Cosmic Ray Physics with ACORDE at LHC

The use of large underground high-energy physics experiments, for comic ray studies, have been used, in the past, at CERN, in order to measure, precisely, the inclusive cosmic ray flux in the energy range from 2x10^10 - 2x10^12 eV. ACORDE, ALICE Cosmic Rays DEtector, will act as Level 0 cosmic ray trigger and, together with other ALICE apparatus, will provide precise information on cosmic rays with primary energies around 10^15 - 10^17 eV. This paper reviews the main detector features, the present status, commissioning and integration with other apparatus. Finally, we discuss the ACORDE-ALICE cosmic ray physics program.Comment: Contribution to the 2007 Europhysics Conference on High Energy Physics - Manchester, England 19-25 July 2007; 3 pages, 3 figure

Assessment of the worthwhileness of efficient driving in railway systems with high-receptivity power supplies

Eco-driving is one of the most important strategies for significantly reducing the energy consumption of railways with low investments. It consists of designing a way of driving a train to fulfil a target running time, consuming the minimum amount of energy. Most eco-driving energy savings come from the substitution of some braking periods with coasting periods. Nowadays, modern trains can use regenerative braking to recover the kinetic energy during deceleration phases. Therefore, if the receptivity of the railway system to regenerate energy is high, a question arises: is it worth designing eco-driving speed profiles? This paper assesses the energy benefits that eco-driving can provide in different scenarios to answer this question. Eco-driving is obtained by means of a multi-objective particle swarm optimization algorithm, combined with a detailed train simulator, to obtain realistic results. Eco-driving speed profiles are compared with a standard driving that performs the same running time. Real data from Spanish high-speed lines have been used to analyze the results in two case studies. Stretches fed by 1 × 25 kV and 2 × 25 kV AC power supply systems have been considered, as they present high receptivity to regenerate energy. Furthermore, the variations of the two most important factors that affect the regenerative energy usage have been studied: train motors efficiency ratio and catenary resistance. Results indicate that the greater the catenary resistance, the more advantageous eco-driving is. Similarly, the lower the motor efficiency, the greater the energy savings provided by efficient driving. Despite the differences observed in energy savings, the main conclusion is that eco-driving always provides significant energy savings, even in the case of the most receptive power supply network. Therefore, this paper has demonstrated that efforts in improving regenerated energy usage must not neglect the role of eco-driving in railway efficiency

Precision Determination of the Top Quark Mass

The CDF and D0 collaborations have updated their measurements of the mass of the top quark using proton-antiproton collisions at sqrt{s}=1.96TeV produced at the Tevatron. The uncertainties in each of the of top-antitop decay channels have been reduced. The new Tevatron average for the mass of the top quark based on about 1/fb of data per experiment is 170.9+-1.8GeV/c^2.Comment: 14 pages, 4 figures; LaTeX2e, 8 .eps files, uses LaThuileFPSpro.sty (included). To appear in the proceedings of the 21st Rencontres des Physique de la Vallee d'Aoste, La Thuile, March 4-10, 200

Implementation of environmental recovery training response to biological incidents in a human health degree

Agents involved in biological incidents and outbreaks of infection can spread easily, so response teams are required to quickly implement a recovery plan to decontaminate and restore the environment impacted by these incidents to minimise public risks. A group of academics at De Montfort University (DMU, UK), with support from first responders during the 2014-16 Ebola outbreak, are developing appropriate training to provide basic skills so human health science students can respond to biological incidents. Following the competences identified by the European Commission, we have created key competences for these students based on the core skills that any medical first responder to biological emergencies should have. To provide students with the key competences related to environmental planning, we have created specific training that consisted of a 2 hours practical plus theory related to emerging diseases and the international response provided to tackle the Ebola pandemic. The practical component was a research-led workshop to develop a complete protection and recovery plan to respond to an outbreak of infection by Cyclospora cayetanensis in an urban area. Students used the novel methodology developed by Public Health England [“UK Recovery Handbook for Biological Incidents” (Pottage et al., 2015)] [1] to select appropriate options or techniques to protect and recover the affected environment, according to the physiological characteristics of the biological agent/microorganism involved and the environment impacted. Critical thinking and discussion is also needed to select recovery options (R.O.), e.g. use of chlorine-based decontamination liquids as part of the R.O. “reactive liquids” will have limited efficacy as oocysts of Cyclospora are resistant to these. After successful testing of the training with postgraduate students, we introduced it in a level 6 module in the DMU degree programme BMedSci in Medical Science in 2016/17 (n=24). A small proportion of these BMedSci students reported that they did not enjoy (13.4%) or were not satisfied (20%) with the training provided, which could be attributed to the fact that the topic of the training (environmental sciences) was not of direct interest for these students who are studying a degree more related to medicine. However, despite the short duration of the training, students were able to tailor an appropriate response with the resources and information provided (physiological characteristics and a literature review on decontamination/inactivation techniques for Cyclospora was provided to overcome time constraints). Specifically, 73.3% indicated that they gained some public health prevention/preparedness knowledge against a biological incident; 80% highlighted that they learnt how to establish some public health interventions; and 60% learnt how to tailor a recovery plan. A few students (20%) had difficulties with the recovery concepts and the interpretation of the physiological characteristics, which may be attributed to limited background knowledge of microbiology and parasitology (as the BMedSci programme does not have a complete module dedicated to the study of these topics). In conclusion, the increased prevalence of biological contamination incidents necessitates development of appropriate training to include environmental decontamination strategies to protect human health. The short teaching intervention described in this paper could be used to easily address this necessity

Ensemble equivalence for distinguishable particles

Statistics of distinguishable particles has become relevant in systems of colloidal particles and in the context of applications of statistical mechanics to complex networks. When studying these type of systems with the standard textbook formalism, non-physical results such as non-extensive entropies are obtained. In this paper, we will show that the commonly used expression for the partition function of a system of distinguishable particles leads to huge fluctuations of the number of particles in the grand canonical ensemble and, consequently, to non-equivalence of statistical ensembles. We will see how a new proposed definition for the entropy of distinguishable particles by Swendsen [J. Stat. Phys. 107, 1143 (2002)] solves the problem and restores ensemble equivalence. We also show that the new proposal for the partition function does not produce any inconsistency for a system of distinguishable localized particles, where the monoparticular partition function is not extensive

The concentration-compactness principle for variable exponent spaces and applications

In this paper we extend the well-known concentration -- compactness principle of P.L. Lions to the variable exponent case. We also give some applications to the existence problem for the $p(x)-$Laplacian with critical growth