An Overall Framework for Solar Flares? H. S. Hudson Space Sciences Laboratory University of California, Berkeley CS-16 29/08/10

Dimming, implosion, oscillations

A broad framework How does the flare instability work? Formation of signatures Plasma physics Consequences - Coronal structure - Astrobiology? CS-16 29/08/10 What is the basic physics of a flare/CME, and how do we relate observations of many diverse types to understanding it? One natural approach is to make a cartoon, understood to be a kind of giant interpolation formula

CS-16 29/08/10 Contribution s welcome!

CS-16 29/08/10 Google “Flare Cartoons”

Cartoons CS-16 29/08/10 Tan & Huang 2006 Anzer & Pneuman 1982 Fletcher & Hudson Ergun et al. 2002

Formation of signatures: spectroscopy CS-16 29/08/10 Problem of solar UV spectroscopy (lack of!) The impulsive phase: transition between thermal and nonthermal plasma states Particle acceleration

Plasma physics I: particle acceleration CS-16 29/08/10 The impulsive phase: electrons at 10 4 kT dominate The coronal phase: L CR ~ 0.1 L bol Mewaldt et al. 2007

Plasma physics II CS-16 29/08/10 How does the flare instability proceed? How do we understand the coupling of scales? Physics of waves Ion-neutral physics in the chromosphere

Consequences CS-16 29/08/10 The nanoflare hypothesis Luminosity: Is the diverted energy important? Hard radiation and astrobiology?

A broad framework How does the flare instability work? Formation of signatures Plasma physics Consequences - Coronal structure - Astrobiology? CS-16 29/08/10 What is the basic physics of a flare/CME, and how do we relate observations of many diverse types to understanding it? One natural approach is to make a cartoon, understood to be a kind of giant interpolation formula

Conclusions Solar flares, for all their complexity, have simple organizing principles The basic question – “How does the impulsive phase work?” – remains unanswered CS-16 29/08/10 See also Hudson & Micela, CS-14

Thanks CS-16 29/08/10

Magnetic changes during flares “Confusogram” legend: 10x10 2.5” pixels 240 minutes time base 500 G magnetic range (Sudol & Harvey 2005)

CS-16 29/08/10 Flare energy Woods et al 2004 Hudson et al 2006 In time In space