This analysis documents the process and results of reliability determination of the PhotoMultiplier Tube (PMT) components of the JEM-EUSO telescope under the different radiation sources, UV ...radiation, Total Ionizing Doses (TIDs), and Single Event Transients. In terms of UV Ionization, the transmittance of the glass of the PMTs during the 5-year duration of the mission is greater than 99.98%, thereby ensuring the desired 20% value for quantum efficiency. Of the 4932 PMTs covering the focal surface of the telescope, we estimate that of order 7 may fail due to TID and about 16 may fail due to SET. Therefore, it can be concluded that around 99% of the PMTs will complete their operation without failure, ensuring the success of the mission as far as TIDs and SETs radiation is concerned. PMTs suffer basically due to high brightness effects, reducing the transmittance of the crystal window. However, the result of this study, taking into account the values produced by the model based on the TID, as well as the darkening of the glass, show similar values in terms of degradation. Therefore, as a preliminary result, it is possible to conclude that the TID model proposed here for PMTs can be “validated”.
•Current methods and Space standards for the reliability analysis were evaluated.•New techniques to assess space radiation impact on electronic components are proposed.•Techniques suitable for reliability analysis of PMTs devoted to space applications.•Techniques developed can be used to enhance current reliability analysis standards.
The search for correlations between secondary cosmic ray detection rates and seismic effects has long been a subject of investigation motivated by the hope of identifying a new precursor type that ...could feed a global early warning system against earthquakes. Here we show for the first time that the average variation of the cosmic ray detection rates correlates with the global seismic activity to be observed with a time lag of approximately two weeks, and that the significance of the effect varies with a periodicity resembling the undecenal solar cycle, with a shift in phase of around three years, exceeding 6 σ at local maxima. The precursor characteristics of the observed correlations point to a pioneer perspective of an early warning system against earthquakes.
Variations of secondary cosmic ray detection rates are periodically correlated with future global earthquake magnitude sum.
•The local changes of the cosmic ray flux correlate with the global seismic activity.•The cosmic signal correlates with the future seismic activity.•The effect lasts a few years and occurs with periodicity similar to the solar cycle.
JEM-EUSO (Extreme Universe Space Observatory on Japanese Experiment Module) is an advanced observatory that will be on-board the International Space Station (ISS) and use the Earth׳s atmosphere as a ...huge calorimeter detector. However, the atmospheric clouds introduce uncertainties in the signals measured by JEM-EUSO. Therefore, it is extremely important to know the atmospheric conditions and properties of the clouds in the Field of View (FoV) of the telescope. The Atmospheric Monitoring System (AMS) of JEM-EUSO includes a lidar and an infrared imaging system, IR-Camera, aimed to detect the presence of clouds and to obtain the cloud coverage and cloud top altitude during the observations of the JEM-EUSO main telescope. To define the road-map for the design of the electronics, the detector has been tested extensively with a first prototype. The actual design of the IR-Camera, the test of the prototype, and the outcome of this characterization are presented in this paper.
► A new parameter,
S
b, is proposed for composition studies in cosmic ray surface arrays. ► The discrimination capability (
η) of
S
b between proton and iron maximizes for
b
∼
3. ► If muon ...contribution is enhanced, optimal
b is still 3 and
η increases. ► A major advantage is that
S
3 is almost independent on zenith angle. ► Composition accuracy using
S
3 is of the same order than that from
X
max.
A new family of parameters intended for composition studies in cosmic ray surface array detectors is proposed. The application of this technique to different array layout designs has been analyzed. The parameters make exclusive use of surface data combining the information from the total signal at each triggered detector and the array geometry. They are sensitive to the combined effects of the different muon and electromagnetic components on the lateral distribution function of proton and iron initiated showers at any given primary energy. Analytical and numerical studies have been performed in order to assess the reliability, stability and optimization of these parameters. Experimental uncertainties, the underestimation of the muon component in the shower simulation codes, intrinsic fluctuations and reconstruction errors are considered and discussed in a quantitative way. The potential discrimination power of these parameters, under realistic experimental conditions, is compared on a simplified, albeit quantitative way, with that expected from other surface and fluorescence estimators.
An Atmospheric Monitoring System (AMS) is a mandatory and key device of a space-based mission which aims to detect Ultra-High Energy Cosmic Rays (UHECR) and Extremely-High Energy Cosmic Rays (EHECR) ...from Space. JEM-EUSO has a dedicated atmospheric monitoring system that plays a fundamental role in our understanding of the atmospheric conditions in the Field of View (FoV) of the telescope. Our AMS consists of a very challenging space infrared camera and a LIDAR device, that are being fully designed with space qualification to fulfil the scientific requirements of this space mission. The AMS will provide information of the cloud cover in the FoV of JEM-EUSO, as well as measurements of the cloud top altitudes with an accuracy of 500 m and the optical depth profile of the atmosphere transmittance in the direction of each air shower with an accuracy of 0.15 degree and a resolution of 500 m. This will ensure that the energy of the primary UHECR and the depth of maximum development of the EAS (Extensive Air Shower) are measured with an accuracy better than 30% primary energy and 120 g/cm2 depth of maximum development for EAS occurring either in clear sky or with the EAS depth of maximum development above optically thick cloud layers. Moreover a very novel radiometric retrieval technique considering the LIDAR shots as calibration points, that seems to be the most promising retrieval algorithm is under development to infer the Cloud Top Height (CTH) of all kind of clouds, thick and thin clouds in the FoV of the JEM-EUSO space telescope.
The origin of cosmic rays have remained a mistery for more than a century. JEM-EUSO is a pioneer space-based telescope that will be located at the International Space Station (ISS) and its aim is to ...detect Ultra High Energy Cosmic Rays (UHECR) and Extremely High Energy Cosmic Rays (EHECR) by observing the atmosphere. Unlike ground-based telescopes, JEM-EUSO will observe from upwards, and therefore, for a properly UHECR reconstruction under cloudy conditions, a key element of JEM-EUSO is an Atmospheric Monitoring System (AMS). This AMS consists of a space qualified bi-spectral Infrared Camera, that will provide the cloud coverage and cloud top height in the JEM-EUSO Field of View (FoV) and a LIDAR, that will measure the atmospheric optical depth in the direction it has been shot. In this paper we will explain the effects of clouds for the determination of the UHECR arrival direction. Moreover, since the cloud top height retrieval is crucial to analyze the UHECR and EHECR events under cloudy conditions, the retrieval algorithm that fulfills the technical requierements of the Infrared Camera of JEM-EUSO to reconstruct the cloud top height is presently reported.
JEM-EUSO is a space observatory that will be located on-board the Japanese Experiment Module at the International Space Station. It will observe Extensive Air Showers (EAS) induced by ultra-high ...energy cosmic rays using the Earth's atmosphere as detector. In addition to clear sky observations, EAS are also observable in cloudy conditions if a sufficiently large part of the EAS development occurs above the cloud. The atmospheric monitoring system plays a fundamental role in our understanding of the atmospheric conditions in the field of view of the telescope.
INTRODUCTIONIt has been observed in recent years that levels of such molecules as calcitonin gene-related peptide (CGRP) and, to a lesser extent, the pituitary adenylate cyclase-activating peptide ...are elevated during migraine attacks and in chronic migraine, both in the cerebrospinal fluid and in the serum. Pharmacological reduction of these proteins is clinically significant, with an improvement in patients' migraines. It therefore seems logical that one of the main lines of migraine research should be based on the role of CGRP in the pathophysiology of this entity.DEVELOPMENTThe Spanish Society of Neurology's Headache Study Group decided to draft this document in order to address the evidence on such important issues as the role of CGRP in the pathophysiology of migraine and the mechanism of action of monoclonal antibodies and gepants; and to critically analyse the results of different studies and the profile of patients eligible for treatment with monoclonal antibodies, and the impact in terms of pharmacoeconomics.CONCLUSIONSThe clinical development of gepants, which are CGRP antagonists, for the acute treatment of migraine attacks, and CGRP ligand and receptor monoclonal antibodies offer promising results for these patients.
JEM-EUSO, the Extreme Universe Space Observatory (EUSO) on-board the Japanese Experiment Module (JEM) at the International Space Station, is a space-based observatory for Ultra High Energy Cosmic ...Rays (UHECR) which uses the atmosphere as a huge calorimeter. Therefore, an accurate monitoring of the atmosphere in cloudy conditions is important to properly reconstruct the UHECR events observed by the JEM-EUSO telescope. In this work we study the impact of the presence of clouds on the UV signal received by JEM-EUSO from which UHECR events will be reconstructed, and investigate the JEM-EUSO trigger efficiency in cloudy conditions as well.
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