Show simple item record

dc.contributor.advisorChairperson, Graduate Committee: Jiong Qiu; Robert Leamon (co-chair)en
dc.contributor.authorLowder, Christopher Alanen
dc.contributor.otherJiong Qiu, Robert Leamon and Yang Liu were co-authors of the article, 'Coronal hole detection and open flux measurements' in the journal 'The astrophysical journal' which is contained within this thesis.en
dc.contributor.otherJiong Qiu and Robert Leamon were co-authors of the article, 'Coronal holes and open flux in solar cycles 23 and 24' submitted to the journal 'The astrophysical journal' which is contained within this thesis.en
dc.contributor.otherJiong Qiu, Robert Leamon and Dana Longcope were co-authors of the article, 'A flux transport model for computation of open magnetic field' submitted to the journal 'The astrophysical journal' which is contained within this thesis.en
dc.description.abstractCoronal holes are regions of the Sun's surface that map the footprints of open magnetic field lines as they extend into the corona and beyond, into the heliosphere. Mapping their footprint 'dance' throughout the solar cycle is crucial for understanding this open field contribution to space weather. Coronal holes provide just this proxy. Using a combination of SOHO:EIT, SDO:AIA, and STEREO:EUVI A/B extreme ultraviolet (EUV) observations from 1996-2014, coronal holes can be automatically detected and characterized throughout this span, enabling long-term solar-cycle-timescale study. I have developed a routine to enable automated computer recognition of coronal hole boundaries from these EUV data. The combination of SDO:AIA and STEREO:EUVI A/B data provides a new viewpoint on understanding coronal holes. As the two STEREO spacecraft drift ahead of and behind the Earth in their orbits, respectively, they are able to peek 'around the corner', providing the ability to image nearly the entire solar atmosphere in EUV wavelengths, using SDO data in conjunction. On the far-side of the Sun, evolving open magnetic field structures impact space weather, despite being unobservable until rotating into view by Earth. By combining our numerical models of solar magnetic field evolution with coronal hole observations, comparison of far-side dynamics becomes possible. Model constraints and boundary conditions are more easily fine-tuned with these global observations. Long-term and transient coronal holes both play an important role as observational signatures of open magnetic field. Understanding the dynamics of boundary changes and distribution throughout the solar cycle yields important insight into connecting models of open magnetic field.en
dc.publisherMontana State University - Bozeman, College of Letters & Scienceen
dc.subject.lcshSolar magnetic fieldsen
dc.subject.lcshCoronal holes (Astronomy)en
dc.subject.lcshSolar cycleen
dc.titleConnecting coronal holes and open magnetic flux through observation and models of solar cycles 23 and 24en
dc.rights.holderCopyright 2015 by Christopher Alan Lowderen
thesis.catalog.ckey2898825en, Graduate Committee: David McKenzie; Carla Riedel; Dana W. Longcopeen

Files in this item


This item appears in the following Collection(s)

Show simple item record

MSU uses DSpace software, copyright © 2002-2017  Duraspace. For library collections that are not accessible, we are committed to providing reasonable accommodations and timely access to users with disabilities. For assistance, please submit an accessibility request for library material.