1. Review of Observations of Particles From Solar Flares and Their Clues to the Structure of the IMF Joe Mazur The Aerospace Corporation Glenn Mason Johns Hopkins/APL Joe Dwyer Florida Institute of Technology Joe Giacalone & Randy Jokipii University of Arizona Ed Stone California Institute of Technology

2. SHINE 2006 WG3 - Turbulence 2 Introduction Energetic ions from solar flares sometimes arrive at Earth with velocity dispersion that allows us to see individual particle injections from active regions at the sun. The particle events often have drop-outs in intensity across all energies that are an effect of the structure of the interplanetary magnetic field, and not of particle release at the flare source. This talk will briefly review the observations and their interpretation using a model magnetic field that was developed to interpret the transport of energetic particles above the ecliptic plane via meandering field lines.

3. SHINE 2006 WG3 - Turbulence 3 Velocity dispersion is common to many acceleration sites Field-aligned beams in aurora: propagation distance ~10 3 km Drift echoes from substorms: propagation distance ~10 5 km ~10 seconds GEODESIC rocket flight data courtesy of J. Clemmons CRRES/MICS data courtesy of J. Fennell

4. SHINE 2006 WG3 - Turbulence 4 Velocity dispersion in energetic particles from solar flares Propagation distance ~10 8 km Multiple particle injections from a solar active region Particle intensity often varies by >10x during an event Sometimes do not observe the entire injection Mason, Mazur, & Dwyer ApJ Letters 525, L133-L136,1999

5. SHINE 2006 WG3 - Turbulence 5 Solar flares & escaping ions M. Aschwanden, Space Sci. Rev. 101, 1-227, 2002 Events have been studied since the 1970’s Enhanced in 3 He (~1000x), Ne- Fe (~10x), trans-Fe (~1000x) compared to solar corona Sometimes fully stripped up to Si Beams of 10-100 keV electrons Gyroresonant wave-particle interaction in a 3-5 MK plasma may account for enrichments ( 3 He: Temerin & Roth 1992, Ne- Fe: Miller et al. 1993)

6. SHINE 2006 WG3 - Turbulence 6 Glimpses of small-scale (~1 hour) variations in solar energetic particles Anderson & Dougherty, Solar Phys. 103, 165-175, 1986.Buttighoffer, Astron. & Astrophysics 335, 295-302, 1998

7. SHINE 2006 WG3 - Turbulence 7 Glimpses of small-scale variations in solar energetic particles McCracken & Ness, JGR 71, pp. 3315-3318, 1966

8. SHINE 2006 WG3 - Turbulence 8 Ultra-Low Energy Isotope Spectrometer 0.02-10 MeV/nucleon Dual time-of-flight measurements for improved mass resolution  m /m ~ 0.03

9. SHINE 2006 WG3 - Turbulence 9 3 He Time Mass

10. SHINE 2006 WG3 - Turbulence 10 New views of the time- dependence of solar particle events Low-energy threshold so an event lasts many hours Large collecting area for low-intensity events that previous instruments would have missed A new look with ULEIS sensitivity

11. SHINE 2006 WG3 - Turbulence 11 Puzzling cases of “missing” ions Mason, Mazur, & Dwyer ApJ Letters 525, L133-L136,1999

12. SHINE 2006 WG3 - Turbulence 12 Time& spatial scales of events 25 events 11/97 to 7/99 Tallied duration of “sub- intervals” Factored in solar wind speed to convert to a spatial size Edges of drop-outs as sharp as ~2 minutes (~5x10 4 km or ~ few gyroradii of 1 MeV/n 56 Fe +18 ) Mazur et al. ApJ Letters 532, L79-L82, 2000

13. SHINE 2006 WG3 - Turbulence 13 CME-related events Events associated with large coronal mass ejections do not have drop-outs Reames et al., ApJ, 466, 1996

14. SHINE 2006 WG3 - Turbulence 14 Survey results Solar wind correlation length: Matthaeus, Goldstein, & King, JGR 91, 59-69, 1986

15. SHINE 2006 WG3 - Turbulence 15 Suprathermal electrons Gosling et al. ApJ 614, 412-419, 2004 Common features in ions and suprathermal electrons (<1.4 keV) (akin to electron obs. of Anderson & Dougherty 1986) Gosling et al. (2004) showed 2 events where the ions had dropouts but the electrons did not, possibly indicating a more uniform and/or broad electron source ions electrons

16. SHINE 2006 WG3 - Turbulence 16 Simultaneous observations of the same flare injection on 12 August 2000: ACE & Wind spacecraft The later arrival of empty flux tubes at Wind is consistent with solar wind convection UT Simultaneous Wind/ACE observations C-Fe

17. SHINE 2006 WG3 - Turbulence 17 Numerical simulations of particle transport Model field used to study propagation of particles from corotating interaction regions to high heliographic latitudes (Giacalone 1999) Model was based on earlier work by Jokipii & Parker (1968) and Jokipii & Kota (1989) Random motion of field line footpoints in the photosphere over ~4x10 4 km, time scales of ~1 day

18. SHINE 2006 WG3 - Turbulence 18 Giacalone, Jokipii, & Mazur, ApJ Lett. 532, 2000 The model followed the trajectories of 8 keV/n to 20 MeV/n oxygen from an impulsive flare The particles traveled through pre-existing IMF structures After ~1 day, ions were still present inside 1 AU and populated field lines spanning ~10º in longitude

19. SHINE 2006 WG3 - Turbulence 19 Simulated velocity dispersion & time- dependence with two different source sizes Same realization of the magnetic field Large sources (corresponding to a CME shock) generate continuous event profiles Giacalone, Jokipii, & Mazur, ApJ Lett. 532, 2000

20. SHINE 2006 WG3 - Turbulence 20 Closer look at dropout “edges”: iron

21. SHINE 2006 WG3 - Turbulence 21 Closer look at dropout “edges”: iron At 1700Z: B ~ 24 nT V sw ~ 580 km/sec

22. More examples, viewed with iron

23. Questions 1.What observables in the 1 AU solar particle data might be used to establish the source of these dispersionless features (i.e. turbulence or field-line mixing from footpoint motion at the sun)? 2.What inner heliosphere measurements of the IMF and of the energetic particles, on Sentinels for example, would clearly establish the origin of these features? 3.Are the Ulysses observations of Jovian electrons as far as ~2 AU from Jupiter (McKibben et al. 2006) a valuable constraint on either the turbulence or random walk model? 4.What other observables in these data would be of use? (solar cycle dependence; statistics of the scale of the ‘dropout’ edges)

24. SHINE 2006 WG3 - Turbulence 24 New Capability: Advanced Composition Explorer ACE launched in August 1997 The ACE objective is to collect samples of matter in the solar system using large instruments We do the collecting by letting the matter come to ACE and transmitting the results to Earth

25. SHINE 2006 WG3 - Turbulence 25 3 He-rich Solar Flares Discovered in late 1960s 3 He/ 4 He ratio in solar wind ~5x10 -4 The events drew attention because 3 He/ 4 He> 0.1 without any accompanying 2 H or other secondaries as one might expect from spallation in the solar atmosphere Later found enhancements of heavy ions up to iron by factor of 5-10 as well as: –Impulsive electron events –Scatter-free propagation –Often lack of any flare association on Sun –Sometimes ions fully stripped of electrons Mason et al. ApJ 574, 1039--1058, 2002 3 He 4 He

26. SHINE 2006 WG3 - Turbulence 26 ACE Survey of Flare Spectra Searched for periods with clear flare velocity dispersion –Deleted events with local acceleration –Required complete observation of event (i.e. that ACE remained connected to it) for whole energy range of instrument Cases often involved multiple injections; each event separated, and fluences calculated Mason, Dwyer, & Mazur ApJ Lett. 545, 2000