Measurement of the neutron capture cross section of the ²³⁵U at the n_TOF facility

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Física Teórica II, leída el 08-11-2017Las actuales y futuras demandas de energía requieren el desarrollo de nuevas fuentes de producción así como la mejora de las ya existentes. El primer y crucial ingrediente para el diseño de los reactores nucleares y el ciclo de combustible son los datos nucleares. A la hora de diseñar y evaluar la seguridad de los reactores nucleares es necesario una gran cantidad de datos nucleares para distintos materiales. Los ingenieros y físicos deben afrontar diferentes variantes de los reactores nucleares y realizar grandes cálculos para estimar el rendimiento de los sistemas nucleares críticos. Para tener estimaciones fiables, estos estudios deben incoporar las secciones eficaces más precisas que se conocen, habitualmente incluidas en las librerias evualadas tales como ENDF/B-VII.1, JENDL-4.0a o JEFF-3.2. Estas librer¿¿as evaluadas son probadas con experimentos integrales y de esta manera se valida los actuales datos y secciones eficaces nucleares. Estas librer¿¿as predicen de manera muy precisa para la mayoria de sistemas nucleares cr¿¿ticos su comportamiento. Sin embargo, la buena estimación en estos experimentos integrales crea la falsa sensación de optimismo debido a la compensación de errores, calibraciones de los datos y discrepancias entre librer¿¿as. El objetivo de este manuscrito es presentar el análisis y resultados de la medida de la sección eficaz de captura del 235 U llevado a cabo en la instalación n TOF del CERN en el rango de energ¿¿as del neutrón desde 0.2 a 200 eV. Estos datos han sido utilizados para el desarrollo de una nueva libreria evaluada de secciones eficaces de neutrones que será usada en el diseño y desarrollo de nuevos reactores nucleares.Depto. de Física TeóricaFac. de Ciencias FísicasTRUEunpu

Identificación de perfiles de viento en banco de ensayos y monitorización de aerogeneradores para aplicaciones en minieólica

El objeto fundamental del proyecto es el estudio del comportamiento del aerogenerador comercial DS – 300. Se trata de un proyecto enmarcado en el sector de energías renovables, concretamente dentro de la rama de energía eólica. Esta energía es asociada normalmente a los aerogeneradores de alta potencia, que se agrupan formando parques eólicos, los cuales son propiedad de las grandes empresas generadoras de electricidad (En España, principalmente Iberdrola y Endesa), y que se emplean para inyectar energía a la red eléctrica.Escuela Técnica Superior de Ingeniería IndustrialUniversidad Politécnica de Cartagen

First measurement of the 94Nb(n,γ) cross section at the CERN n_TOF facility

One of the crucial ingredients for the improvement of stellar models is the accurate knowledge of neutron capture cross-sections for the different isotopes involved in the s-,r- and i- processes. These measurements can shed light on existing discrepancies between observed and predicted isotopic abundances and help to constrain the physical conditions where these reactions take place along different stages of stellar evolution. In the particular case of the radioactive 94Nb, the 94Nb(n,γ) cross-section could play a role in the determination of the s-process production of 94Mo in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous 94Nb(n,γ) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing highquality samples and also due to limitations in conventional detection systems commonly used in time-of-flight experiments. Motivated by this situation, a first measurement of the 94Nb(n,γ) reaction was carried out at CERN n_TOF, thereby exploiting the high luminosity of the EAR2 area in combination with a new detection system of small-volume C6D6-detectors and a high quality 94Nb-sample. The latter was based on hyper-pure 93Nb material activated at the high-flux reactor of ILL-Grenoble. An innovative ring-configuration detection system in close geometry around the capture sample allowed us to significantly enhance the signal-to-background ratio. This set-up was supplemented with two conventional C6D6-detectors and a highresolution LaCl3(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties. At the current status of the data analysis, 18 resonance in 94Nb+n have been observed for the first time in the neutron energy range from thermal up to 10 keV.European Research Council (ERC)European Union’s Horizon 2020 research and innovation programme (ERC Consolidator Grant project HYMNS, with grant agreement No. 681740)ICJ220-045122-IMCIN/AEI/ 10.13039/501100011033European Union NextGenerationEU/PRTRSpanish Ministerio de Ciencia e Innovación under grants PID2019-104714GB-C21, FPA2017-83946-C2-1-P, FIS2015-71688-ERCCSICPIE-201750I2

Session A3: LIFE+ Segura Riverlink, Implementing a Green Infrastructure Approach

Abstract: The Segura River, located in southeastern Spain, is one of the most regulated rivers in Europe, creating severe environmental problems and breaking connectivity. The LIFE + SEGURA RIVERLINK project, cofinanced by the LIFE Program, aims to promote and support the environmental recovery of the Segura River Basin by improving and strengthening the connectivity between natural ecosystems, promoting the conservation of an area with an exceptional environmental value and improving its public use. The main actions include the removal of an unused weir and the construction of eight fish passages, being this a pilot experience in the Segura River Basin and a still uncommon practice in Mediterranean areas. To support these actions, ecological restorations will be implemented in each demonstration site. The target specie of the project is the Luciobarbus sclateri (Southern Iberian barbel), Iberian endemism and the only autochthonous specie in the project. The rest of sentinel species are Pseudochondrostoma polylepis (Iberian nase), Gobio lozanoi (Pyrenean gudgeon) and Alburnus alburnus (Bleak). Monitoring activities will assess the performance of these actions with the hope of validating the Green Infrastructure approach in river basin management and its possible extension to the official River Basin Management Plan of the Segura River Basin. The project also includes the creation of a Land Stewardship Network that seeks to involve different stakeholders in the river management as well as an Environmental Educational Program and a Volunteering Program to promote environmental awareness in society. This project will protect local aquatic and riverine habitats, allow fish migration along an important sector of the Segura River, improve ecosystem services, build a cadre of scientific and social knowledge to improve river management quality and help local and regional governments to comply with EU Water Framework Directive and facilitate the implementation and enforcement of EU policy and legislation on biodiversity conservation

Thermal neutron background at Laboratorio Subterráneo de Canfranc (LSC)

The thermal neutron background at Laboratorio Subterráneo de Canfranc (LSC) has been determined using several He proportional counter detectors. Bare and Cd shielded counters were used in a series of long measurements. Pulse shape discrimination techniques were applied to discriminate between neutron and gamma signals as well as other intrinsic contributions. Montecarlo simulations allowed us to estimate the sensitivity of the detectors and calculate values for the background flux of thermal neutrons inside Hall-A of LSC. The obtained value is (3.5±0.8)×10 n/cms, and is within an order of magnitude compared to similar facilities.This work was supported partially by the Spanish Ministerio de Ciencia e Innovación and its Plan Nacional de I+D+i de Física de Partículas projects: FPA2016-76765-P and FPA2018-096717-B-C21. The authors want to acknowledge the help provided by the staff at LSC in the preparation and support for this work

Measurement of the neutron capture cross section of the fissile isotope 235U with the CERN n-TOF total absorption calorimeter and a fission tagging based on micromegas detectors

The accuracy on neutron capture cross section of fissile isotopes must be improved for the design of future nuclear systems such as Gen-IV reactors and Accelerator Driven Systems. The High Priority Request List of the Nuclear Energy Agency, which lists the most important nuclear data requirements, includes also the neutron capture cross sections of fissile isotopes such as 233,235U and 239,241Pu. A specific experimental setup has been used at the CERN n TOF facility for the measurement of the neutron capture cross section of 235U by a set of micromegas fission detectors placed inside a segmented BaF2 Total Absorption Calorimeter.Plan Nacional de I+D+I Física de particulas FPA2014-53290-C2-

Neutron capture measurements with high efficiency detectors and the Pulse Height Weighting Technique

Neutron capture cross section measurements in time-of-flight facilities are usually performed by detecting the prompt γ-rays emitted in the capture reactions. One of the difficulties to be addressed in these measurements is that the emitted γ-rays may change with the neutron energy, and therefore also the detection efficiency. To deal with this situation, many measurements use the so called Total Energy Detection (TED) technique, usually in combination with the Pulse Height Weighting Technique (PHWT). With it, it is sought that the detection efficiency depends only on the total energy of the γ-ray cascade, which does not vary much with the neutron energy. This technique was developed in the 1960s and has been used in many neutron capture experiments to date. One of the requirements of the technique is that γ-ray detectors have a low efficiency. This has meant that the PHWT has been used with experimental setups with low detection efficiencies. However, this condition does not have to be fulfilled by the experimental system as a whole. The main goal of this work is to show that it is possible to measure with a high efficiency detection system that uses the PHWT, and how to analyze the measured data.This work was supported in part by the I+D+i grant PGC2018- 096717-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by the European Commission H2020 Framework Programme project SANDA (Grant agreement ID: 847552)

Measurement of the α ratio and (n, γ) cross section of 235U from 0.2 to 200 eV at n_TOF

We measured the neutron capture-to-fission cross-section ratio (α ratio) and the capture cross section of 235U between 0.2 and 200 eV at the n_TOF facility at CERN. The simultaneous measurement of neutron-induced capture and fission rates was performed by means of the n_TOF BaF2 Total Absorption Calorimeter (TAC), used for detection of γ rays, in combination with a set of micromegas detectors used as fission tagging detectors. The energy dependence of the capture cross section was obtained with help of the 6 Li(n,t) standard reaction determining the n_TOF neutron fluence; the well-known integral of the 235U(n, f ) cross section between 7.8 and 11 eV was then used for its absolute normalization. The α ratio, obtained with slightly higher statistical fluctuations, was determined directly, without need for any reference cross section. To perform the analysis of this measurement we developed a new methodology to correct the experimentally observed effect that the probabilities of detecting a fission reaction in the TAC and the micromegas detectors are not independent. The results of this work have been used in a new evaluation of 235U performed within the scope of the Collaborative International Evaluated Library Organisation (CIELO) Project, and are consistent with the ENDF/B-VIII.0 and JEFF-3.3 capture cross sections below 4 eV and above 100 eV. However, the measured capture cross section is on average 10% larger between 4 and 100 eV.Ministerio de Economía, Industria y Competitividad de España. FPA2014-53290-C2-1, FPA2016-76765- P y FPA2017-82647-P7º Programa Marco CHANDA de la Comisión Europea. FP7-60520

Surgical Infection Reduction Program of the Observatory of Surgical Infection (PRIQ-O): Delphi prioritization and consensus document on recommendations for the prevention of surgical site infection

La infección de localización quirúrgica es la complicación más frecuente y más evitable de la cirugía, pero las guías clínicas para su prevención tienen un seguimiento insuficiente. Presentamos los resultados de un consenso Delphi realizado por un panel de expertos de 17 sociedades científicas con revisión crítica de la evidencia científica y guías internacionales, para seleccionar las medidas con mayor grado de evidencia y facilitar su implementación. Se revisaron 40 medidas y se emitieron 53 recomendaciones. Se priorizan 10 medidas principales para su inclusión en bundles de prevención: ducha preoperatoria; correcta higiene quirúrgica de manos; no eliminación del vello del campo quirúrgico o eliminación con maquinilla eléctrica; profilaxis antibiótica sistémica adecuada; uso de abordajes mínimamente invasivos; descontaminación de la piel con soluciones alcohólicas; mantenimiento de la normotermia; protectores-retractores plásticos de herida; cambio de guantes intraoperatorio, y cambio de material quirúrgico y auxiliar antes del cierre de las heridasSurgical site infection is the most frequent and avoidable complication of surgery, but clinical guidelines for its prevention are insufficiently followed. We present the results of a Delphi consensus carried out by a panel of experts from 17 Scientific Societies with a critical review of the scientific evidence and international guidelines, to select the measures with the highest degree of evidence and facilitate their implementation. Forty measures were reviewed and 53 recommendations were issued. Ten main measures were prioritized for inclusion in prevention bundles: preoperative shower; correct surgical hand hygiene; no hair removal from the surgical field or removal with electric razors; adequate systemic antibiotic prophylaxis; use of minimally invasive approaches; skin decontamination with alcoholic solutions; maintenance of normothermia; plastic wound protectors-retractors; intraoperative glove change; and change of surgical and auxiliary material before wound closur