New Year’s Comet
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Transcript of New Year’s Comet
New Year’s Comet
Evolution of Magnetic Fields in Convection Zone
• Study of the evolution of magnetic fields in the convection zone over cycle 23 from SOHO/MDI oscillation measurements
• Poloidal field + double-peaked near-surface toroidal field– Poloidal: 124 ± 16 G
– Toroidal: 380 ± 30 @ 0.999 R 1.4
± 0.2 kG @ 0.996 R
• Field strengths highly correlated with surface activity
Baldner et al.: 2009, ApJ 705, 1704
Quasi-periodic Oscillations in LASCO CME Speeds
• Analysis of the speed-distance profiles of a sample of 116 CMEs
• 15 cases show quasi-periodic oscillations with periods from 48 to 240 min
• Oscillations interpreted as normal modes of 3D flux ropes
Shanmugaraji et al.: 2010, ApJ 708, 450
The Nascent Fast Solar Wind Observed in the Corona by Hinode/EIS
• Origin of fast solar wind one of the most important unresolved problems in space and solar physics
• Deep exposures in corona hole with EIS reveals first spectroscopic signatures of nascent fast solar wind at coronal temperatures (T > 1 MK)
• Outflows become stronger with increasing temperature
• Isolated outflow patches in transition region merge in corona, in agreement with scenario of solar wind outflow being guided by expanding magnetic funnels
Tian et al.: 2010, ApJ 709, L88
Temperature / MK0.63 1 1.3 1.8
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