Research Eddi De Wolf

Abstract

The Compact Muon Solenoid experiment has put emphasis on the detection and identification of muons; the only penetrating charged particle we know. At the LHC, the bunch crossing frequency will be 40 MHz, which, at the nominal luminosity of 10^34 cm-2s-1, leads to 800 million proton-proton collisions per second. Every 25 nsec some 1000 particles emerge from the interaction point into the CMS spectrometer. In less than 3 microsec a first level trigger has to reduce this rate to 100 kHz without losing potentially interesting collisions requiring further analysis. This task, without which research at the LHC would be impossible, relies heavily on the muon detection system. The construction of the forward muon RPC system for the CMS phase 1 detector is completed and consists of 432 chambers. All gas gaps have been produced and tested in Seoul where a gas gap production facility has been set up for this project. It is an alternative to the Italian company GT that up to then had the world monopoly for RPC gas gap production and delivered gaps to L3, Babar, ATLAS and the CMS barrel. Station 1 (144 RPC's) has been produced and tested at CERN with the help of Chinese manpower. Stations 2 and 3 (288 RPC's) are assembled in Islamabad and retested at CERN. For the final testing of endcap RPC's, a large area cosmic hodoscope has been built at CERN in which 10 chambers can be tested together. This infrastructure will remain operational until completion of the entire system. Today all 432 RPC detectors of the initial system have been installed on the endcap yokes. The completion of the forward RPC system for CMS phase 2 will require 288 extra chambers for the |eta|<1.6 region and 180 RPC's for the region 1.6 <eta< 2.1. Production of gas gaps will further proceed in Seoul while chamber assembly would be performed in the other participating institutes and possibly also in Belgium. The final testing of the detectors would be concentrated in the CERN cosmic hodoscope. As mentioned before the total cost for the completion of the CMS forward RPC system is estimated to be 6 MCHF and an equal sharing among the participants is envisaged resulting in 1MCHF for the Belgian partners. It is proposed that 160 RPC chambers would be assembled in Ghent and Brussels, while Antwerp will concentrate more on the front end read out electronics.

Researcher(s)

• Promoter: De Wolf Eddi
• Co-promoter: Van Remortel Nick

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Recent precision measurements of the top quark and W-boson masses at the Tevatron collider, Fermilab, USA, imply the existence of a relatively light Higgs boson with a mass less than 144 GeV at 95% C.L. The search for a light to intermediate mass Higgs boson is now of top priority in the Tevatron physics program (recently extended until end 2009), and is one of the main motivations for the construction of the LHC collider at CERN, which begins its operations in the spring of 2008. For masses below 144 GeV, the Higgs decays with 98% probability to a pair of b-quarks, making its separation from background processes very difficult at the Tevatron. The increased centre-of-mass energy and luminosity of the LHC will overcome some of these problems by allowing more stringent selections and/or the study of rare decays and by opening a range of new Higgs production mechanisms that have smaller cross sections at the Tevatron. The latter will be used as main strategy in this proposal where a Higgs discovery group will systematically explore the Higgs boson mass range between 114-135 GeV, by using data collected by the CMS experiment at the LHC collider at CERN, Geneva, Switzerland. The project's focus is the distinct topology where the Higgs boson decays into a pair of b quarks and is accompanied by the production and decays of two top quarks: ttH->bbWWbb. We will investigate mainly the final states in which at least one W boson decays leptonically. The proposed research complements ongoing activities at the particle physics group of the University of Antwerpen, where a Higgs boson search at intermediate to High Higgs masses is conducted in the dominant decay mode H->WW, using final states in which both W's decay leptonically. Both projects combined will cover the whole Higgs mass region which is kinematically accessible by the LHC accelerator.

Researcher(s)

• Promoter: Van Remortel Nick
• Co-promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The project is part of the FWO Big Science funding which allows participation in large-scale international experiments at CERN and elsewhere. The funding covers our participation to the CMS experiment at the LHC in CERN in terms of logistic personnel support, contributions to the 'Maintenance and Operation' of the CMS detector and the development of local GRID infrastructure..

Researcher(s)

• Promoter: De Wolf Eddi
• Promoter: Van Mechelen Pierre
• Co-promoter: Van Mechelen Pierre

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Fundamental interactions include electroweak forces, strong interactions, and gravity. Their study aims at unraveling Nature's mechanisms at their most intimate level, including the origin of the Universe, through work at the boundary of present knowledge. Such knowledge is sought trough tighter collaboration between all Belgian theorists and experimentalists active in the field of fundamental interactions.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The Large Hadron Collider, LHC, will start operating at CERN in 2007. The Particle Physics group of the University of Antwerp is a participant in the CMS experiment. Major physics goals are the understanding of the electroweak symmetry breaking, the search for signals of 'new physics' such as supersymmetry or large extra dimensions, and the study of Quantum Chromodynamics processes. The Forward Physics program, the subject of this proposal, aims at enhancing the capabilities of the CMS experiment for diffractive and forward physics. The project will concentrate on the use of forward proton detection as a unique means to discover new physics at the LHC.

Researcher(s)

• Promoter: De Wolf Eddi
• Promoter: Van Mechelen Pierre
• Co-promoter: De Roeck Albert
• Co-promoter: Van Mechelen Pierre

Research team(s)

• Particle Physics Group

Project website

Project type(s)

• Research Project

Abstract

This project aims to analyse the data that will collected by the CMS detector at the LHC accelerator. It consist mainly of the research of the top quark and so-called "diffraction and forward physics". To realise this a contribution will be made to the development of a Belgian TIER-2 GRID computing centre.

Researcher(s)

• Promoter: Van Mechelen Pierre
• Co-promoter: De Roeck Albert
• Co-promoter: De Wolf Eddi
• Co-promoter: Van Remortel Nick

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: De Wolf Eddi
• Co-promoter: Van Mechelen Pierre

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The primary objective of the project is the collection and analysis of data acquired from 2005 to 2007 with the H1 detector and the VFPS in order to study processes of the type e + p ¿ e p X, with jets or charmed particles in the final state. Diffractive dissociation in electron-proton collisions, in particular in association with final states containing jets or heavy quarks, can be described in Quantum Chromodynamics (QCD), the theory of the strong force. The phenomenon of diffraction is connected to fundamental properties of the strong force, including the confinement of quarks inside hadrons. The proposed measurements will provide novel information on the (diffractive) quark and gluon content of the photon and proton and further allow to test a variety of theoretical models and higher order QCD calculations. The project requires expertise on both the analysis of jets and of diffractive interactions, on the operation of the VFPS and on theoretical QCD calculations. In this respect the Prague and Antwerp groups are complementary and benefit both from a close collaboration. To achieve the project goals, regular exchanges between the institutes in Prague and Antwerp and the DESY laboratory in Hamburg are needed.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Tsurin Ilya

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Micro Gap Counters are a new kind of detectors for charged particles. They have the following properties: high spatial resolution, large counting rate, radiation resistent. Different parameters of these detectors will be optimised and a large prototype build, consisting of some 70 elementary cells, 10 by 10 cm each.

Researcher(s)

• Promoter: De Wolf Eddi
• Co-promoter: Van Mechelen Pierre

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The present proposal centers around the 'Very Forward Proton Spectrometer' (VFPS) project, a new detector to be commissioned this year for the H1 experiment at DESY in Hamburg. The Belgian groups, and the UIA in particular, have initiated and taken major responsabilities in this project. The goal of the project is to perform refined second-generation experimental studies of the phenomenon of diffractive dissociation in deep-inelastic electron/positron-proton collisions at the HERA collider.A primary objective is the analysis of the first data to be collected in 2004 with the VFPS. The focus will be on the study of diffractive jet production and charmed particle production with a directly tagged proton in the reaction positron + proton ? X + proton. Jet production and heavy quark production can be theoretically described in Quantumchromodynamics (QCD), the theory of the strong force. The measurements to be performed will provide novel information on the quark and gluon composition of the (virtual) photon and of the Pomeron and further allow to test a variety of theoretical models, in particular higher-order perturbative QCD calculations.Technically, the project requires i) implementation of the simulation- and reconstruction software of the VFPS system, ii) development of techniques to calibrate the detector in a true collision environment, in real-time. These tasks will be performed by the UIA group, with the help of software specialists from the Prague group.For the analysis of the data, leading to publications, the existing rich expertise of the Prague group in the study of jet production will be of essential value and complement the know-how of the Flemish partner.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Recently, the study of diffractive processes has known a large renewed interest. The diverse experimental programmes of current hadron accelerators such as HERA and TEVATRON offer, together with future machines such as the LHC at CERN, a great new challenge both in theoretical and experimental particle physics research. Diffractive processes can be considered as a sub-class of inelastic scattering processes, where one of the colliding particles survives the interaction: A + B à A + X. The H1 experiment of the German research centre DESY, situated in Hamburg, to which the particle physics group of the UA is connected, has seen a considerable upgrade last year. The very forward proton spectrometer (VFPS), co-developed by our group and partly financed by the FWO, is a considerable part of this upgrade. The VFPS detector is complementary to the existing system of H1 and has in contrast to the existing spectrometer a very large acceptance and the possibility of precise calibration. Numerous diffractive processes, such as di-jet production, open charm and vector meson production, have been measured with the existing H1 setup, however with limited statistics and large background contamination from proton-dissociation processes. The new VFPS detector will contribute, in combination with an increased luminosity of the HERA accelerator, to a more precise measurement of these processes. It is therefore expected that, in parallel with theoretical progress, new insights will be gained in the dynamics of diffraction within the framework of the quantum-chromodynamics formalism. The commisioning of the new apparatus and the collection of new data is planned before the end of 2003.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Van Remortel Nick

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

This project aims to contribute to the understanding of diffractive deep-inelastic scattering in two ways: 1. Using the large data sample acquired by the H1 experiment in DESY from 1996 to 2000, a new detailed analysis will be performed of the hadronic final state in diffractive DIS. The much larger number of events will allow a more precise and more differential study of final state characteristics like thrust, energy flow and the multiplicity structure, than previously possible. More specifically, it should now be possible to study the hadronic final state as a function of the photon virtuality and/or the momentum fraction from the pomeron carried by the struck parton. Theory predicts different contributions to the diffractive cross section as a function of these variables. 2. The H1 detector is presently not capable to detect the diffractively scattered proton. Therefore a proposal is being prepared by several member institutes of the H1 collaboration, to install a new proton spectrometer 220~m from the H1 detector, downstream the proton beam. The contribution to this project consists of the study of a new prototype of scintillating fibre detector and the development of reconstruction and calibration software for this future proton spectrometer.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Anthonis Tinne

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The present project involves the study of the fundamental constituents of matter, and their interactions. The Large Hadron Collider at CERN, operational in 2006, opens exciting perspectives for the discovery of the Brout-Englert-Higgs boson, possible supersymmetric particles and evidence for extra space-time dimensions. The purpose of the present initiative is to increase the collaboration between the belgian research teams in theoretical and experimental particle physics with the aim of contributing in a significant way to one of the most challenging and exciting chapters of modern fundamental research.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The subject of this project is the evolution of the structure and interaction of the exchanged photon in electron-proton collisions, as a function of the photon virtuality. To that and the multiparticle final state in photoproduction and deep-inelastic interactions is studied. The particle and transverse energy density, the local and long- range particle correlations and the transverse momentum distribution will provide insight in the dynamica of photon-proton collisions.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Van Mechelen Pierre

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Study of particle correlations in high-energy electron-proton collisions at the HERA collider in DESY, and in electron-positron annihilations at the LEP collider in CERN.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Sarkysyan-Grinbaum Edward

Research team(s)

Project type(s)

• Research Project

Abstract

The project aims at experimental measurement and theoretical understanding of various correlation phenomena (Bose-Einstein, Color reconnection) in the production of W-W pairs in electron-positron annihilations at LEPII.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The project aims at experimental measurement and theoretical understanding of various correlation phenomena (Bose-Einstein, Color reconnection) in the production of W-W pairs in electron-positron annihilations at LEP II.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

This project aims to contribute to the understanding of diffractive deep-inelastic scattering in two ways: 1. Using the large data sample acquired by the H1 experiment in DESY from 1996 to 2000, a new detailed analysis will be performed of the hadronic final state in diffractive DIS. The much larger number of events will allow a more precise and more differential study of final state characteristics like thrust, energy flow and the multiplicity structure, than previously possible. More specifically, it should now be possible to study the hadronic final state as a function of the photon virtuality and/or the momentum fraction from the pomeron carried by the struck parton. Theory predicts different contributions to the diffractive cross section as a function of these variables. 2. The H1 detector is presently not capable to detect the diffractively scattered proton. Therefore a proposal is being prepared by several member institutes of the H1 collaboration, to install a new proton spectrometer 220~m from the H1 detector, downstream the proton beam. The contribution to this project consists of the study of a new prototype of scintillating fibre detector and the development of reconstruction and calibration software for this future proton spectrometer.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Anthonis Tinne

Research team(s)

Project type(s)

• Research Project

Abstract

A new very forward proton spectrometer (VFPS) with large acceptance will be built, to be instalied in the proton bea.m of the Hl eXperiment after the luminasity upgrade in 2000. The spectrometer, located ~t 220 m downstream of the interaction point is based on the Roman Pot technique. It consists of two stations situa.ted in the cold se<.tion of the beam-line. It will allow study of diffraction dissociation processes in deep-inelastic ep scattering with unprecedented acceptance and in a kinematic region never explored befare.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The research comprises experimental studies of hadron-hadron and lepton-hadron collisions at the highest energies (> 100 GeV/c) performed at particles accelerators at CERN (Geneva), Serpukhov (USSR) and Fermilab (USA). Results are compared with or interpreted in terms of the theories such as Quantumchromodynamics and the Weinberg-Salam theory of the electro-weak interaction.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

This project aims to contribute to the understanding of diffractive deep-inelastic scattering in two ways: 1. Using the large data sample acquired by the H1 experiment in DESY from 1996 to 2000, a new detailed analysis will be performed of the hadronic final state in diffractive DIS. The much larger number of events will allow a more precise and more differential study of final state characteristics like thrust, energy flow and the multiplicity structure, than previously possible. More specifically, it should now be possible to study the hadronic final state as a function of the photon virtuality and/or the momentum fraction from the pomeron carried by the struck parton. Theory predicts different contributions to the diffractive cross section as a function of these variables. 2. The H1 detector is presently not capable to detect the diffractively scattered proton. Therefore a proposal is being prepared by several member institutes of the H1 collaboration, to install a new proton spectrometer 220~m from the H1 detector, downstream the proton beam. The contribution to this project consists of the study of a new prototype of scintillating fibre detector and the development of reconstruction and calibration software for this future proton spectrometer.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Anthonis Tinne

Research team(s)

Project type(s)

• Research Project

Abstract

This project aims to contribute to the understanding of diffractive deep-inelastic scattering in two ways: 1. Using the large data sample acquired by the H1 experiment in DESY from 1996 to 2000, a new detailed analysis will be performed of the hadronic final state in diffractive DIS. The much larger number of events will allow a more precise and more differential study of final state characteristics like thrust, energy flow and the multiplicity structure, than previously possible. More specifically, it should now be possible to study the hadronic final state as a function of the photon virtuality and/or the momentum fraction from the pomeron carried by the struck parton. Theory predicts different contributions to the diffractive cross section as a function of these variables. 2. The H1 detector is presently not capable to detect the diffractively scattered proton. Therefore a proposal is being prepared by several member institutes of the H1 collaboration, to install a new proton spectrometer 220~m from the H1 detector, downstream the proton beam. The contribution to this project consists of the study of a new prototype of scintillating fibre detector and the development of reconstruction and calibration software for this future proton spectrometer.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

Micro Gap Counters are a new kind of detectors for charged particles. They have the following properties: high spatial resolution, large counting rate, radiation resistent. Different parameters of these detectors will be optimised and a large prototype build, consisting of some 70 elementary cells, 10 by 10 cm each.

Researcher(s)

• Promoter: De Wolf Eddi
• Promoter: Verbeure Frans
• Co-promoter: De Wolf Eddi

Research team(s)

• Particle Physics Group

Project type(s)

• Research Project

Abstract

The subject of this project is the evolution of the structure and interaction of the exchanged photon in electron-proton collisions, as a function of the photon virtuality. To that and the multiparticle final state in photoproduction and deep-inelastic interactions is studied. The particle and transverse energy density, the local and long- range particle correlations and the transverse momentum distribution will provide insight in the dynamica of photon-proton collisions.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: Van Mechelen Pierre

Research team(s)

Project type(s)

• Research Project

Abstract

At the HERA collider in DESY (Hamburg), electron or positrons collide with protons at a centre-of-mass energy of 300 GeV, the highest energy so far achieved for this type of processes. Depending on the `hardness' of the interactions, expressed in terms of the virtuality of the exchanged vector boson, the collisions are classified either as `deep-inelastic' or as `photoproductionÆ reactions. In the latter, the exhanged boson acts as a hadron and its interactions with the target proton are essentially non-perturbative. In deep-inelastic processes, the exchanged boson acts as an esemble of quarks and gluons and can be described by perturbation theory in quantumchromodynamics (QCD). In this project, the H1 detector at HERA is used to study experimentally the properties of hadronic multiparticle final states as a function of the `hardnessÆ of the interaction. It is hoped that these data provide unique information on the transition from the perturbative to the non-perturbative regime of QCD.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

Interactions between elementary particles at high energies are studied in 2 large electronic experiments: 1. e+e-interactions at energies around the Z mass (91 GeV) at the LEP collider at CERN with the DELPHI detector. 2. e-p interactions in colliding beams of 30 resp 820 GeV at the HERA collider at DESY, with the H1 detector.

Researcher(s)

• Promoter: Verbeure Frans
• Co-promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The research comprises experimental studies of hadron-hadron and lepton-hadron collisions at the highest energies (> 100 GeV/c) performed at particles accelerators at CERN (Geneva), Serpukhov (USSR) and Fermilab (USA). Results are compared with or interpreted in terms of the theories such as Quantumchromodynamics and the Weinberg-Salam theory of the electro-weak interaction.

Researcher(s)

• Promoter: De Wolf Eddi
• Fellow: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

Micro Gap Counters are a new kind of detectors for charged particles. They have the following properties: high spatial resolution, large counting rate, radiation resistent. Different parameters of these detectors will be optimised and a large prototype build, consisting of some 70 elementary cells, 10 by 10 cm each.

Researcher(s)

• Promoter: Verbeure Frans
• Co-promoter: De Wolf Eddi
• Co-promoter: Van Landuyt Joseph

Research team(s)

Project type(s)

• Research Project

Abstract

Interactions between elementary particles at high energies are studied in 2 large electronic experiments: 1. e+e-interactions at energies around the Z mass (91 GeV) at the LEP collider at CERN with the DELPHI detector. 2. e-p interactions in colliding beams of 30 resp 820 GeV at the HERA collider at DESY, with the H1 detector.

Researcher(s)

• Promoter: Verbeure Frans
• Co-promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

3 Belgian groups have built a cylindrical proportional chamber for the H1 detector at HERA, Hamburg. This project aims at the running and full exploitation of the detector for a study of the deep structure of the protons

Researcher(s)

• Promoter: Verbeure Frans
• Co-promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The research comprises experimental studies of hadron-hadron and lepton-hadron collisions at the highest energies (> 100 GeV/c) performed at particles accelerators at CERN (Geneva), Serpukhov (USSR) and Fermilab (USA). Results are compared with or interpreted in terms of the theories such as Quantumchromodynamics and the Weinberg-Salam theory of the electro-weak interaction

Researcher(s)

• Promoter: Verbeure Frans
• Fellow: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

Hadronic final states in deep-inelastic electron-proton collisions are studied with respect to particle composition, fluctuations and correlations, jet productie en QCD coherence effects.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The projects objective is an experimental study of second-and higher-order correlations among hadrons produced in deep inelastic e p collisions in the H1 experiment at HERA (DESY, Hamburg). This could reveal evidence for strong non-linear collective effects in quantumchromodynamics.

Researcher(s)

• Promoter: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project

Abstract

The research comprises experimental studies of hadron-hadron and lepton-hadron collisions at the highest energies (> 100 GeV/c) performed at particles accelerators at CERN (Geneva), Serpukhov (USSR) and Fermilab (USA). Results are compared with or interpreted in terms of the theories such as Quantumchromodynamics and the Weinberg-Salam theory of the electro-weak interaction.

Researcher(s)

• Promoter: Verbeure Frans
• Fellow: De Wolf Eddi

Research team(s)

Project type(s)

• Research Project