1,721,257 research outputs found
Polar balloon flights with a scaled version of CALET
No full textThe CALorimetric Electron Telescope (CALET) is a candidate instrument to be installed on the JEM-EF facility on the International Space Station (ISS). It is optimized for the search of nearby sources of acceleration of cosmic ray electrons in the TeV energy range. In addition, the combination of a large collection power and long observation time allows for precision studies of the elemental composition of VHE nuclei and of their spectral features. Earlier versions of the instrument have been flown on balloons in Japan and Antarctica; a 1/64 scaled version (bCALET-1) was launched from Sanriku in 2006 and a 4 times larger payload is in preparation. In this paper, a 1/4 version of CALET is proposed as a candidate balloon payload for Arctic flights
New calorimeters for space experiments: physics requirements and technological challenges
No full textDirect measurements of charged cosmic radiation with instruments in Low Earth Orbit (LEO), or flying on balloons above the atmosphere, require the identification of the incident particle, the measurement of its energy and possibly the determination of its sign-of-charge. The latter information can be provided by a magnetic spectrometer together with a measurement of momentum. However, magnetic deflection in space experiments is at present limited to values of the Maximum Detectable Rigidity (MDR) hardly exceeding a few TV. Advanced calorimetric techniques are, at present, the only way to measure charged and neutral radiation at higher energies in the multi-TeV range. Despite their mass limitation, calorimeters may achieve a large geometric factor and provide an adequate proton background rejection factor, taking advantage of a fine granularity and imaging capabilities. In this lecture, after a brief introduction on electromagnetic and hadronic calorimetry, an innovative approach to the design of a space-borne, large acceptance, homogeneous calorimeter for the detection of high energy cosmic rays will be described
Performance of the Charge Detectors of CALET with relativistic ions
No full textCALET is an all-calorimetric electron telescope in preparation for a launch to the International Space Station (ISS), where it will be installed on the Exposure Facility of the Japanese Experiment Module (JEM-EF). With observations over a period of five years, CALET will be able to unveil the presence of possible nearby sources of high energy electrons and search for signatures of dark matter. The instrument includes a two-layered Charge Detector (CHD) module of scintillator paddles designed to identify - via a measurement of their electric charge - individual nuclear species from proton to iron and to detect trans-iron elements. Complementary charge information is provided by the Imaging Calorimeter (IMC)
CALET: A calorimeter-based orbital observatory for High Energy Astroparticle Physics
No full textCALET is an advanced experiment that will be installed on the Exposure Facility of the Japanese Experiment Module (JEM-EF) on the International Space Station (ISS) with a launch window in 2014. The instrument consists of three main sub-systems: a charge module using plastic scintillators to identify the charge of the particle, a thin imaging calorimeter (3X0) with tungsten plates interleaving scintillating fiber planes, and a thick calorimeter (27X0) composed of lead tungstate logs. It has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma-rays. The charge module will be able to identify cosmic nuclei from H through Fe as well as trans-Fe elements at least up to Zr (Z=40). With extended observations, over a period of 5 years, CALET will be able to unveil the presence of possible nearby sources of high energy electrons, study the details of particle propagation in the galaxy and search for signatures of dark matter.
In this paper, we will review the main features of the CALET instrument and the present status of the mission
The CALorimetric Electron Telescope (CALET) on the International Space Station
No full textThe CALorimetric Electron Telescope (CALET) space experiment, developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission installed on the international Space Station (ISS). The primary goals of the CALET mission include investigating on the possible presence of nearby sources of high-energy electrons, studying the details of galactic particle propagation and searching for dark matter signatures. During a two-year mission, extendable to five years, CALET can measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei with Z = 1 to 40 up to 1,000 TeV. The instrument consists of two layers of segmented plastic scintillators for cosmic-ray charge identification (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. The instrument was launched on August 19, 2015 to the ISS with the H-II Transfer Vehicle 5 (HTV-5) and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) on August 25. Since the start of operations in mid-October, 2015, a continuous observation has been going on mainly by triggering high energy (>10 GeV) showers without any major interruption. The number of triggered events above 10 GeV is nearly 20 million per month. By using the data obtained during the first two years, we give a summary of CALET observations: (1) Electron + Positron energy spectrum, (2) Proton and Nuclei spectrum, (3) Gamma-ray observation, with results of the performance study on orbit. We also present the results of observations of the electromagnetic counterparts to LIGO-VIRGO gravitational wave events and high-energy counterparts to GRB events measured with the CALET Gamma-ray Burst Monitor (CGBM). (C) 2019 COSPAR. Published by Elsevier Ltd. All rights reserved
CALET on the ISS: A high energy astroparticle physics experiment
Get PDFCALET is a space mission of the Japanese Aerospace Agency (JAXA) in collaboration with the Italian Space Agency (ASI) and NASA. The CALET instrument (CALorimetric Electron Telescope) is planned for a long exposure on the JEM-EF, an external platform of the Japanese Experiment Module KIBO, aboard the International Space Station (ISS). The main science objectives include high precision measurements of the inclusive electron (+positron) spectrum below 1 TeV and the exploration of the energy region above 1 TeV, where the shape of the high end of the spectrum might reveal the presence of nearby sources of acceleration. With an excellent energy resolution and low background contamination CALET will search for possible spectral signatures of dark matter with both electrons and gamma rays. It will also measure the high energy spectra and relative abundance of cosmic nuclei from proton to iron and detect trans-iron elements up to Z ∼ 40. With a large exposure and high energy resolution, CALET will be able to verify and complement the observations of CREAM, PAMELA and AMS-02 on a possible deviation from a pure power-law of proton and He spectra in the region of a few hundred GeV and to extend the study to the multi-TeV region. CALET will also contribute to clarify the present experimental picture on the energy dependence of the boron/carbon ratio, below and above 1 TeV/n, thereby providing valuable information on cosmic-ray propagation in the galaxy. Gamma-ray transients will be studied with a dedicated Gamma-ray Burst Monitor (GBM)
High-energy astroparticle physics with CALET
No full textThe CALorimetric Electron Telescope (CALET) will be installed on the Exposure
Facility of the Japanese Experiment Module (JEM-EF) on the International Space Station (ISS)
in 2014 where it will measure the cosmic-ray fluxes for five years. Its main scientific goals are to
search for dark matter, investigate the mechanism of cosmic-ray acceleration and propagation in
the Galaxy and discover possible astrophysical sources of high-energy electrons nearby the Earth.
The instrument, under construction, consists of two layers of segmented plastic scintillators for
the cosmic-ray charge identification (CHD), a 3 X0-thick tungsten-scintillating fiber imaging
calorimeter (IMC) and a 27 X0-thick lead-tungstate calorimeter (TASC). The CHD can provide
single-element separation in the interval of atomic number Z from 1 to 40, while IMC and TASC
can measure the energy of cosmic-ray particles with excellent resolution in the range from few
GeV up to several hundreds of TeV. Moreover, IMC and TASC provide the longitudinal and
lateral development of the shower, a key issue for good electron/hadron discrimination. In this
paper, we will review the status of the mission, the instrument configuration and its expected
performance, and the CALET capability to measure the different components of the cosmic
radiation
Landslide susceptibility mapping in lunar south pole region
No full textThe study addresses a challenge in planetary exploration, focusing on landslide susceptibility on the Lunar South Pole Region (LSPR), fundamental for future lunar missions. Features like permanently shadowed regions and water ice deposits attract scientific attention but issues related to rugged terrain and dynamic geological processes must also to be considered. The photointerpretation of data from Lunar Reconnaissance Orbiter (LRO) mission, allowed to create a landslides inventory map. The Frequency Ratio (FR) model was applied to generate a landslide susceptibility map (LSM). Geological and morphological factors were derived from existing maps and LRO data. Peak Ground Acceleration (PGA) variation and epicentral distance were used to define seismic hazard zones. LSM accuracy was evaluated using the Area Under the Curve (AUC) method. The study allows to identify geological formations susceptible to seismic-induced landslides, aiding site selection for future lunar missions. This interdisciplinary approach integrates planetary geology, remote sensing, and GIS software and it contributes to lunar exploration and exploitation for scientific and resource purposes allowing to optimize the Moon involvement in solar system exploration
CALET on the International Space Station: new direct measurements of cosmic-ray iron and nickel
Get PDFThe Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray over a wide energy interval. Approximately 20 million triggered events per month are recorded with energies > 10 GeV. The instrument identifies the charge of individual elements up to nickel and beyond and, thanks to a homogeneous lead-tungstate calorimeter, it measures the energy of cosmic-ray nuclei providing a direct measurement of their spectra. Iron and nickel spectra are a low background measurement with negligible contamination from spallation of higher mass elements. Iron and nickel nuclei play a key role in
understanding the acceleration and propagation mechanisms of charged particles in our Galaxy. In this contribution a direct measurement of iron and nickel spectra, based on more than five years of data, are presented in the energy range from 10 GeV/n to 2 TeV/n and from 8.8 GeV/n to 240 GeV/n, respectively. The spectra are compatible within the errors with a single power law in the energy region from 50 GeV/n to 2 TeV/n and from 20 GeV/n to 240 GeV/n, respectively. Systematic
uncertainties are detailed and the nickel to iron flux ratio is presented. This unprecedented measurement confirms that both elements have very similar fluxes in shape and energy dependence, suggesting that their origin, acceleration, and propagation might be explained invoking an identical mechanism in the energy range explored so far
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