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Solar flares, magnetars, and helioseismology. H.S. Hudson SSL/UCB. Outline. Working concept for flare physics Missing knowledge in the deep atmosphere Nature of impulse Magnetar behavior. Overlapping needs…. HE astrophysicists tell helioseismologists where the flare impulse happens
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Solar flares, magnetars, and helioseismology H.S. Hudson SSL/UCB Stanford, January 27 2005
Outline • Working concept for flare physics • Missing knowledge in the deep atmosphere • Nature of impulse • Magnetar behavior Stanford, January 27 2005
Overlapping needs… • HE astrophysicists tell helioseismologists where the flare impulse happens • Helioseismologists tell HE astrophysicists what sunspot magnetic fields above and below t5000 = 1 must be like Stanford, January 27 2005
Schrijver et al., Solar Phys. 206, 69, 2002 Stanford, January 27 2005
Four things the TRACE movie showed • Early inward motions, prior to the eruption • Dimming - the CME starting off • Excitation of coupled normal modes in the arcade • Arcade blowout • But mainly, that the energy release is COMPACT and BRIEF Stanford, January 27 2005
Forbes, T., JGR 105, 23,153, 2000 Gallagher, P. personal communication 2004 Stanford, January 27 2005
Archive cartoon from Gurman, 1987 - shows HE region nicely P0g-rays, magnetar g-rays, below t = 1 Stanford, January 27 2005
Particle model uncertainties • What is the source? • Propagation at depth: B ~ Pd(not divergence-free!) • Ad-hoc assumption about wave distribution (for pitch-angle scattering) Stanford, January 27 2005
MDI magnetic artifacts (D. Brown) show locations of particle precipitation in October 28, 2003 flare? Stanford, January 27 2005
Energy and momentum • Cross-sections and difficulty of inference • Total energies in particles • Recall Lin & Hudson 1976 (or Kane & Donnelly 1971): energetic electrons may contain the total flare energy after B2/8p Stanford, January 27 2005
Ramaty et al., ApJ 455, 193, 1995: protons can rival electrons for total energy Stanford, January 27 2005
Bremsstrahlung Nuclear excitation s Bad Bad E E Stanford, January 27 2005
Flare/Magnetar comparison • Flare impulse via particles above photosphere, ~1032 ergs, localized, extended in time • Magnetar impulse via g-rays below photosphere, ~1022 ergs, distributed across hemisphere, 0.2 s duration Stanford, January 27 2005