural optimization. We present in this paper recent improvements in SiPM performance, owing to a higher cell fill-factor, lower noise, improved silicon materials, and deep trench isolation. We describe issues related to the characterization of analog SiPM, particularly due to the different sources of correlated noise, which have to be distinguished from each other and from the primary pulses. We also describe particular analyses and optimizations conducted for specific applications like the readout of liquid noble gas scintillators, requiring these detectors to operate at cryogenic temperatures.

scholarly journals Results from the first missions of the JEM-EUSO program

2019 ◽  
Vol 210 ◽  
pp. 05009 ◽  
Author(s):  
Mario Bertaina
Keyword(s):  
Cosmic Rays ◽  
Space Station ◽  
High Energy ◽  
Space Mission ◽  
Wide Field ◽  
Fluorescence Detector ◽  
Telescope Array ◽  
High Energy Cosmic Rays ◽  
Trigger Mode ◽  
Uv Photons

The origin and nature of Ultra-High Energy Cosmic Rays (UHECRs) remain unsolved in contemporary astroparticle physics. To give an answer to these questions is rather challenging because of the extremely low flux of a few per km2 per century at extreme energies such as E > 5 × 1019 eV. The objective of the JEM-EUSO program, Extreme Universe Space Observatory, is the realization of a space mission devoted to scientific research of cosmic rays of highest energies. Its super-wide-field telescope will look down from space onto the night sky to detect UV photons emitted from air showers generated by UHECRs in the atmosphere. The JEM-EUSO program includes different missions using fluorescence detectors to make a proof-of-principle of the UHECR observation from space and to raise the technological level of the instrumentation to be employed in a space mission. EUSO-TA, installed at the Telescope Array site in Utah in 2013, is in operation. It has already detected 9 UHECRs in coincidence with Telescope Array fluorescence detector at Black Rock Mesa. EUSO-Balloon flew on board a stratospheric balloon in August 2014. It measured the UV intensity on forests, lakesandthecityofTimminsaswellasprovedtheobservationofUHECR-likeeventsbyshootinglasertracks. EUSO-SPB was launched on board a super pressure balloon on April 25th and flew for 12 days. It proved the functionality of all the subsystems of the telescope on a typical duration of a balloon flight; observed the UV emission on oceans and has a self-trigger system to observe UHECRs with energy E > 3×1018 eV. TUS, the Russian mission on board the Lomonosov satellite in orbit since April 28th 2016, is now included in the JEMEUSO program and has detected so far in the UHECR trigger-mode a few interesting signals. Mini-EUSO is in its final phase of integration in Italy, where several performance tests are being held. Mini-EUSO will be installed inside the International Space Station (ISS) in 2019. The main results obtained so far by such missions are summarized and put in prospect of future space detectors such as K-EUSO and POEMMA.

An imaging system for EAS optical emission

1968 ◽  
Vol 46 (10) ◽  
pp. S266-S269 ◽  
Author(s):  
A. N. Bunner ◽  
K. Greisen ◽  
P. B. Landecker
Keyword(s):  
Imaging System ◽  
Wavelength Region ◽  
Optical Emission ◽  
Cosmic Ray ◽  
Fresnel Lens ◽  
High Energy ◽  
Ultra High Energy ◽  
Air Showers ◽  
Cornell University ◽  
Focal Surface

The Cornell University Cosmic Ray Group is pursuing an experimental attack on the problem of detecting and analyzing ultra-high-energy air showers by the optical emission m the atmosphere. A technique has been developed to record pulses of light from a sequence of adjacent positions in the night sky, by imaging a sector of the sky onto a mosaic of photomultiplier tubes nested in the focal surface of a large Fresnel lens. Sixteen such lens units are then necessary to view a full 2π steradians. It is shown that, in the wavelength region 3 400 to 4 500 Å, Cerenkov radiation dominates the first 23° from the point of appearance of the shower, while nitrogen fluorescence allows tracking of the shower beyond 23°.

Analysis of a New Hybrid Water-Phase Change Material Heat Sink for Low Concentrated Photovoltaic Systems

2017 ◽  
Author(s):  
Mohamed Emam ◽  
Ali Radwan ◽  
Mahmoud Ahmed
Keyword(s):  
Phase Change ◽  
Phase Change Material ◽  
Water Flow ◽  
Heat Sink ◽  
Heat Dissipation ◽  
Water System ◽  
High Energy ◽  
Heat Extraction ◽  
Night Time ◽  
Change Material

Concentrated photovoltaic (CPV) integrated with phase-change material (CPV-PCM) system is considered as a single module to reduce the CPV temperature rise and achieve higher solar conversion efficiency. For low concentration ratios (CRs), up to 20, a larger PCM thickness is needed to absorb much more heat and prolong the thermal regulation time of CPV systems. As a result, the heat absorbed in the PCM is not released efficiently to the ambient during the night time. Therefore, active heat dissipation from the CPV-PCM system is required during that time to attain full transition to solid state at the starting of each period of insolation. Thus, a hybrid CPV-PCM water system including various designs of the PCM heat sink is proposed. Such system provides a high-energy storage density during the daytime and enhances the heat extraction from PCM during the night time. To predict the thermal and electrical performance of the hybrid CPV-PCM water system, a comprehensive 2-D model for CPV layers integrated with both PCM, and water flow is developed. The model couples thermal models for CPV layers and thermo-fluid model that considers the phase-change phenomenon and water flow. Numerical simulations of the developed models are performed to determine the instantaneous liquid-solid interface evolution and the transient temperature distribution within the hybrid CPV-PCM water system. Results indicate that the hybrid CPV-PCM water system achieves a significant reduction in the CPV temperature during the daytime and improves the heat dissipation from PCM during the night time.

scholarly journals Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

2019 ◽  
Vol 209 ◽  
pp. 01007
Author(s):  
Francesco Nozzoli
Keyword(s):  
Electron Flux ◽  
Space Station ◽  
Cosmic Ray ◽  
High Energy ◽  
Precision Measurements ◽  
High Energy Electrons ◽  
Electrons And Positrons ◽  
Positron Flux ◽  
Rigidity Dependence ◽  
Alpha Magnetic Spectrometer

Precision measurements by AMS of the fluxes of cosmic ray positrons, electrons, antiprotons, protons as well as their rations reveal several unexpected and intriguing features. The presented measurements extend the energy range of the previous observations with much increased precision. The new results show that the behavior of positron flux at around 300 GeV is consistent with a new source that produce equal amount of high energy electrons and positrons. In addition, in the absolute rigidity range 60–500 GV, the antiproton, proton, and positron fluxes are found to have nearly identical rigidity dependence and the electron flux exhibits different rigidity dependence.

scholarly journals Study of the 232Th(n,f) Cross section at NCSR ‘Demokritos’ using Micromegas Detectors

2020 ◽  
Vol 27 ◽  
pp. 106
Author(s):  
Sotirios Chasapoglou ◽  
A. Tsantiri ◽  
A. Kalamara ◽  
M. Kokkoris ◽  
V. Michalopoulou ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Nuclear Reactions ◽  
Detection Efficiency ◽  
High Energy ◽  
Tandem Accelerator ◽  
Line Detector ◽  
Accelerator Driven Systems ◽  
The Masses

The accurate knowledge of neutron-induced fission cross sections in actinides, is of great importance when it comes to the design of fast nuclear reactors, as well as accelerator driven systems. Specifically for the 232Th(n,f) case, the existing experimental datasets are quite discrepant in both the low and high energy MeV regions, thus leading to poor evaluations, a fact that in turn implies the need for more accurate measurements.In the present work, the total cross section of the 232Th(n,f) reaction has been measured relative to the 235U(n,f) and 238U(n,f) ones, at incident energies of 7.2, 8.4, 9.9 MeV and 14.8, 16.5, 17.8 MeV utilizing the 2H(d,n) and 3H(d,n) reactions respectively, which generally yield quasi-monoenergetic neutron beams. The experiments were performed at the 5.5 MV Tandem accelerator laboratory of N.C.S.R. “Demokritos”, using a Micromegas detector assembly and an ultra thin ThO2 target, especially prepared for fission measurements at n_ToF, CERN during its first phase of operations, using the painting technique. The masses of all actinide samples were determined via α-spectroscopy. The produced fission yields along with the results obtained from activation foils were studied in parallel, using both the NeusDesc [1] and MCNP5 [2] codes, taking into consideration competing nuclear reactions (e.g. deuteron break up), along with neutron elastic and inelastic scattering with the beam line, detector housing and experimental hall materials. Since the 232Th(n,f) reaction has a relatively low energy threshold and can thus be affected by parasitic neutrons originating from a variety of sources, the thorough characterization of the neutron flux impinging on the targets is a prerequisite for accurate cross-section measurements, especially in the absence of time-of-flight capabilities. Additional Monte-Carlo simulations were also performed coupling both GEF [3] and FLUKA [4] codes for the determination of the detection efficiency.

scholarly journals Charged projectile spectrometry using solid-state nuclear track detector of the PM-355 type

Nukleonika ◽  
2015 ◽  
Vol 60 (3) ◽  
pp. 591-596 ◽  
Author(s):  
Aneta Malinowska ◽  
Marian Jaskóła ◽  
Andrzej Korman ◽  
Adam Szydłowski ◽  
Karol Malinowski ◽  
...  
Keyword(s):  
Solid State ◽  
Detection Efficiency ◽  
Radiation Detector ◽  
High Energy ◽  
High Energy Resolution ◽  
Projectile Energy ◽  
Scanning System ◽  
Nuclear Track Detector ◽  
Temperature Plasma ◽  
Wide Range

Abstract To use effectively any radiation detector in high-temperature plasma experiments, it must have a lot of benefits and fulfill a number of requirements. The most important are: a high energy resolution, linearity over a wide range of recorded particle energy, high detection efficiency for these particles, a long lifetime and resistance to harsh conditions existing in plasma experiments and so on. Solid-state nuclear track detectors have been used in our laboratory in plasma experiments for many years, but recently we have made an attempt to use these detectors in spectroscopic measurements performed on some plasma facilities. This paper presents a method that we used to elaborate etched track diameters to evaluate the incident projectile energy magnitude. The method is based on the data obtained from a semiautomatic track scanning system that selects tracks according to two parameters, track diameter and its mean gray level.

Sign in / Sign up

Export Citation Format

Share Document