{"id":{"repo_id":"heid-diss","oai_identifier":"oai:archiv.ub.uni-heidelberg.de:3084"},"canonical_url":"https://search.dev.ndltd.org/etd/heid-diss/oai:archiv.ub.uni-heidelberg.de:3084","repository":{"repo_id":"heid-diss","name":"Universität Heidelberg","base_url":"http://archiv.ub.uni-heidelberg.de/volltextserver/cgi/oai2"},"display":{"title":"Soft diffractive high energy scattering and form factors in nonperturbative QCD","abstract":"In this work we study soft high energy reactions in the framework of nonperturbative models. Using a functional integral approach we derive the scattering amplitudes, which are governed by expectation values of light-like Wegner-Wilson loops and lines, which then are then evaluated in the model of the stochastic vacuum. We describe mesons in a simple quark-antiquark picture, for baryons we assume a quark-diquark structure, as hadronic wave functions we apply a Wirbel-Stech-Bauer ansatz. In the following we calculate integrated and differential cross sections from the scattering amplitudes, as well for elastic and diffractive proton-proton as for proton-pion scattering at high centre of mass energies and small momentum transfers and compare to experimental data. Depending on the symmetry of the respective final state we get either C=P=+1 (pomeron) oder C=P=-1 (odderon) exchange. Furthermore we calculate the isovector form factors of the proton and the pion at space-like momentum transfers. In the final chapter we use a dispersion approach to calculate the pion form factor at time-like momentum transfers and determine the masses and coupling constants of the rho- and omega-mesons from a comparison to experimental data.","abstract_html":"In this work we study soft high energy reactions in the framework of nonperturbative models. Using a functional integral approach we derive the scattering amplitudes, which are governed by expectation values of light-like Wegner-Wilson loops and lines, which then are then evaluated in the model of the stochastic vacuum. We describe mesons in a simple quark-antiquark picture, for baryons we assume a quark-diquark structure, as hadronic wave functions we apply a Wirbel-Stech-Bauer ansatz. In the following we calculate integrated and differential cross sections from the scattering amplitudes, as well for elastic and diffractive proton-proton as for proton-pion scattering at high centre of mass energies and small momentum transfers and compare to experimental data. Depending on the symmetry of the respective final state we get either C=P=+1 (pomeron) oder C=P=-1 (odderon) exchange. Furthermore we calculate the isovector form factors of the proton and the pion at space-like momentum transfers. In the final chapter we use a dispersion approach to calculate the pion form factor at time-like momentum transfers and determine the masses and coupling constants of the rho- and omega-mesons from a comparison to experimental data.","abstract_has_math":false,"creators":["Paulus, Timo"],"institution":"Universität Heidelberg","degree_name":null,"degree_level":"thesis.doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Nachtmann, Otto"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2002,"date_issued":"2002-12-16","date_published":"2002-12-16","updated_at":"2026-07-24T02:29:25Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://www.ub.uni-heidelberg.de/archiv/3084","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Nachtmann, Otto"]},{"key":"dc:creator","label":"Author","values":["Paulus, Timo"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:publisher","label":"Institution","values":["Universitätsbibliothek Heidelberg"]},{"key":"dc:type","label":"Dc Type","values":["doctoralThesis"]},{"key":"thesis:degree_level","label":"Degree Level","values":["thesis.doctoral"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Universität Heidelberg"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["In this work we study soft high energy reactions in the framework of nonperturbative models. Using a functional integral approach we derive the scattering amplitudes, which are governed by expectation values of light-like Wegner-Wilson loops and lines, which then are then evaluated in the model of the stochastic vacuum. We describe mesons in a simple quark-antiquark picture, for baryons we assume a quark-diquark structure, as hadronic wave functions we apply a Wirbel-Stech-Bauer ansatz. In the following we calculate integrated and differential cross sections from the scattering amplitudes, as well for elastic and diffractive proton-proton as for proton-pion scattering at high centre of mass energies and small momentum transfers and compare to experimental data. Depending on the symmetry of the respective final state we get either C=P=+1 (pomeron) oder C=P=-1 (odderon) exchange. Furthermore we calculate the isovector form factors of the proton and the pion at space-like momentum transfers. In the final chapter we use a dispersion approach to calculate the pion form factor at time-like momentum transfers and determine the masses and coupling constants of the rho- and omega-mesons from a comparison to experimental data.","In der vorliegenden Arbeit untersuchen wir weiche Hochenergie-Reaktionen im Rahmen nichtperturbativer Modelle. Dazu verwenden wir ein auf einem Funktionalintegral-Ansatz beruhendes Modell und leiten die Streuamplituden her, deren wesentlicher Bestandteil Erwartungswerte von lichtartigen Wegner-Wilson Schleifen und Linien sind, die dann im Modell des stochastischen Vakuums berechnet werden. Mesonen beschreiben wir in einem einfachen Quark-Antiquark Bild, fr Baryonen nehmen wir eine Quark-Diquark Struktur an, als Hadron-Wellenfunktionen verwenden wir einen Wirbel-Stech-Bauer Ansatz. Aus den Streuamplituden berechnen wir integrierte und differentielle Wirkungsquerschnitte sowohl fr elastische und diffraktive Proton-Proton als auch fr Proton-Pion Streuung bei hohen Schwerpunktsenergien und kleinen Impulsbertragen und vergleichen mit experimentellen Daten. Abhangig von der Symmetrie des jeweiligen Endzustandes erhalten wir entweder C=P=+1 (Pomeron) oder C=P=-1 (Odderon) Austausch. Des weiteren berechnen wir im Rahmen des Modells die Isovektor-Formfaktoren des Protons und des Pions bei raumartigen Impulsbertragen. Im abschliessenden Kapitel verwenden wir einen Dispersionsrelations-Ansatz zur Berechnung des Pion Formfaktors bei zeitartigen Impulsbertragen. Aus dem Vergleich mit experimentellen Daten bestimmen wir die Massen und Kopplungskonstanten der rho- und omega-Mesonen."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Soft diffractive high energy scattering and form factors in nonperturbative QCD","Weiche diffraktive Hochenergiestreuung und Formfaktoren in nichtperturbativer QCD"]}]}],"canonical_facts":{"dc:contributor":["Nachtmann, Otto"],"dc:creator":["Paulus, Timo"],"dc:description.abstract":["In this work we study soft high energy reactions in the framework of nonperturbative models. Using a functional integral approach we derive the scattering amplitudes, which are governed by expectation values of light-like Wegner-Wilson loops and lines, which then are then evaluated in the model of the stochastic vacuum. We describe mesons in a simple quark-antiquark picture, for baryons we assume a quark-diquark structure, as hadronic wave functions we apply a Wirbel-Stech-Bauer ansatz. In the following we calculate integrated and differential cross sections from the scattering amplitudes, as well for elastic and diffractive proton-proton as for proton-pion scattering at high centre of mass energies and small momentum transfers and compare to experimental data. Depending on the symmetry of the respective final state we get either C=P=+1 (pomeron) oder C=P=-1 (odderon) exchange. Furthermore we calculate the isovector form factors of the proton and the pion at space-like momentum transfers. In the final chapter we use a dispersion approach to calculate the pion form factor at time-like momentum transfers and determine the masses and coupling constants of the rho- and omega-mesons from a comparison to experimental data.","In der vorliegenden Arbeit untersuchen wir weiche Hochenergie-Reaktionen im Rahmen nichtperturbativer Modelle. Dazu verwenden wir ein auf einem Funktionalintegral-Ansatz beruhendes Modell und leiten die Streuamplituden her, deren wesentlicher Bestandteil Erwartungswerte von lichtartigen Wegner-Wilson Schleifen und Linien sind, die dann im Modell des stochastischen Vakuums berechnet werden. Mesonen beschreiben wir in einem einfachen Quark-Antiquark Bild, fr Baryonen nehmen wir eine Quark-Diquark Struktur an, als Hadron-Wellenfunktionen verwenden wir einen Wirbel-Stech-Bauer Ansatz. Aus den Streuamplituden berechnen wir integrierte und differentielle Wirkungsquerschnitte sowohl fr elastische und diffraktive Proton-Proton als auch fr Proton-Pion Streuung bei hohen Schwerpunktsenergien und kleinen Impulsbertragen und vergleichen mit experimentellen Daten. Abhangig von der Symmetrie des jeweiligen Endzustandes erhalten wir entweder C=P=+1 (Pomeron) oder C=P=-1 (Odderon) Austausch. Des weiteren berechnen wir im Rahmen des Modells die Isovektor-Formfaktoren des Protons und des Pions bei raumartigen Impulsbertragen. Im abschliessenden Kapitel verwenden wir einen Dispersionsrelations-Ansatz zur Berechnung des Pion Formfaktors bei zeitartigen Impulsbertragen. Aus dem Vergleich mit experimentellen Daten bestimmen wir die Massen und Kopplungskonstanten der rho- und omega-Mesonen."],"dc:format.medium":["application/pdf"],"dc:publisher":["Universitätsbibliothek Heidelberg"],"dc:title":["Soft diffractive high energy scattering and form factors in nonperturbative QCD","Weiche diffraktive Hochenergiestreuung und Formfaktoren in nichtperturbativer QCD"],"dc:type":["doctoralThesis"],"thesis:degree_level":["thesis.doctoral"],"thesis:institution_name":["Universität Heidelberg"]},"updated_at":"2026-07-24T02:29:25Z"}