Stanford, January 27 2005

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 5000 = 1 must be like

Stanford, January 27 2005

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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, 2000Gallagher, P. personal communication 2004

Stanford, January 27 2005

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Archive cartoon fromGurman, 1987 - showsHE region nicely

0 -rays, magnetarrays, below = 1

Stanford, January 27 2005

Particle model uncertainties

• What is the source?

• Propagation at depth: B ~ P (not divergence-free!)

• Ad-hoc assumption about wave distribution (for pitch-angle scattering)

Stanford, January 27 2005

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MDI magnetic artifacts (D. Brown) showlocations 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 B2/8

Stanford, January 27 2005

Ramaty et al., ApJ 455, 193, 1995: protons can rivalelectrons for total energy

Stanford, January 27 2005

E E

Bremsstrahlung Nuclear excitation

Bad Bad

Stanford, January 27 2005

Flare/Magnetar comparison

• Flare impulse via particles above photosphere, ~1032 ergs, localized, extended in time

• Magnetar impulse via -rays below photosphere, ~1022 ergs, distributed across hemisphere, 0.2 s duration

Stanford, January 27 2005

QuickTime™ and aTIFF (Uncompressed) decompressor

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