Statistical and systematical errors in analyses of separate experimental data sets in high energy physics

Different ways of extracting parameters of interest from combined data sets of separate experiments are investigated accounting for the systematic errors. It is shown, that the frequentist approach may yield larger $\chi^2$ values when compared to the Bayesian approach, where the systematic errors have a Gaussian distributed prior calculated in quadrature. The former leads to a better estimation of the parameters. A maximum-likelihood method, applied to different "gedanken" and real LHC data, is presented. The results allow to choose an optimal approach for obtaining the fit based model parameters.Comment: 24 pages, 1 figur

Low missing mass, single- and double diffraction dissociation at the LHC

Low missing mass, single- and double diffraction dissociation is calculated for the LHC energies from a dual-Regge model, dominated by a Pomeron Regge pole exchange. The model reproduces the rich resonance structure in the low missing mass Mx region. The diffractionly excited states lie on the nucleon trajectory, appended by the isolated Roper resonance. Detailed predictions for the squared momentum transfer and missing mass dependence of the differential and integrated single- and double diffraction dissociation in the kinematical range of present and future LHC measurements are given. The model predicts a possible turn-down of the cross section towards, t -> 0 in a region probably accessible in future experiments in the nearly forward direction. The present work is a continuation and extension (e.g. with double diffraction) of a previous work using the dual Regge approach

Mechanisms of the plastic deformation of molybdenum

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Google Maps -selainsovelluksen toteutus Bing Mapsilla

Opinnäytetyön aiheena oli kehitystyö Google Mapsin APIa käyttävään selainsovellukseen. Kehitystyön tarkoituksena oli lisätä sovellukseen tuki Bing Mapsille. Tuki Bing Mapsille haluttiin, koska osa Bing Mapsin satelliittikuvista on Google Mapsin satelliittikuvia parempia. Tavoitteena oli toteuttaa kaikki alkuperäisen sovelluksen työkalut myös Bing Mapsin APIlla. Iso osa työstä koski polygonien piirtämistä kartalle sekä piirrettyjen polygonien muokkausta. Työ toteutettiin JavaScript-ohjelmointikielellä ja Bing Mapsin AJAX Control versio 7:llä. Työn teko aloitettiin tutkimalla Bing Mapsin APIn ja Google Mapsin APIn eroja ja miettimällä, miten Google Mapsissa käytetyt ominaisuudet toteutettaisiin Bing Mapsissa. Ongelmien ratkeamisen myötä Bing Mapsin ominaisuuksia lisättiin alkuperäiseen sovellukseen. Kaikki alkuperäisen Google Mapsin APIa käyttävän sovelluksen toiminnot saatiin toteutettua myös Bing Mapsin APIlla. Suurin osa toiminnoista toimi erittäin hyvin, mutta osassa toiminnoissa oli pieniä ongelmia. Ongelmat olivat kuitenkin suurimmaksi osaksi täysin visuaalisia virheitä, eivätkä ne estäneet sovelluksen käyttämistä

Rules and Strategies Implementation of RedBot Competition

Tato práce se zabývá vytvořením zadání programovací soutěže RedBot. Jedná se o soutěž pro studentské týmy, pořádanou společností RedHat. Práce popisuje postup tvorby zadání soutěže a implementaci vyhodnocovacího serveru, který bude sloužit k vyhodnocení soutěže. Tato práce se dále zabývá implementací vizualizační utility k zobrazení průběhu hry a implementací obslužných rutin, které mohou soutěžící využít pro rychlejší tvorbu strategií.The bachelor thesis deals with creating rules of RedBot programming competition. This competition is organized by RedHat company and is designed for students' teams. The objective of thesis is to describe process of making competition rules and implementation of evaluation server for assessing results of the competition. The other objective is to implement visualization utility for view of the game and implementation of basic routine which is useful for faster strategy creation.

Multivariate Techniques for Identifying Diffractive Interactions at the LHC

31 pages, 14 figures, 11 tablesClose to one half of the LHC events are expected to be due to elastic or inelastic diffractive scattering. Still, predictions based on extrapolations of experimental data at lower energies differ by large factors in estimating the relative rate of diffractive event categories at the LHC energies. By identifying diffractive events, detailed studies on proton structure can be carried out. The combined forward physics objects: rapidity gaps, forward multiplicity and transverse energy flows can be used to efficiently classify proton-proton collisions. Data samples recorded by the forward detectors, with a simple extension, will allow first estimates of the single diffractive (SD), double diffractive (DD), central diffractive (CD), and non-diffractive (ND) cross sections. The approach, which uses the measurement of inelastic activity in forward and central detector systems, is complementary to the detection and measurement of leading beam-like protons. In this investigation, three different multivariate analysis approaches are assessed in classifying forward physics processes at the LHC. It is shown that with gene expression programming, neural networks and support vector machines, diffraction can be efficiently identified within a large sample of simulated proton-proton scattering events. The event characteristics are visualized by using the self-organizing map algorithm.Peer reviewe

Luminosity monitors at the LHC

We study the theoretical accuracy of various methods that have been proposed to measure the luminosity of the LHC pp collider, as well as for Run II of the Tevatron p barp collider. In particular we consider methods based on (i) the total and forward elastic data, (ii) lepton-pair production and (iii) W and Z production.Comment: 23 pages, Latex, 9 figure