8,688 research outputs found

    EUSO-SPB1 mission and science

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    International audienceThe Extreme Universe Space Observatory on a Super Pressure Balloon 1 (EUSO-SPB1) was launched in 2017 April from Wanaka, New Zealand. The plan of this mission of opportunity on a NASA super pressure balloon test flight was to circle the southern hemisphere. The primary scientific goal was to make the first observations of ultra-high-energy cosmic-ray extensive air showers (EASs) by looking down on the atmosphere with an ultraviolet (UV) fluorescence telescope from suborbital altitude (33 km). After 12 days and 4 h aloft, the flight was terminated prematurely in the Pacific Ocean. Before the flight, the instrument was tested extensively in the West Desert of Utah, USA, with UV point sources and lasers. The test results indicated that the instrument had sensitivity to EASs of ⪆3 EeV. Simulations of the telescope system, telescope on time, and realized flight trajectory predicted an observation of about 1 event assuming clear sky conditions. The effects of high clouds were estimated to reduce this value by approximately a factor of 2. A manual search and a machine-learning-based search did not find any EAS signals in these data. Here we review the EUSO-SPB1 instrument and flight and the EAS search

    EUSO-Offline: A comprehensive simulation and analysis framework

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    International audienceThe complexity of modern cosmic ray observatories and therich data sets they capture often require a sophisticated softwareframework to support the simulation of physical processes, detectorresponse, as well as reconstruction and analysis of real andsimulated data. Here we present the EUSO-Offline framework. Thecode base was originally developed by the Pierre AugerCollaboration, and portions of it have been adopted by othercollaborations to suit their needs. We have extended this softwareto fulfill the requirements of Ultra-High Energy Cosmic Raydetectors and very high energy neutrino detectors developed for theJoint Exploratory Missions for an Extreme Universe Observatory(JEM-EUSO). These path-finder instruments constitute a program tochart the path to a future space-based mission like POEMMA. Forcompleteness, we describe the overall structure of the frameworkdeveloped by the Auger collaboration and continue with a descriptionof the JEM-EUSO simulation and reconstruction capabilities. Theframework is written predominantly in modern C++ (compliled againstC++17) and incorporates third-party libraries chosen based onfunctionality and our best judgment regarding support andlongevity. Modularity is a central notion in the framework design, arequirement for large collaborations in which many individualscontribute to a common code base and often want to compare differentapproaches to a given problem. For the same reason, the framework isdesigned to be highly configurable, which allows us to contend witha variety of JEM-EUSO missions and observation scenarios. We alsodiscuss how we incorporate broad, industry-standard testing coveragewhich is necessary to ensure quality and maintainability of arelatively large code base, and the tools we employ to support amultitude of computing platforms and enable fast, reliableinstallation of external packages. Finally, we provide a fewexamples of simulation and reconstruction applications usingEUSO-Offline

    EUSO-Offline: A comprehensive simulation and analysis framework

    No full text
    International audienceThe complexity of modern cosmic ray observatories and therich data sets they capture often require a sophisticated softwareframework to support the simulation of physical processes, detectorresponse, as well as reconstruction and analysis of real andsimulated data. Here we present the EUSO-Offline framework. Thecode base was originally developed by the Pierre AugerCollaboration, and portions of it have been adopted by othercollaborations to suit their needs. We have extended this softwareto fulfill the requirements of Ultra-High Energy Cosmic Raydetectors and very high energy neutrino detectors developed for theJoint Exploratory Missions for an Extreme Universe Observatory(JEM-EUSO). These path-finder instruments constitute a program tochart the path to a future space-based mission like POEMMA. Forcompleteness, we describe the overall structure of the frameworkdeveloped by the Auger collaboration and continue with a descriptionof the JEM-EUSO simulation and reconstruction capabilities. Theframework is written predominantly in modern C++ (compliled againstC++17) and incorporates third-party libraries chosen based onfunctionality and our best judgment regarding support andlongevity. Modularity is a central notion in the framework design, arequirement for large collaborations in which many individualscontribute to a common code base and often want to compare differentapproaches to a given problem. For the same reason, the framework isdesigned to be highly configurable, which allows us to contend witha variety of JEM-EUSO missions and observation scenarios. We alsodiscuss how we incorporate broad, industry-standard testing coveragewhich is necessary to ensure quality and maintainability of arelatively large code base, and the tools we employ to support amultitude of computing platforms and enable fast, reliableinstallation of external packages. Finally, we provide a fewexamples of simulation and reconstruction applications usingEUSO-Offline

    Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device

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    This study aimed to validate a wearable device‚Äôs walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinson‚Äôs Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (n‚ÄČ=‚ÄČ97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and ‚ąí‚ÄČ2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application. Trial registration: ISRCTN ‚Äď 12246987

    Constraining models for the origin of ultra-high-energy cosmic rays with a novel combined analysis of arrival directions, spectrum, and composition data measured at the Pierre Auger Observatory

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    Main outcomes of the Phebus FPT1 uncertainty and sensitivity analysis in the EU-MUSA project

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    The Management and Uncertainties of Severe Accidents (MUSA) project was funded in HORIZON 2020 and is coordinated by CIEMAT (Spain). The project aims at consolidating a harmonized approach for the analysis of uncertainties and sensitivities associated with Severe Accidents (SAs) analysis, focusing on source term figures of merit. The Application of Uncertainty Quantification (UQ) Methods against Integral Experiments (AUQMIE ‚Äď Work Package 4 (WP4)), led by ENEA (Italy), was devoted to apply and test UQ methodologies adopting the internationally recognized PHEBUS FPT1 test. FPT1 was chosen to test UQ methodologies because, even though it is a simplified SA scenario, it was representative of the in-vessel phase of a severe accident initiated by a break in the cold leg of a PWR primary circuit. WP4 served as a platform to identify and discuss the issues encountered in the application of UQ methodol ogies to SA analyses (e.g. discuss the UQ methodology, perform the coupling between the SA codes and the UQ tools, define the results post-processing methods, etc.). The purpose of this paper is to describe the MUSA PHEBUS FPT1 uncertainty application exercise with the related specifications and the methodologies used by the partners to perform the UQ exercise. The main outcomes and lessons learned of the analysis are: scripting was in general needed for the SA code and uncertainty tool coupling and to have more flexibility; particular attention should be devoted to the proper choice of the input uncertain parameters; outlier values of figures of merit should be carefully analyzed; the computational time is a key element to perform UQ in SA; the large number of uncertain input parameters may complicate the interpretation of correlation or sensitivity analysis; there is the need for a statistically solid handling of failed calculations

    Simulation studies for the Mini-EUSO detector

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    Mini-EUSO is a mission of the JEM-EUSO program flying onboard the International Space Station since August 2019. Since the first data acquisition in October 2019, more than 35 sessions have been performed for a total of 52 hours of observations. The detector has been observing Earth at night-time in the UV range and detected a wide variety of transient sources all of which have been modelled through Monte Carlo simulations. Mini-EUSO is also capable of detecting meteors and potentially space debris and we performed simulations for such events to estimate their impact on future missions for cosmic ray science from space. We show here examples of the simulation work done in this framework to analyse the Mini-EUSO data. The expected response of Mini-EUSO with respect to ultra high energy cosmic ray showers has been studied. The efficiency curve of Mini-EUSO as a function of primary energy has been estimated and the energy threshold for Cosmic Rays has been placed to be above 1021^{21} eV. We compared the morphology of several transient events detected during the mission with cosmic ray simulations and excluded that they can be due to cosmic ray showers. To validate the energy threshold of the detector, a system of ground based flashers is being used for end-to-end calibration purposes. We therefore implemented a parameterisation of such flashers into the JEM-EUSO simulation framework and studied the response of the detector with respect to such sources

    Invasion success of a Lessepsian symbiont-bearing foraminifera linked to high dispersal ability, preadaptation and suppression of sexual reproduction

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    Among the most successful Lessepsian invaders is the symbiont-bearing benthic foraminifera Amphistegina lobifera. In its newly conquered habitat, this prolific calcifier and ecosystem engineer is exposed to environmental conditions that exceed the range of its native habitat. To disentangle which processes facilitated the invasion success of A. lobifera into the Mediterranean Sea we analyzed a‚ÄČ~‚ÄČ1400 bp sequence fragment covering the SSU and ITS gene markers to compare the populations from its native regions and along the invasion gradient. The genetic variability was studied at four levels: intra-genomic, population, regional and geographical. We observed that the invasion is not associated with genetic differentiation, but the invasive populations show a distinct suppression of intra-genomic variability among the multiple copies of the rRNA gene. A reduced genetic diversity compared to the Indopacific is observed already in the Red Sea populations and their high dispersal potential into the Mediterranean appears consistent with a bridgehead effect resulting from the postglacial expansion from the Indian Ocean into the Red Sea. We conclude that the genetic structure of the invasive populations reflects two processes: high dispersal ability of the Red Sea source population pre-adapted to Mediterranean conditions and a likely suppression of sexual reproduction in the invader. This discovery provides a new perspective on the cost of invasion in marine protists: The success of the invasive A. lobifera in the Mediterranean Sea comes at the cost of abandonment of sexual reproduction

    Operations of the Pierre Auger Observatory

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    The construction of the first stage of the Pierre Auger Observatory, designed for research of ultra-high energy cosmic rays, began in 2001 with a prototype system. The Observatory has been collecting data since early 2004 and was completed in 2008. The Observatory is situated at 1400 m above sea level near Malarg√ľe, (Mendoza province) in western Argentina, covering a vast plain of 3000 squared km, known as the Pampa Amarillo. The Observatory consists of a hybrid detector, in which there are 1660 water-Cherenkov stations, forming the Surface Detector (SD) and 27 peripheral atmospheric fluorescence telescopes, comprising the Fluorescence Detector (FD). Over time, the Auger Observatory has been enhanced with different R&D prototypes and is recently being to an important upgrade called AugerPrime. In the present contribution, the general operations of the SD and FD will be described. In particular the FD shift procedure - executable locally in Malarg√ľe or remotely by teams in control rooms abroad within the Collaboration - and the newly SD shifts (operating since 2019) will be explained. Additionally, the SD and FD maintenance campaigns, as well as the data taking and data handling at a basic level, will be reporte

    Models of classroom assessment for course-based research experiences

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    Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment‚ÄĒ(1) Assessing Laboratory Work and Scientific Thinking; (2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; (3) Appraising Forms of Scientific Communication; and (4) Metacognition of Learning‚ÄĒalong with a set of practices for each aim. These aims and practices of assessment were then integrated with previously developed models of course-based research instruction to reveal an assessment program in which instructors provide extensive feedback to support productive student engagement in research while grading those aspects of research that are necessary for the student to succeed. Assessment conducted in this way delicately balances the need to facilitate students‚Äô ongoing research with the requirement of a final grade without undercutting the important aims of a CRE education
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