Trigger and Aperture of the Surface Detector Array of the Pierre Auger Observatory

The surface detector array of the Pierre Auger Observatory consists of 1600 water-Cherenkov detectors, for the study of extensive air showers (EAS) generated by ultra-high-energy cosmic rays. We describe the trigger hierarchy, from the identification of candidate showers at the level of a single detector, amongst a large background (mainly random single cosmic ray muons), up to the selection of real events and the rejection of random coincidences. Such trigger makes the surface detector array fully efficient for the detection of EAS with energy above $3\times 10^{18}$ eV, for all zenith angles between 0$^\circ$ and 60$^\circ$, independently of the position of the impact point and of the mass of the primary particle. In these range of energies and angles, the exposure of the surface array can be determined purely on the basis of the geometrical acceptance.Comment: 29 pages, 12 figure

Ultrahigh energy neutrinos at the Pierre Auger observatory

The observation of ultrahigh energy neutrinos (UHEνs) has become a priority in experimental astroparticle physics. UHEνs can be detected with a variety of techniques. In particular, neutrinos can interact in the atmosphere (downward-going ν) or in the Earth crust (Earth-skimming ν), producing air showers that can be observed with arrays of detectors at the ground. With the surface detector array of the Pierre Auger Observatory we can detect these types of cascades. The distinguishing signature for neutrino events is the presence of very inclined showers produced close to the ground (i.e., after having traversed a large amount of atmosphere). In this work we review the procedure and criteria established to search for UHEνs in the data collected with the ground array of the Pierre Auger Observatory. This includes Earth-skimming as well as downward-going neutrinos. No neutrino candidates have been found, which allows us to place competitive limits to the diffuse flux of UHEνs in the EeV range and above.P. Abreu ... K. B. Barber ... J. A. Bellido ... R. W. Clay ... M. J. Cooper ... B. R. Dawson ... T. A. Harrison ... A. E. Herve ... V. C. Holmes ... J. Sorokin ... P. Wahrlich ... B. J. Whelan ... et al

Electron Injection to Unoccupied Electronic States in Organic Semiconductor Thin Films Studied by Inverse Photoemission Spectroscopy (INTERFACE SCIENCE-Molecular Aggregates)

Inverse photoemission spectroscopy (IPES) in the vacuum ultraviolet region was applied to directly observe behaviors of electron injection into unoccupied electronic states in perylene-3,4,9,10- tetracarboxylic dianhydride (PTCDA) thin films due to alkali metal. By the analysis of the observed results the amount of injected electrons per PTCDA molecule was evaluated with relation to the dopant concentration. The derived relationship has been explained with the aid of DV-X calculations of energy levels concerned

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8\ub10.7(stat)\ub16.7(syst)\u2009\u2009MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory

Radiopure ZnMoO4 scintillating bolometers for the LUMINEU double-beta experiment

The results of R&D of radiopure zinc molybdate (ZnMoO4) based scintillating bolometers for the LUMINEU (Luminescent Underground Molybdenum Investigation for NEUtrino mass and nature) double-beta decay experiment are presented. A dedicated two-stage molybdenum purification technique (sublimation in vacuum and recrystallization from aqueous solutions) and an advanced directional solidification method (the low-thermal-gradient Czochralski technique) were utilized to produce high optical quality large mass (∼1 kg) ZnMoO4 crystal boules and first 100Mo (99.5%) enriched Zn100MoO4 crystal scintillator (mass of ∼0.2 kg). Scintillating bolometers based on ZnMoO4 (≈ 0.33 kg) and Zn100MoO4 (≈ 0.06 kg) scintillation elements and high purity Ge wafers were tested in the EDELWEISS set-up at the Modane Underground Laboratory (France). Long term low temperature tests demonstrate excellent detectors’ performance and effectiveness of the purification and solidification procedures for the achievement of high radiopurity of the material, in particular with a bulk activity of 228Th and 226Ra below 4 µBq/kg. The adopted protocol was used to produce for the first time a large volume Zn100MoO4 crystal scintillator (mass of ∼1.4 kg, 100Mo enrichment is 99.5%) to search for neutrinoless double-beta decay of 100Mo in the framework of the LUMINEU project.Expérience souterraine avec détecteurs luminescents de molybdate de zinc pour l'étude de la masse et la nature des neutrino

Development and underground test of radiopure ZnMoO4 scintillating bolometers for the LUMINEU 0 nu 2 beta project

The LUMINEU (Luminescent Underground Molybdenum Investigation for NEUtrino mass and nature) project envisages a high-sensitivity search for neutrinoless double beta (0 nu 2 beta) decay of Mo-100 with the help of scintillating bolometers based on zinc molybdate (ZnMoO4) crystals. One of the crucial points for the successful performance of this experiment is the development of a protocol for producing high quality large mass ZnMoO4 crystal scintillators with extremely high internal radiopurity. Here we report a significant progress in the development of large volume ZnMoO4 crystalline boules (with mass up to 1 kg) from deeply purified materials. We present and discuss the results achieved with two ZnMoO4 samples (with mass of about 0.3 kg each): one is a precursor of the LUMINEU project, while the other one was produced in the framework of LUMINEU with an improved purification / crystallization procedure. The two crystals were measured deep underground as scintillating bolometers in the EDELWEISS dilution refrigerator at the Laboratoire Souterrain de Modane (France) protected by a rock overburden corresponding to 4800 m w.e. The results indicate that both tested crystals are highly radiopure. However, the advanced LUMINEU sample shows a clear improvement with respect to the precursor, exhibiting only a trace internal contamination related with Po-210 at the level of 1 mBq/kg, while the activity of Ra-226 and Th-228 is below 0.005 mBq/kg. This demonstrates that the LUMINEU purification and crystal-growth procedures are very efficient and leads to radiopurity levels which exceedingly satisfy not only the LUMINEU goals but also the requirements of a next-generation 0 nu 2 beta experiment.Expérience souterraine avec détecteurs luminescents de molybdate de zinc pour l'étude de la masse et la nature des neutrino

The beam and detector for the NA48 neutral kaon CP violation experiment at CERN

The beam and detector, used for the NA48 experiment, devoted to the measurement of Re(epsilon'/epsilon) and for the NA48/1 experiment onrare K S and neutral hyperon decays, are described

Impacto del proyecto PERSECC en la productividad de las MYPES de calzado de la ciudad de Trujillo, 2017

RESUMEN La presente investigación tiene como propósito determinar el impacto del proyecto creado por la Oficina de Proyectos de Investigación, Desarrollo e Innovación de CITEccal Trujillo, el “Proyecto de Reactivación del Sector Cuero y Calzado” en la productividad de las MYPES del sector calzado en relación con la incidencia que tenga este con el comportamiento de las ventas, producción y demás indicadores de las empresas que aplicaron a PERSECC durante el año 2017, con la finalidad de demostrar la labor del Estado al tomar medidas orientadas a elevar los niveles de competitividad de las empresas en estudio en relación a la reactivación de dicho sector. Para el desarrollo del presente trabajo de investigación, se utilizaron fuentes de información primaria debido a que serán documentos directos que se obtendrán de la oficina de Investigación, Desarrollo e Innovación de CITEccal Trujillo. Para esto, se tuvo en cuenta el análisis de la documentación de los datos recopilados del registro anual y evolución trimestral de ventas, producción, capacidad instalada, capacidad productiva, inversión en I+D+i, recurso humano, plan de acción del programa PERSECC, los cuales fueron facilitados directamente del área de la oficina de proyectos I+D+i para la realización del proyecto. Luego, se recopilaron los datos a través del análisis documental para ser procesados en tablas y gráficos, en seguida se determinaron las medias usando la Prueba T - Student para datos relacionados (muestras dependientes). Finalmente para medir la relación entre las variables en estudio se calculó el valor de probabilidad estadístico por el cual se rechaza la hipótesis nula y se acepta la hipótesis alternativa. De esta manera, la investigación llega a la conclusión que existen diferencias estadísticamente significativas entre los valores trimestrales de todos los indicadores analizados de las MYPES de calzado de la ciudad de Trujillo anteriores y posteriores de la aplicación del proyecto PERSECC, lo que significa que el proyecto PERSECC incide de manera significativa en la evolución de los indicadores de la productividad de cada una de las empresas del sector Calzado que aplicaron al proyecto. La principal recomendación que se hace al área de Proyectos I+D+i, es que el jefe de Proyectos autorice la continuación de la aplicación anual del Proyecto PERSECC con la finalidad de ampliar la participación de más MYPES, manteniendo un continuo control del registro de la data con respecto a la evaluación y seguimiento de indicadores en la mejora de su productividad y de esta manera, definir mejor el apoyo de la labor que viene realizando el CITEccal Trujillo para el aumento de la competitividad de las empresas del sector calzado. Palabras clave: Proyecto, Soporte Productivo, I+D, Productividad, Mypes (Micro y Pequeñas Empresas), Sector Calzado, Producción Calzado, Comercio Calzado.ABSTRACT The purpose of this research is to determine the impact of the project created by the Research, Development and Innovation Projects Office of CITEccal Trujillo, the "PERSECC" project in the productivity of the MSEs of the footwear sector in relation to the impact that this has with the behavior of sales, production and other indicators of the companies that applied to PERSECC during the year 2017, in order to demonstrate the work of the State to take measures aimed at raising the levels of competitiveness of companies under study in relation to the reactivation of this sector. For the development of this research work, primary information sources were used because they will be direct documents that will be obtained from the Research, Development and Innovation office of CITEccal Trujillo. For this, the analysis of the documentation of the annual record and quarterly evolution of sales, production, installed capacity, productive capacity, investment in R & D & I, human resources, action plan of the PERSECC program was taken account, which were provided directly from the area of the R + D + i project office for the realization of the project. Then, the data was collected through the documentary analysis to be processed in tables and graphs, consequently sample means were determined using the T - Student test for related data (dependent samples). Finally, to measure the relationship between the variables under study, it has been estimated the statistical probability value by which the null hypothesis is rejected and the alternative hypothesis is accepted. The main recommendation made to the area of R + D + i Projects, is that the Project Manager continues to authorize the application of the PERSECC Project in the coming years in order to expand the participation of more MYPES, maintaining a continuous control of the registry of the data with respect to the evaluation and monitoring of indicators to improve their productivity and, in this way, better define the support of the work that CITEccal Trujillo has been doing to increase the competitiveness of companies in the footwear sector