{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/24373"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/24373","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Fragmentation of magnetically-supported, weakly-ionized molecular clouds","abstract":"We follow the evolution and fragmentation of isolated, magnetically-supported, weakly- ionized, self-gravitating molecular clouds in three dimensions. Although the model clouds are supported by the magnetic field, high-density, magnetically-supercritical fragments form due to the drift between the ions and the neutrals, ambipolar diffusion. To follow the evolution of the model clouds, we extended the publicly-available Zeus-MP code to include the effects of nonideal magnetohydrodynamics and have modified several algo- rithms to improve accuracy and convergence. We present the results of a parameter study which varies the ionization fraction, mass-to-flux ratio, and velocity perturbation in the model clouds.","abstract_html":"We follow the evolution and fragmentation of isolated, magnetically-supported, weakly- ionized, self-gravitating molecular clouds in three dimensions. Although the model clouds are supported by the magnetic field, high-density, magnetically-supercritical fragments form due to the drift between the ions and the neutrals, ambipolar diffusion. To follow the evolution of the model clouds, we extended the publicly-available Zeus-MP code to include the effects of nonideal magnetohydrodynamics and have modified several algo- rithms to improve accuracy and convergence. We present the results of a parameter study which varies the ionization fraction, mass-to-flux ratio, and velocity perturbation in the model clouds.","abstract_has_math":false,"creators":["Christie, Duncan A."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Mouschovias, T. Ch.","Stack, John D.","Wandelt, Benjamin D.","Looney, Leslie W."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-25T14:40:21Z","date_published":"2011-05-25T14:40:21Z","updated_at":"2026-07-22T22:25:23Z","subjects":["molecular clouds","magnetic fields","ambipolar diffusion","star formation"],"languages":["en"],"rights":["Copyright 2011 Duncan A. 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We present the results of a parameter study which varies the ionization fraction, mass-to-flux ratio, and velocity perturbation in the model clouds.","Item withdrawn by Rebecca Bryant (rabryant@illinois.edu) on 2011-04-20T18:35:58Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Christie_Duncan.pdf: 3073231 bytes, checksum: b333d96051b8da6f50edacaede99613e (MD5)","Made available in DSpace on 2011-05-25T14:40:21Z (GMT). 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Ch.","Stack, John D.","Wandelt, Benjamin D.","Looney, Leslie W."],"dc:creator":["Christie, Duncan A."],"dc:date":["2011-05-25T14:40:21Z","2013-05-26T10:00:23Z","2011-05"],"dc:description":["We follow the evolution and fragmentation of isolated, magnetically-supported, weakly- ionized, self-gravitating molecular clouds in three dimensions. Although the model clouds are supported by the magnetic field, high-density, magnetically-supercritical fragments form due to the drift between the ions and the neutrals, ambipolar diffusion. To follow the evolution of the model clouds, we extended the publicly-available Zeus-MP code to include the effects of nonideal magnetohydrodynamics and have modified several algo- rithms to improve accuracy and convergence. 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