{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/86470"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/86470","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Predictions for the Decay of the Higgs Boson to Bottom Quarks to Third Order in QCD","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["Mondini, Roberto; 0000-0003-2507-0008"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Williams, Ciaran","Physics"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-02-21T17:22:44Z","date_published":"2025-02-21T17:22:44Z","updated_at":"2026-07-27T19:05:32Z","subjects":["particle physics","theoretical physics"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/86470","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Williams, Ciaran","Physics"]},{"key":"dc:creator","label":"Author","values":["Mondini, Roberto; 0000-0003-2507-0008"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2025-02-21T17:22:44Z","2020"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["particle physics","theoretical physics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/86470"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","In this dissertation we present a fully-differential calculation of the decay of the Higgs boson to bottom quarks (H->bb) at next-to-next-to-next-to-leading-order (N3LO) accuracy in QCD. We regulate the infrared divergences present in the calculation at this perturbative order by using the Projection-to-Born technique coupled with the N-jettiness slicing method. In the first part of the dissertation we compute the 1-jettiness soft function at NNLO accuracy. This function is one of the required pieces in order to employ N-jettiness slicing to handle infrared divergences. The calculation uses the known expressions for the emission of one and two soft partons and is performed using a sector-decomposition approach that is spelled out in detail. Results are presented in the form of numerical fits to the 1-jettiness soft function for LHC kinematics (as a function of the angle between the incoming beams and the final-state jet) and for generic kinematics (as a function of three independent angles). In the second part of the dissertation we consider the NNLO corrections to the decay process H->bbj, where j represents additional QCD radiation. In this calculation we treat the bottom quarks as massless and focus on contributions in which the Higgs boson couples directly to bottom quarks through a non-zero Yukawa coupling. We compute the various components needed to construct the NNLO contribution, including an independent calculation of the two-loop amplitudes, and build a Monte Carlo implementation of H->bbj. Finally, in the third part of the dissertation we use the results of the H->bbj calculation to obtain fully-differential predictions for the H->bb decay at N3LO accuracy. We discuss how to combine the Projection-to-Born method with the N-jettiness slicing procedure and extensively validate our methodology. We present exclusive jet rates and differential distributions for jet observables at N3LO using the Durham jet algorithm in the Higgs boson rest frame.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Predictions for the Decay of the Higgs Boson to Bottom Quarks to Third Order in QCD"]}]}],"canonical_facts":{"dc:contributor":["Williams, Ciaran","Physics"],"dc:creator":["Mondini, Roberto; 0000-0003-2507-0008"],"dc:date":["2025-02-21T17:22:44Z","2020"],"dc:description":["Ph.D.","In this dissertation we present a fully-differential calculation of the decay of the Higgs boson to bottom quarks (H->bb) at next-to-next-to-next-to-leading-order (N3LO) accuracy in QCD. We regulate the infrared divergences present in the calculation at this perturbative order by using the Projection-to-Born technique coupled with the N-jettiness slicing method. In the first part of the dissertation we compute the 1-jettiness soft function at NNLO accuracy. This function is one of the required pieces in order to employ N-jettiness slicing to handle infrared divergences. The calculation uses the known expressions for the emission of one and two soft partons and is performed using a sector-decomposition approach that is spelled out in detail. Results are presented in the form of numerical fits to the 1-jettiness soft function for LHC kinematics (as a function of the angle between the incoming beams and the final-state jet) and for generic kinematics (as a function of three independent angles). In the second part of the dissertation we consider the NNLO corrections to the decay process H->bbj, where j represents additional QCD radiation. In this calculation we treat the bottom quarks as massless and focus on contributions in which the Higgs boson couples directly to bottom quarks through a non-zero Yukawa coupling. We compute the various components needed to construct the NNLO contribution, including an independent calculation of the two-loop amplitudes, and build a Monte Carlo implementation of H->bbj. Finally, in the third part of the dissertation we use the results of the H->bbj calculation to obtain fully-differential predictions for the H->bb decay at N3LO accuracy. We discuss how to combine the Projection-to-Born method with the N-jettiness slicing procedure and extensively validate our methodology. We present exclusive jet rates and differential distributions for jet observables at N3LO using the Durham jet algorithm in the Higgs boson rest frame.","**To request an accessible version of the file(s) associated with this item, contact library@buffalo.edu. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.**"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/86470"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["particle physics","theoretical physics"],"dc:title":["Predictions for the Decay of the Higgs Boson to Bottom Quarks to Third Order in QCD"],"dc:type":["Text","Dissertation"]},"updated_at":"2026-07-27T19:05:32Z"}