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Non-Maxwellian Velocity Distributions on Tycho’s SNR J.C. Raymond, P.F. Winkler, W.P. Blair, J.J. Lee, S. Park
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Balmer lines Profiles H from H atoms excited before Charge Transfer form Narrow Component. H from atoms excited after Charge Transfer form Broad Component. H I e-e- proton h Ghavamian et al. 2002 Shock Narrow Component Unresolved Broad post-shock f(v) (weighted by CX Heng & McCray)
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Tycho’s SNR Shock HST; Lee et al. MMT slit positions Also HET spectra of 4 positions
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2 and 3 Gaussian fits to profile FWHM = 1540 km/s V = 120 km/s FWHM = 1160, 2230 km/s V = 115, 140 km/s
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Explanations: Superposition of different Proton Temperatures along LOS Fits give factor of 2 difference in FWHM, which implies factor of 4 in n 0 Implies rapid changes in morphology Charge Transfer velocity dependence Heng, van Adelsberg, McCray Cuts off wings rather than enhances, but sums different profiles. Looks like Gaussian for 2000 km/s Van Adelsberg et al.
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MORE Explanations Modified Shock Continuous range of T Blends Narrow & Broad components? Subshock jump could be 2X. Power Law Tail Vladimirov et al.
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Non-Maxwellian Proton Distributions Potentially Important for Injection as well as Diagnostics Neutrals ionized downstream are like Pickup Ions (Related to ACRs) VSVS V S /4 V PERP = ¾ V S Sin V PAR = ¾ V S Cos
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Bispherical Velocity DistributionThermal + Pickup Distribution Proton Velocity Distribution Formation of bispherical distribution transfers energy to waves; may heat protons or electrons. Raymond, Isenberg & Laming
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Better fit than two Gaussians Not as good as three, but fewer free parameters Parameter space not fully explored
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In Conclusive Good enough data reveal non-Gaussian profiles Superposition of different T must happen at some level Pickup Ion profiles must be present at some level Charge transfer distortion of profile probably not important in Tycho CR modified shock temperature profile might contribute Power law tail due to acceleration might contribute
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