{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/116285"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/116285","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"RESONANCE in radio frequency sheath admittance in nuclear fusion scenarios","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-15 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-15 without embargo terms","abstract_has_math":false,"creators":["Rezazadeh, Mikhail Xerxes"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Nuclear, Plasma, Radiolgc Engr","degree_department":null,"school":null,"contributors":["Curreli, Davide","Sankaran, Mohan"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-08","date_published":"2022-08","updated_at":"2026-07-22T22:24:56Z","subjects":["Radio frequency","radiofrequency","fusion","nuclear","admittance","resonance"],"languages":["en","eng"],"rights":["Copyright 2022 Mikhail Rezazadeh"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/116285","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Curreli, Davide","Sankaran, Mohan"]},{"key":"dc:creator","label":"Author","values":["Rezazadeh, Mikhail Xerxes"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2022-08","2022-07-21"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Nuclear, Plasma, Radiolgc Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Radio frequency","radiofrequency","fusion","nuclear","admittance","resonance"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2022 Mikhail Rezazadeh"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/116285"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-15 without embargo terms","The student, Mikhail Rezazadeh, accepted the attached license on 2022-07-21 at 14:15.","The student, Mikhail Rezazadeh, submitted this Thesis for approval on 2022-07-21 at 14:23.","This Thesis was approved for publication on 2022-07-21 at 15:48.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18417 on 2022-11-15 at 18:22:03","The next generation of tokamaks (SPARC, ARC, FNSF, DEMO) and several current tokamaks (WEST, etc.) will operate with Ion Cyclotron Resonance Heating (ICRH) as their sole auxiliary heating technique because it transfers power directly to the ions, and it involves the cheapest radio frequency (RF) components. During ICRH operation, RF sheaths form on the ICRH antenna itself, as well as on far-field magnetically-connected surfaces. However, RF sheaths are associated with large hot-spot formation and large impurity emissions. This work presents high-resolution numerical experiments on RF sheaths in nuclear fusion scenarios using hPIC2, a GPU-accelerated hybrid fluid-kinetic particle-in-cell code. The combined data from these experiments was obtained using super computing GPU-accelerated hardware which would require hPIC2 over 10 years of run time, were it running in single-core CPU mode. The experiments reveal a new RF sheath phenomenon which occurs when the radio frequency is on-par with ion cyclotron frequency in an oblique magnetic field. Due to the $1/R$ scaling of the magnetic field in a Tokamak, such cases are possible on a surface on-axis near the bottom of the vacuum chamber, with the precise location, whether on the divertor or the vacuum chamber first wall, dependent on the geometry of the tokamak. The combination of RF and cyclotron frequency are analogous to the classical driven, damped harmonic oscillator, where charge density damps ion admittance. This study shows that the resulting resonance can lead to increased ion flux at the wall and material sputtering."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["RESONANCE in radio frequency sheath admittance in nuclear fusion scenarios"]}]}],"canonical_facts":{"dc:contributor":["Curreli, Davide","Sankaran, Mohan"],"dc:creator":["Rezazadeh, Mikhail Xerxes"],"dc:date":["2022-08","2022-07-21"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-11-15 without embargo terms","The student, Mikhail Rezazadeh, accepted the attached license on 2022-07-21 at 14:15.","The student, Mikhail Rezazadeh, submitted this Thesis for approval on 2022-07-21 at 14:23.","This Thesis was approved for publication on 2022-07-21 at 15:48.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18417 on 2022-11-15 at 18:22:03","The next generation of tokamaks (SPARC, ARC, FNSF, DEMO) and several current tokamaks (WEST, etc.) will operate with Ion Cyclotron Resonance Heating (ICRH) as their sole auxiliary heating technique because it transfers power directly to the ions, and it involves the cheapest radio frequency (RF) components. During ICRH operation, RF sheaths form on the ICRH antenna itself, as well as on far-field magnetically-connected surfaces. However, RF sheaths are associated with large hot-spot formation and large impurity emissions. This work presents high-resolution numerical experiments on RF sheaths in nuclear fusion scenarios using hPIC2, a GPU-accelerated hybrid fluid-kinetic particle-in-cell code. The combined data from these experiments was obtained using super computing GPU-accelerated hardware which would require hPIC2 over 10 years of run time, were it running in single-core CPU mode. The experiments reveal a new RF sheath phenomenon which occurs when the radio frequency is on-par with ion cyclotron frequency in an oblique magnetic field. Due to the $1/R$ scaling of the magnetic field in a Tokamak, such cases are possible on a surface on-axis near the bottom of the vacuum chamber, with the precise location, whether on the divertor or the vacuum chamber first wall, dependent on the geometry of the tokamak. The combination of RF and cyclotron frequency are analogous to the classical driven, damped harmonic oscillator, where charge density damps ion admittance. This study shows that the resulting resonance can lead to increased ion flux at the wall and material sputtering."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/116285"],"dc:language":["en","eng"],"dc:rights":["Copyright 2022 Mikhail Rezazadeh"],"dc:subject":["Radio frequency","radiofrequency","fusion","nuclear","admittance","resonance"],"dc:title":["RESONANCE in radio frequency sheath admittance in nuclear fusion scenarios"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Nuclear, Plasma, Radiolgc Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:56Z"}