{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/62649"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/62649","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Applying SCET to parton showers","abstract":"In this thesis we study corrections to parton showers in the context of soft collinear effective theory (SCET). Monte Carlo event generators like Pythia or Herwig are heavily used by experimentalists to simulate events and they are indispensable tools to make exclusive theoretical predictions. They are based on a leading log parton shower algorithm that allows to resum the dominant contributions in the soft and collinear radiation. In this work we construct a framework to classify corrections to the parton shower that can be used to systematically improve event generators. We formulate parton showers as a standard matching procedure between a tower of soft collinear effective field theories called SCETi. We find two different kinds of corrections: hard-scattering corrections and jet-structure corrections. To relate these different effective field theories we make use of an important symmetry of SCET, called reparametrization invariance. In order to systematically study this symmetry, we construct operators that are invariant under reparametrization and we use them to find a minimal basis of operators that are homogeneous in the power counting. Complete basis of operators are constructed for pure glue operators for deep inelasting scattering at twist-4, for production of two and three jets from e+e- and for production of two jets via gluon fusion.","abstract_html":"In this thesis we study corrections to parton showers in the context of soft collinear effective theory (SCET). Monte Carlo event generators like Pythia or Herwig are heavily used by experimentalists to simulate events and they are indispensable tools to make exclusive theoretical predictions. They are based on a leading log parton shower algorithm that allows to resum the dominant contributions in the soft and collinear radiation. In this work we construct a framework to classify corrections to the parton shower that can be used to systematically improve event generators. We formulate parton showers as a standard matching procedure between a tower of soft collinear effective field theories called SCETi. We find two different kinds of corrections: hard-scattering corrections and jet-structure corrections. To relate these different effective field theories we make use of an important symmetry of SCET, called reparametrization invariance. In order to systematically study this symmetry, we construct operators that are invariant under reparametrization and we use them to find a minimal basis of operators that are homogeneous in the power counting. Complete basis of operators are constructed for pure glue operators for deep inelasting scattering at twist-4, for production of two and three jets from e+e- and for production of two jets via gluon fusion.","abstract_has_math":false,"creators":["Marcantonini, Claudio"],"institution":"Massachusetts Institute of Technology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Massachusetts Institute of Technology. Dept. of Physics.","school":null,"contributors":[],"advisors":["Iain W. Stewart."],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010","date_published":"2010","updated_at":"2026-07-22T22:22:11Z","subjects":["Physics."],"languages":["eng"],"rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1721.1/62649","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Iain W. Stewart."]},{"key":"dc:contributor.department","label":"Department","values":["Massachusetts Institute of Technology. Dept. of Physics."]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Massachusetts Institute of Technology. Dept. of Physics."]},{"key":"dc:creator","label":"Author","values":["Marcantonini, Claudio"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2011-05-09T15:14:10Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2011-05-09T15:14:10Z"]},{"key":"dc:date.issued","label":"Date","values":["2010"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Physics."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1721.1/62649"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2010.","Cataloged from PDF version of thesis.","Includes bibliographical references (p. 219-225)."]},{"key":"dc:description.abstract","label":"Abstract","values":["In this thesis we study corrections to parton showers in the context of soft collinear effective theory (SCET). Monte Carlo event generators like Pythia or Herwig are heavily used by experimentalists to simulate events and they are indispensable tools to make exclusive theoretical predictions. They are based on a leading log parton shower algorithm that allows to resum the dominant contributions in the soft and collinear radiation. In this work we construct a framework to classify corrections to the parton shower that can be used to systematically improve event generators. We formulate parton showers as a standard matching procedure between a tower of soft collinear effective field theories called SCETi. We find two different kinds of corrections: hard-scattering corrections and jet-structure corrections. To relate these different effective field theories we make use of an important symmetry of SCET, called reparametrization invariance. In order to systematically study this symmetry, we construct operators that are invariant under reparametrization and we use them to find a minimal basis of operators that are homogeneous in the power counting. Complete basis of operators are constructed for pure glue operators for deep inelasting scattering at twist-4, for production of two and three jets from e+e- and for production of two jets via gluon fusion."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph.D."]},{"key":"dc:title","label":"Title","values":["Applying SCET to parton showers"]}]}],"canonical_facts":{"dc:contributor.advisor":["Iain W. Stewart."],"dc:contributor.department":["Massachusetts Institute of Technology. Dept. of Physics."],"dc:contributor.other":["Massachusetts Institute of Technology. Dept. of Physics."],"dc:creator":["Marcantonini, Claudio"],"dc:date.accessioned":["2011-05-09T15:14:10Z"],"dc:date.available":["2011-05-09T15:14:10Z"],"dc:date.issued":["2010"],"dc:description":["Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2010.","Cataloged from PDF version of thesis.","Includes bibliographical references (p. 219-225)."],"dc:description.abstract":["In this thesis we study corrections to parton showers in the context of soft collinear effective theory (SCET). Monte Carlo event generators like Pythia or Herwig are heavily used by experimentalists to simulate events and they are indispensable tools to make exclusive theoretical predictions. They are based on a leading log parton shower algorithm that allows to resum the dominant contributions in the soft and collinear radiation. In this work we construct a framework to classify corrections to the parton shower that can be used to systematically improve event generators. We formulate parton showers as a standard matching procedure between a tower of soft collinear effective field theories called SCETi. We find two different kinds of corrections: hard-scattering corrections and jet-structure corrections. To relate these different effective field theories we make use of an important symmetry of SCET, called reparametrization invariance. In order to systematically study this symmetry, we construct operators that are invariant under reparametrization and we use them to find a minimal basis of operators that are homogeneous in the power counting. Complete basis of operators are constructed for pure glue operators for deep inelasting scattering at twist-4, for production of two and three jets from e+e- and for production of two jets via gluon fusion."],"dc:description.degree":["Ph.D."],"dc:identifier.uri":["http://hdl.handle.net/1721.1/62649"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Physics."],"dc:title":["Applying SCET to parton showers"],"dc:type":["Thesis"]},"updated_at":"2026-07-22T22:22:11Z"}