The LHCf experiment: modelling cosmic rays at LHC

The LHCf experiment will be installed in 2007 on the LHC collider in the forward direction at 140 m. from the ATLAS interaction point. The purpose of LHCf is to precisely measure the pion production cross section near zero degrees through the measurement of the photons produced in neutral pion decay. This measurement is crucial for the simulation of the showers induced in the atmosphere by very high energy cosmic rays; the 14 TeV energy available in the center of mass frame corresponds in fact to an equivalent energy of 10(17) eV in the laboratory system. The paper focus on the proposed experiment and on the physics results that we expect from i

El desafiament pel coneixement. És l'LHC segur?

The Quest for Knowledge. Is the LHC safe?Experimental Particle Physics using accelerators has currently reached an exciting moment, with the upcoming launch of the Large Hadron Collider (LHC) at the European Laboratory for Particle Physics (CERN). Nonetheless, public opinion has welcomed the news of this research tool with interest but at the same time with reservations

High-Gradient RF laboratory at IFIC for medical applications

General interest has been shown over the last years for compact and more affordable facilities for hadron-therapy. The High-Gradient (HG) know-how and technology for normal-conducting accelerating RF (Radio-Frequency) electron linac (linear accelerator) structures recently developed for projects such as CLIC (CERN), has raised the achievable accelerating gradient from 20-30 MV/m up to 100-120 MV/m. This gain has come through a better understanding of the high-power RF vacuum arcs or breakdowns (BD) phenomena, the development of quantitative HG RF design methods and refinements in fabrication techniques. This can allow for more compact linacs also for protons, which is potentially important in the new trend in hadron-therapy of using linacs able to provide protons of 70-230 MeV or light ions of 100-400 MeV/u. Linacs are of particular interest for medical applications because they can provide a high degree of flexibility for treatment, such as running at 100-400 Hz pulse rate and pulse-to-pulse beam energy (and intensity) variations. This kind of accelerator is very well suited to treat moving organs with 4D multi-painting spot scanning technique. HG operation is limited by the BD phenomena and is characterized by the BD-Rate. New fresh structures initially operate at a reduced performance and must be conditioned through extended high-power rf operation until the maximum operational gradient is reached. This process is a time consuming, and consequently costly task (> 350 million pulses) which is important to understand and reduce. The IFIC HG-RF laboratory is designed to host a high-power and high-repetition rate facility for testing S-Band (2.9985 GHz) normal-conducting RF structures. This facility will allow the development, RF conditioning and studies of the BD phenomena in HG structures.General interest has been shown over the last years for compact and more affordable facilities for hadron-therapy. The High-Gradient (HG) know-how and technology for normal-conducting accelerating RF (Radio-Frequency) electron linac (linear accelerator) structures recently developed for projects such as CLIC (CERN), has raised the achievable accelerating gradient from 20-30 MV/m up to 100-120 MV/m. This gain has come through a better understanding of the high-power RF vacuum arcs or breakdowns (BD) phenomena, the development of quantitative HG RF design methods and refinements in fabrication techniques. This can allow for more compact linacs also for protons, which is potentially important in the new trend in hadron-therapy of using linacs able to provide protons of 70-230 MeV or light ions of 100-400 MeV/u. Linacs are of particular interest for medical applications because they can provide a high degree of flexibility for treatment, such as running at 100-400 Hz pulse rate and pulse-to-pulse beam energy (and intensity) variations. This kind of accelerator is very well suited to treat moving organs with 4D multi-painting spot scanning technique. HG operation is limited by the BD phenomena and is characterized by the BD-Rate. New fresh structures initially operate at a reduced performance and must be conditioned through extended high-power rf operation until the maximum operational gradient is reached. This process is a time consuming, and consequently costly task (> 350 million pulses) which is important to understand and reduce. The IFIC HG-RF laboratory is designed to host a high-power and high-repetition rate facility for testing S-Band (2.9985 GHz) normal-conducting RF structures. This facility will allow the development, RF conditioning and studies of the BD phenomena in HG structures

Study protocol for a pragmatic randomised controlled trial in general practice investigating the effectiveness of acupuncture against migraine

<p>Abstract</p> <p>Background</p> <p>Migraine is a chronic neurologic disease that can severely affect the patient's quality of life. Although in recent years many randomised studies have been carried out to investigate the effectiveness of acupuncture as a treatment for migraine, it remains a controversial issue. Our aim is to determine whether acupuncture, applied under real conditions of clinical practice in the area of primary healthcare, is more effective than conventional treatment.</p> <p>Methods/Design</p> <p>The design consists of a pragmatic multi-centre, three-armed randomised controlled trial, complemented with an economic evaluation of the results achieved, comparing the effectiveness of verum acupuncture with sham acupuncture, and with a control group receiving normal care only.</p> <p>Patients eligible for inclusion will be those presenting in general practice with migraine and for whom their General Practitioner (GP) is considering referral for acupuncture. Sampling will be by consecutive selection, and by randomised allocation to the three branches of the study, in a centralised way following a 1:1:1 distribution (verum acupuncture; sham acupuncture; conventional treatment). Secondly, one patient in three will be randomly selected from each of the acupuncture (verum or sham) groups for a brain perfusion study (by single photon emission tomography). The treatment with verum acupuncture will consist of 8 treatment sessions, once a week, at points selected individually by the acupuncturist. The sham acupuncture group will receive 8 sessions, one per week, with treatment being applied at non-acupuncture points in the dorsal and lumbar regions, using the minimal puncture technique. The control group will be given conventional treatment, as will the other two groups.</p> <p>Discussion</p> <p>This trial will contribute to available evidence on acupuncture for the treatment of migraine. The primary endpoint is the difference in the number of days with migraine among the three groups, between the baseline period (the 4 weeks prior to the start of treatment) and the period from weeks 9 to 12. As a secondary aspect, we shall record the index of laterality and the percentage of change in the mean count per pixel in each region of interest measured by the brain perfusion tomography, performed on a subsample of the patients within the real and sham acupuncture groups.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN98703707.</p

Integración de herramientas de simulación y modelado energético para determinar las emisiones de gases de efecto invernadero en el sector de la edificación

Consulta en la Biblioteca ETSI Industriales (7546)[ES] Con este proyecto se pretende desarrollar una metodología de cálculo de la eficiencia energética de los edificios basada en los requisitos establecidos por la Directiva 2002/91/CE y adaptada al nuevo marco normativo del sector de la edificación en España, determinando la contribución del sector de la edificación a las emisiones de gas de efecto invernadero y proponiendo soluciones constructivas y de instalaciones para mejorar la eficiencia energética y reducir emisiones cumpliendo con el protocolo de Kioto. El estudio se va a realizar sobre las ocho tipologías de edificios a los que, de acuerdo con el Código Técnico de la Edificación, afecta el Documento Básico DB-HE Ahorro de Energía, variando diferentes parámetros constructivos e instalaciones y calculando el consumo energético y las emisiones asociadas a estas; con el objetivo de determinar cuales son las características de diseño más eficientes energéticamente para cada tipo de edificio situándolo en la zona climática correspondiente a Valencia. En este estudio se distinguen tres partes, la demanda energética generada, el consumo de las instalaciones y las emisiones totales de CO2. En la primera parte se pretende determinar que soluciones constructivas son las que generan menor demanda, y cuales son las que tienen mayor influencia en el cambio de la demanda; para ello se va a realizar un análisis por meses de cada uno de los casos y un análisis de los resultados globales, comparando la demanda de calefacción y la de refrigeración. En el estudio del consumo energético se va a comparar que tipo de instalaciones son las que consumen menor energía y, por último para determinar las emisiones de CO2, utilizamos los resultados que genera el programa CALENER, analizando que tipo de instalación es la que produce menores emisiones.Faus Villalba, MÁ. (2008). Integración de herramientas de simulación y modelado energético para determinar las emisiones de gases de efecto invernadero en el sector de la edificación. http://hdl.handle.net/10251/35511.Archivo delegad

Multipole compensation scheme for LHC low-beta insertions

The LHC dynamic aperture in Physics conditions is determined by the field errors in the low-b quadrupoles and these errors set a lower limit to the value of b*. The associated aberrations have been computed with the transfer matrix method which gives particularly simple and efficient formulae for the case of low-b insertions. These formulae have been applied to the LHC case to design a multipole compensation system. The efficiency of the method has been assessed by trajectory tracking

Driving term experiments at CERN

19 pages, 33 figures.-- PACS nrs.: 41.85.-p, 29.27.-a, 05.45.-a.-- ISI Article Identifier: 000245810500010Driving Term experiments have been performed both at small [PS (Proton Synchrotron) Booster] and large accelerators [SPS (Super Proton Synchrotron)] at CERN. The theory of how to measure driving terms is reviewed. A wealth of SPS experiments is shown together with a successful comparison with model calculations. The PS Booster studies aimed at optimizing the machine performance by measuring and correcting selected driving terms.Peer reviewe

On the Importance of Confident Error Bands for Extrapolations of σ(pp)^tot to High Energies

6 pages, 6 figures.-- Communication presented at the 6th World Multiconference on Systemics, Cybernetics and Informatics and 8th International Conference on Information System Analysis and Synthesis (SCI/ISAS 2002, Orlando, Florida, Jul 14-18, 2002).Elastic proton-proton scattering is the most simple process in high-energy hadronic interactions. One of the main tasks in this field is to detemine the total proton cross section σ(pp)^tot in order to reproduce experimental data. Total cross sections are known long ago from accelerator experiments in the energy range sqrt{s} <= 1:8 TeV and in the range sqrt{s} = 6 - 40 TeV from Extensive Air Shower. In order to know the σ(pp)^tot energy behavior within the accelerator data range and beyond, it is generally proceeded to fit the available set data and also to predict data by extrapolation to high energies. However, if we analize the diverse works existing in the literature about the extrapolation problem, we find in some of them that the uncertainty associated to the σ(pp)^tot prediction points is relatively large or even in other cases the corresponding uncertainties associated to their predictions are not reported. Besides, the disagreement existing between the extrapolated data to high energies from accelerator data and cosmic data, widely discussed in the literature, can be better studied, if prediction methods would offer a confident error interval. The main goal of different methods is to minimize the involved errors to obtain highly precise predictions. In this work we present an alternative prediction method that allows to determine a confident statistical error interval around each of the σ(pp)^tot predicted points. Predictions are developed on the basis of the multiple-diffraction model to estimate σ(pp)^tot in the center of mass range 10 - 40 TeV (10^17 - 10^18 eV in lab) which covers both LHC and the highest cosmic ray energies. We conclude that at least in this case the proposed method is not only more precise that the conventionnal Χ2 technique but also more economic from the point of view of calculation time, because the process is based in a unique calculation instead of multiple iterations.Peer reviewe

Performance of the prototype detector for the LHCf experiment

14 pages, 11 figures.-- PACS nrs.: 13.85.Tp; 95.30.Cq; 95.55.Vj; 95.85.Ry.-- ISI Article Identifier: 000248784500012LHCf is a compact experiment for measuring the energy and transverse momentum spectra of the neutral particles emitted in the high rapidity range at an LHC interaction point. The data obtained by LHCf will set a crucial anchor point for calibration of the interaction models used in studies of high-energy cosmic-rays. In this paper, we report results of a beam test of an LHCf prototype detector that was carried out in July-August 2004 at the CERN SPS H4 beamline. We measured electromagnetic showers generated by 50-200 GeV electron primary beams and obtained 3-5% energy resolution as a function of the primary energy. The measured resolution is in good agreement with Monte Carlo simulations. The position resolution of SciFi hodoscope for measurement of the shower axis, 0.12-0.17 mm, was slightly worse than the MC expectation but adequate for the requirements of LHCf. This study gives a firm foundation for final design and fabrication of the LHCf detectors which will be installed in LHC in 2007 and operational in the early stages of LHC commissioning.This work is partly supported by Grant-in-Aid for Scientific Research (B:16403003), Grant-in-Aid for Scientific Research on Priority Areas (Highest Cosmic Rays: 15077205) and Grant-in-Aid for Young Scientists (B:18740141), by the Ministry of Education, Culture, Sports, and Technology (MEXT) of Japan.Peer reviewe