Measurement of atmospheric production depths of muons with the pierre auger observatory

ISBN: volume 1: 978-2-7598-1025-3; volume 2: 978-2-7598-1026-0International audienceThe time structure of muons at ground retains valuable information about the longitudinal development of the hadronic component in extensive air showers. Using the signals collected by the surface detector array of the Pierre Auger Observatory it is possible to reconstruct the Muon Production Depth (MPD) distribution. In this work we explore the main features of these reconstructions for zenith angles around 60° and different energies of the primary particle. From the MPDs we define a new observable, Xμmax as the depth, along the shower axis, where the maximum number of muons is produced. The potentiality of Xμmax to infer the mass composition of cosmic rays is studied

Uncertainties in Atmospheric Muon-Neutrino Fluxes Arising from Cosmic-Ray Primaries

We present an updated calculation of the uncertainties on the atmospheric muon-neutrino flux arising from cosmic-ray primaries. For the first time, we include recent measurements of the cosmic-ray primaries collected since 2005. We apply a statistical technique that allows the determination of correlations between the parameters of the GSHL primary-flux parametrisation and the incorporation of these correlations into the uncertainty on the muon-neutrino flux. We obtain an uncertainty related to the primary cosmic rays of around $(5\text{--}15)\%$, depending on energy, which is about a factor of two smaller than the previously determined uncertainty. The hadron production uncertainty is added in quadrature to obtain the total uncertainty on the neutrino flux, which is reduced by $\approx 5\%$. To take into account an unexpected hardening of the spectrum of primaries above energies of $100$ $\text{GeV}$ observed in recent measurements, we propose an alternative parametrisation and discuss its impact on the neutrino flux uncertainties

Studying the nuclear mass composition of Ultra-High Energy Cosmic Rays with the Pierre Auger Observatory

The Fluorescence Detector of the Pierre Auger Observatory measures the atmospheric depth, $X_{max}$, where the longitudinal profile of the high energy air showers reaches its maximum. This is sensitive to the nuclear mass composition of the cosmic rays. Due to its hybrid design, the Pierre Auger Observatory also provides independent experimental observables obtained from the Surface Detector for the study of the nuclear mass composition. We present $X_{max}$-distributions and an update of the average and RMS values in different energy bins and compare them to the predictions for different nuclear masses of the primary particles and hadronic interaction models. We also present the results of the composition-sensitive parameters derived from the ground level component.Comment: Proceedings of the 12th International Conference on Topics in Astroparticle and Underground Physics, TAUP 2011, Munich, German

Predicting Transport Effects of Scintillation Light Signals in Large-Scale Liquid Argon Detectors

Liquid argon is being employed as a detector medium in neutrino physics and Dark Matter searches. A recent push to expand the applications of scintillation light in Liquid Argon Time Projection Chamber neutrino detectors has necessitated the development of advanced methods of simulating this light. The presently available methods tend to be prohibitively slow or imprecise due to the combination of detector size and the amount of energy deposited by neutrino beam interactions. In this work we present a semi-analytical model to predict the quantity of argon scintillation light observed by a light detector with a precision better than $10\%$, based only on the relative positions between the scintillation and light detector. We also provide a method to predict the distribution of arrival times of these photons accounting for propagation effects. Additionally, we present an equivalent model to predict the number of photons and their arrival times in the case of a wavelength-shifting, highly-reflective layer being present on the detector cathode. Our proposed method can be used to simulate light propagation in large-scale liquid argon detectors such as DUNE or SBND, and could also be applied to other detector mediums such as liquid xenon or xenon-doped liquid argon.Comment: 23 pages, 27 figures, Accepted by EPJ

Haplotype Analysis of the First A4V-SOD1 Spanish Family: Two Separate Founders or a Single Common Founder?

A4V; SOD1; Esclerosi lateral amiotròficaA4V; SOD1; Esclerosis lateral amiotróficaA4V; SOD1; Amyotrophic lateral sclerosisDespite the genetic heterogeneity reported in familial amyotrophic lateral sclerosis (ALS) (fALS), Cu/Zn superoxide-dismutase (SOD1) gene mutations are the second most common cause of the disease, accounting for around 20% of all families (ALS1) and isolated sporadic cases (sALS). At least 186 different mutations in the SOD1 gene have been reported to date. The possibility of a single founder and separate founders have been investigated for D90A (p.D91A) and A4V (p.A5V), the most common mutations worldwide. High-throughput single nucleotide polymorphism genotyping studies have suggested two founders for A4V (one for the Amerindian population and another for the European population) although the possibility that the two populations are descended from a single ancient founder cannot be ruled out. We used 15 genetic variants spanning the human chromosome 21 from the SOD1 gene to the SCAF4 gene, comparing them with the population reference panels, to demonstrate that the first A4V Spanish pedigree shared the genetic background reported in the European population.This study has been supported by Instituto de Salud Carlos III (grant numbers PIS-FEDER PI16/01673 and PI19/00593). JG and JV-T are the recipients of grant 2017SGR00939 from Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) of the Generalitat de Catalunya

Reflections on the Implementation of Tidal Energy in Ecuador

Renewable energy is a topic frequently discussed due to the need to change the forms of generation, from the centralized to the distributed form and take advantage of the potentials that are scattered in the territory and use local resources and thereby diversify the schemes of distributed generation that allows the man in his daily work to pass from consumption of energy to generator, in this way the environmental impacts are reduced that today accelerate the change of temperature in the planet, noticing in recent years the oil and its derivatives are responsible for this phenomenon. The objective of the research is to reflect on tidal energy, knowing that the province of Manabí, is the one that has the largest coastal area and where there is a potential that can be studied for future use