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Space Weather Forecast With HMI Magnetograms: Proposed data products. Yang Liu, and HMI Team. Proposed data products with HMI magnetograms. Data products; Model products; Indices from data and modelings. Data products. Full disk magnetograms;
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Space Weather Forecast With HMI Magnetograms: Proposed data products Yang Liu, and HMI Team
Proposed data products with HMI magnetograms. • Data products; • Model products; • Indices from data and modelings.
Data products • Full disk magnetograms; • Line-of-sight magnetograms – cadence TBD (as high as 45 sec). • Vector magnetograms – cadence TBD (as high as 12 minutes). • Movie of line-of-sight magnetograms – 12 day history, update at TBD. • Active region patches; • Vector magnetograms on patches – cadence TBD. • Line-of-sight magnetograms on patches –cadence TBD. • Movie of line-of-sight for each patch – cadence TBD. • Synoptic maps. • Synchronic frame of radial field – update each 96 minutes (?). • …
Model products • Coronal field models – cadence TBD; • Global – PFSS, Hybrid, MHD. • Local – Potential field, NLFFF, MHD. • Field lines, source surface maps, MHD quantities, … • Magnetic field global harmonic coefficients; • Open field footpoints – coronal holes; • Horizontal flow from FLCT; • Velocity data from DAVE4VM/ILCT; • 1 AU predictions – solar wind speed, field polarity, field strength, …, from PFSS, MHD, … • …
Proposed parameters (likely related with the space weather forecast) • Solar active regions. • Basic parameters: unsigned flux, net flux, tilt, separation. • Solar flares. • Indices. • Flares or CMEs (failed or successful eruptions); • Decay index of magnetic field overlying magnetic neutral lines. • CMEs’ speed. • Reconnection flux and background field configuration. • Orientation of magnetic cloud. • Direction of heliospheric current sheet. • Interplanetary magnetic field. • Solar mean field and PFSS/MHD modeling. • Solar wind speed.
Basic parameters for active regions • Total unsigned flux: describe the size of an active region (Fisher et al. 1998), and related with potential field energy; • Net flux: might indicate how much the large scale flux involved in a region. CMEs are believed to be related with large scale fields.
Basic parameters for active regions (cont.) • Tilt angle: how far an active region away from normal, might indicate how complex the field configuration is. • Separation: indicate how compact an active region is. From Fisher (2000)
Basic parameters for active regions (cont.) • Tilt angle: how far an active region away from normal, might indicate how complex the field configuration is. Bipolar magnetic field regions (Tian et al. 2002) Flare-productive ARs (Tian et al. 2003)
Basic parameters for active regions (cont.) • Separation: indicate how compact an active region is. Wang & Sheeley (1989)
Indices for flare prediction • Hagyard (1987), Wang et al. (1994) (with vector magnetic field data): Magnetic shear along the neutral lines. • Falconer et al. (2002, 2005, 2006, …) (with vector field and line-of-sight field data): magnetic neutral line. • Leka et al. (2003a,b; 2007; …), Barnes et al. (2006; 2008; …) (vector magnetic field data): tens of indexes explored. • Schrijver (2005; 2007; …) (line-of-sight magnetograms): field structure away from potential field; unsigned flux along neutral line with strong field and high gradient. • Georgolis/LaBonte (2006; 2007; …) (vector magnetic field): helicity. • Welsch et al (2009) (line-of-sight magnetograms): with information of flows, evolution … • Many others, such as Jing et al. (2006); Cui et al. (2006; 2007); Guo et al (2006) … • Systematic study is needed for seeking for index or indices to be effectively used for forecast.
Flares or flares/CMEs: failed, ejective • Decay index n of overlying magnetic field (Simulation :see Torok & Kliem 2005; Fan & Gibson 2007). Courtesy: Kliem & Torok
Flares or flares/CMEs: failed, ejective • Decay index n of overlying magnetic field (Observation).
CMEs’ speed • Reconnection flux, and background field configuration. Qiu & Yurchyshyn (2005) Type 3 Type 2 Type 1
Orientation of magnetic cloud • Agreement between the directions of the heliospheric current sheet and the magnetic cloud (see, Zhao & Hoeksema 1998; Yurchyshyn 2008; Yurchyshyn & Tripathi 2009). Yurchyshyn 2008
Interplanetary magnetic field and solar mean field • Correlation between solar mean field and interplanetary magnetic field (see, e.g. Kotov et al. 2002). Courtesy: Xuepu Zhao.
Solar wind speed • Wang-Sheeley (or Wang-Sheeley-Arge) model; MHD simualtions. Courtesy: Xudong Sun
Proposed parameters (potential to be used for space weather forecast) • Solar active regions. • Basic parameters: unsigned flux, net flux, tilt, separation. • Solar flares. • Indices (TBD). • Flares or CMEs (failed or successful eruptions); • Decay index of magnetic field overlying magnetic neutral lines. • CMEs’ speed. • Reconnection flux and background field configuration. • Orientation of magnetic cloud. • Direction of heliospheric current sheet. • Interplanetary magnetic field. • Solar mean field and PFSS/MHD modeling. • Solar wind speed.