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Solar Source and Magnetic Cloud Yang Liu – Stanford University yliu@solar.stanford.edu
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Erupted filaments in quiet Sun and magnetic cloud A relationship between erupted filament in the quiet sun and the magnetic cloud has been established. A relationship between erupted filament in the quiet sun and the magnetic cloud has been established. Pioneer work done by Marubashi (1986), followed by Bothmer & Schwenn (1994), Rust (1994), Bothmer & Rust (1997), Marubashi (1997), Zhao & Hoeksema (1998), McAllister & Martin (2000), and Ruzmaikin et al (2003). Pioneer work done by Marubashi (1986), followed by Bothmer & Schwenn (1994), Rust (1994), Bothmer & Rust (1997), Marubashi (1997), Zhao & Hoeksema (1998), McAllister & Martin (2000), and Ruzmaikin et al (2003).
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Active regions and magnetic clouds Active region as a whole body: no correlations have been found. Active region as a whole body: no correlations have been found. Pudovkin (1977): Pudovkin (1977): 22 cases; IMF orientation agrees with the orientation of the meridional component of the background field in the flaring regions (but used an average of the IMF for those events). 22 cases; IMF orientation agrees with the orientation of the meridional component of the background field in the flaring regions (but used an average of the IMF for those events). Tang et al (1985): Tang et al (1985): 12 cases; Shows no correlation between flare field orientation and IMF orientation. 12 cases; Shows no correlation between flare field orientation and IMF orientation. Montana State U. folks (Pevtsov & Canfield, 2001; Leamon et al 2002, 2004): Montana State U. folks (Pevtsov & Canfield, 2001; Leamon et al 2002, 2004): Pevtsov & Canfield (2001): magnetic structure of individual active region plays a role in geomagnetic events; Pevtsov & Canfield (2001): magnetic structure of individual active region plays a role in geomagnetic events; Leamon et al (2002): 46 events from sigmoidal active regions. Only 70% of them have the same handedness with magnetic clouds (For erupted filaments in quiet sun, 95% agreement was found); Leamon et al (2002): 46 events from sigmoidal active regions. Only 70% of them have the same handedness with magnetic clouds (For erupted filaments in quiet sun, 95% agreement was found); Leamon et al (2004): 12 events with vector magnetograms available. Fluxes of AR and MC are comparable; electric currents of them are different in orders; twists of them are different in one order (AR’s is one order smaller than MC’s); no correlations for handedness. Leamon et al (2004): 12 events with vector magnetograms available. Fluxes of AR and MC are comparable; electric currents of them are different in orders; twists of them are different in one order (AR’s is one order smaller than MC’s); no correlations for handedness.
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Active regions and magnetic cloud The erupted filaments in AR and magnetic clouds: limited case study cannot establish a correlation. The erupted filaments in AR and magnetic clouds: limited case study cannot establish a correlation. Webb et al (2000): Webb et al (2000): May 12 1997 event; May 12 1997 event; Filament defines orientation and handedness; Filament defines orientation and handedness; Dimming areas define footpoints of the modeled rope Dimming areas define footpoints of the modeled rope Agreement was found between the filament and MC in terms of orientation, handedness and flux. Agreement was found between the filament and MC in terms of orientation, handedness and flux. Yurchyshyn et al (2001): Yurchyshyn et al (2001): Two cases; Two cases; Filament defines orientation, LFFF defines handedness; Filament defines orientation, LFFF defines handedness; Agreement was found between the filaments and MCs. Agreement was found between the filaments and MCs.
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Active regions and magnetic cloud Post-flare arcades and magnetic clouds: a relationship has not yet been established. Post-flare arcades and magnetic clouds: a relationship has not yet been established. Yurchyshyn et al (2005): Yurchyshyn et al (2005): Two cases (Oct 28 2003 and Nov. 18, 2003); Two cases (Oct 28 2003 and Nov. 18, 2003); 50% agreement. 50% agreement.
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Active regions, CMEs and magnetic clouds A correlation has not yet been established. A correlation has not yet been established. Krall et al (2006): Krall et al (2006): Only one case (Oct. 28, 2003); Only one case (Oct. 28, 2003); Chen J. flux rope model (1996); Chen J. flux rope model (1996); LASCO images to define flux rope parameters; LASCO images to define flux rope parameters; NL orientation to define twist; AR size to define distance of footpoints of flux rope. NL orientation to define twist; AR size to define distance of footpoints of flux rope. Yurchyshyn et al (2006; 2007): Yurchyshyn et al (2006; 2007): LASCO images to define orientation of flux rope. LASCO images to define orientation of flux rope. Agreement between modeled flux rope orientation and magnetic cloud is at a level of 67% in a sample of 25 events. Agreement between modeled flux rope orientation and magnetic cloud is at a level of 67% in a sample of 25 events.
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Summary A good relationship has been established between the erupted filaments in the quiet sun and the magnetic clouds; A good relationship has been established between the erupted filaments in the quiet sun and the magnetic clouds; There is still a long way to go to recover a whole picture between the active regions, flares, CMEs and magnetic clouds. There is still a long way to go to recover a whole picture between the active regions, flares, CMEs and magnetic clouds.
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Questions to be addressed to establish a link Identifying actual erupted flux rope (or field) in active regions; Identifying actual erupted flux rope (or field) in active regions; Filament in AR? Post-flare arcades? Something else? Filament in AR? Post-flare arcades? Something else? Distortion & change of magnetic field structure of flux rope during eruption; Distortion & change of magnetic field structure of flux rope during eruption; For example kink instability (Fan & Gibson 2007). For example kink instability (Fan & Gibson 2007).Fan & Gibson 2007Fan & Gibson 2007 Coupling the local field and global field; Coupling the local field and global field; For example, EIT dimming (global and local; Zhukov et al 2007). For example, EIT dimming (global and local; Zhukov et al 2007). Interaction between the erupted rope and the heliospheric current sheets; Interaction between the erupted rope and the heliospheric current sheets; Pioneer work done by Zhao & Hoeksema (1996), followed by Yurchyshyn et al (2006). Pioneer work done by Zhao & Hoeksema (1996), followed by Yurchyshyn et al (2006). Distortion of configuration of flux rope due propagation in the interplanetary space: interaction with ambient solar wind. Distortion of configuration of flux rope due propagation in the interplanetary space: interaction with ambient solar wind. Only MHD experiments have been done (Gosling & Riley, 1996; Riley 1997; Odstrcil & Pizzo 1999; Schmidt & Cargill 2001; Riley & Crooker 2004). Only MHD experiments have been done (Gosling & Riley, 1996; Riley 1997; Odstrcil & Pizzo 1999; Schmidt & Cargill 2001; Riley & Crooker 2004).
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Dst Dependence on V and B Gonzalez et al., Yurchyshyn et al., Zhang et al……. CMEs measured days before MCs measured min before R2O From Gopalswamy 2007, LWS
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