In the context of formal modeling and verification of complex systems composed of cycling entities, we propose a method allowing to speed up the construction of state spaces exploiting symmetries. The method is suitable for systems continuously updating large data but whose transitions do not depend on the particular data values. Using a judicious ordering of operations, the method avoids non-necessary multiple treatments thus allowing to factorize a part of the computations. We prove that the method is correct and complete, and illustrate its application on a case study composed of a network of cycling timed automata extended with data.
We present measurements of the atmospheric depth of the shower maximum X-max, inferred for the first time on an event-by-event level using the surface detector of the Pierre Auger Observatory. Using deep learning, we were able to extend measurements of the X-max distributions up to energies of 100 EeV (10(20) eV), not yet revealed by current measurements, providing new insights into the mass composition of cosmic rays at extreme energies. Gaining a 10-fold increase in statistics compared to the fluorescence detector data, we find evidence that the rate of change of the average X-max with the logarithm of energy features three breaks at 6.5 +/- 0.6(stat) +/- 1(syst) EeV, 11 +/- 2(stat)+/- 1(syst)EeV, and 31 +/- 5(stat)+/- 3(syst)EeV, in the vicinity to the three prominent features (ankle, instep, suppression) of the cosmic-ray flux. The energy evolution of the mean and standard deviation of the measured X-max distributions indicates that the mass composition becomes increasingly heavier and purer, thus being incompatible with a large fraction of light nuclei between 50 and 100 EeV.
Radiative capture cross section strongly depends on the electromagnetic de-excitation probability, hence on the so-called photon strength function (PSF) and nuclear level density (NLD). Microscopic models for both PSF and NLD have been developed for the past decades but remain affected by fundamental assumptions, like the independent particle approximation for NLD and the assumption that the de-excitation PSF is equal to the photoabsorption PSF. The present study goes beyond the existing models by providing a common framework based on QRPA estimates of nuclear excitations that are used to derive NLD by coupling QRPA bosons as well as the de-excitation PSF by calculating all possible transition probabilities between QRPA states. The present framework is found to reproduce experimental data related to both NLD and PSF accurately, provided QRPA excitation energies are globally reduced by an energy-dependent shift. More specifically, the resulting NLDs, also extended to odd-A and odd-odd nuclei, are shown to be in good agreement with experimental s-wave resonance spacings and the photoabsorption PSF with photodata. Interestingly, the estimated E1 de-excitation PSF is found to be close to the photoabsorption PSF for excitation energies below typically 10-12 MeV, validating the Brink hypothesis in this energy region, but to significantly differ above, especially for spherical nuclei. In contrast, the M1 de-excitation PSF deviates strongly from the photoabsorption one both at low photon energies where an enhancement, the so-called "upbend", is clearly predicted and at higher photon energies where it lies far below the spin-flip component. For spherical nuclei, the de-excitation PSF increases the radiative neutron capture cross section appreciably, while a modest impact is obtained for deformed nuclei.
The Pierre Auger Collaboration has embraced the concept of open access to their research data since its foundation, with the aim of giving access to the widest possible community. A gradual process of release began as early as 2007 when 1% of the cosmic-ray data was made public, along with 100% of the space-weather information. In February 2021, a portal was released containing 10% of cosmic-ray data collected by the Pierre Auger Observatory from 2004 to 2018, during the first phase of operation of the Observatory. The Open Data Portal includes detailed documentation about the detection and reconstruction procedures, analysis codes that can be easily used and modified and, additionally, visualization tools. Since then, the Portal has been updated and extended. In 2023, a catalog of the highest-energy cosmic-ray events examined in depth has been included. A specific section dedicated to educational use has been developed with the expectation that these data will be explored by a wide and diverse community, including professional and citizen scientists, and used for educational and outreach initiatives. This paper describes the context, the spirit, and the technical implementation of the release of data by the largest cosmic-ray detector ever built and anticipates its future developments.
Numerous grading scales were proposed for subarachnoid hemorrhage (SAH) to assess the likelihood of unfavorable neurological outcomes (UO) and the risk of delayed cerebral ischemia (DCI). We aimed to validate the Hemorrhage, Age, Treatment, Clinical Status, and Hydrocephalus (HATCH) score and the VASOGRADE, a simple grading scale for prediction of DCI after aneurysmal SAH. This was a retrospective single-center study of patients with nontraumatic SAH (January 2016 to December 2021) admitted to the intensive care unit. We performed a receiver operating characteristic (ROC) curve analysis to assess the discriminative ability of the HATCH and the VASOGRADE to identify patients who had UO at 3 months (defined as Glasgow Outcome Scale score of 1–3), hospital mortality, and DCI and compared their performance with the World Federation of Neurosurgical Surgeons, the modified Fisher, the Sequential Organ Failure Assessment, and the Acute Physiology and Chronic Health Evaluation II scales. We performed a multivariate logistic regression analysis to assess the association between HATCH and UO at 3 months and between VASOGRADE and DCI. We included 262 consecutive patients with nontraumatic SAH. DCI was observed in 82 patients (31.3
