1. Sinaia, September 6-10, 20051 Berndt Klecker Max-Planck-Institut für extraterrestrische Physik, 85741 Garching, Germany Workshop on Solar Terrestrial Interactions from Microscale to Global Models Sinaia, Romania, September 6 - 10, 2005 Heavy Ion Charge States in Solar Energetic Particle Events

2. Sinaia, September 6-10, 20052 Introduction Measurement Techniques Ionic Charge State (Fe, Ne, Mg, Si) in IP Shock /CME Related SEP Events Ionic Charge States (Fe, Ne, Mg, Si) in 3 He-rich and Heavy Ion-rich Events The Energy Dependence of Ionic Charge States - Mechanisms Summary OUTLINE

3. Sinaia, September 6-10, 20053 ENEGETIC PARTICLES IN THE HELIOSPHERE

4. Sinaia, September 6-10, 20054 Information on the Source i.e. Solar (Solar Wind, Corona); Interstellar, e.g. He + Pickup Ions For Solar Source: Source Location (Temperature, Density) Important Information on Fractionation, Acceleration and Propagation Processes Injection, Acceleration and Propagation generally depend on Rigidity, i.e. particle velocity v and M/Q INTRODUCTION Why are Ionic Charge States Important?

5. Sinaia, September 6-10, 20055 WHERE DO SOLAR ENERGETIC PARTICLES COME FROM ? The Historical Development Forbush, 1946 Phase 1: Everything comes from Flares Phase 2: ~ 70s to 90s Flares and CMEs / Shocks Impulsive and Gradual SEPs Phase 3: Present Flares and CMEs / Shocks Relative Contribution to SEPs under Debate Classification of 2 distinct types of SEPs events in question. Lin, 1970; Pallavicini et al., 1977, Reames 1999 1 st measurement of 2 GLEs in 1942

6. Sinaia, September 6-10, 20056 Average of 20 Events Energy: 385 keV/nuc IMPULSIVE EVENTS Average Elemental Abundances Mason et al., 2002, 2004 Reames, 1999 NEWNEW

7. Sinaia, September 6-10, 20057 Results from early measurements at ~1 Mev/nuc: Q m (Fe) ~12 -16 -> T e ~ 1.5-2 10 6 K Coronal Temperatures Q ~ Solar Wind, but somewhat larger (Fe) EARLY RESULTS for Large (gradual) IP-Shock Related SEP Events Gloeckler et. al., 1976, Hovestadt et al. 1981, Luhn et al., 1984

8. Sinaia, September 6-10, 20058 Q m (Fe) ~ 19-20, Q m (Si) ~14 -> T e ~10 7 K EARLY RESULTS for 3 He-, Fe-rich (Impulsive) SEP Events Klecker et al., 1984, Luhn et al., 1987

9. Sinaia, September 6-10, 20059 EARLY RESULTS Puzzle: Gradual: Q at ~1 MeV/n similar to Solar Wind, but for some ions (e.g. Fe) higher than in Solar Wind Impulsive: Si fully ionized, i.e. M/Q=2 How can abundances be enhanced relative to C or O (M/Q=2 for C - Si) Question:Measurement only in small energy range at ~1MeV/nuc. How is Q at other energies?

10. Sinaia, September 6-10, 200510 1)In-Situ Measurement (e.g. by Electrostatic Deflection) Energy range from Solar Wind energies to a few MeV/amu Advantage: Direct Measurement of E, M, Q, Q Distribution, Energy Dependence Q (E) 2) Measurement of the Rigidity Cutoff in the Earth’s Magnetic Field Measurement of M, E, R cutoff > Determination of average Q Advantage: Q Determination to High Energies of 10s of MeV/amu 3) Indirect Methods using information on Energy Spectra, Composition, or time- intensity profiles Disadvantage: Model dependent IONIC CHARGE DETERMINATION Measurement Techniques

11. Sinaia, September 6-10, 200511 We want: E, M, QMeasurement of E/Q (electrostatic defl.) E/M (e.g. time-of-flight) E(SSD) Solar Wind:SWICS / Ulysses, SWICS/ACE, CTOF/SOHO Suprathermal:STOF /SOHO, SEPICA/ACE ~ 0.2 - 0.6 Mev/nuc: SEPICA/ACE ~ 0.5 - 2.0 Mev/nuc:IMP-7/8, ISEE-1/3 IONIC CHARGE DETERMINATION (1) In-Situ Measurements

12. Sinaia, September 6-10, 200512 1) In-Situ Measurement (e.g. by Electrostatic Deflection) Energy range from Solar Wind energies to a few MeV/amu Advantage: Direct Measurement of E, M, Q, Q Distribution, Energy Dependence Q (E) 2) Measurement of the Rigidity Cutoff in the Earth’s Magnetic Field Measurement of M, E, R cutoff > Determination of average Q Advantage: Q Determination to High Energies of 10s of MeV/amu 3)Indirect Methods using information e.g. on Energy Spectra, Composition, or time- intensity profiles Disadvantage: Model dependent IONIC CHARGE DETERMINATION Measurement Techniques

13. Sinaia, September 6-10, 200513 IONIC CHARGE DETERMINATION (2) Rigidity Cutoff of the Earth’s Magnetic Field Mason et al., 1995; Mazur et al., 1995; Leske et al., 1995; Oetliker et al., 1997 Determine c (R c ) with ions of known charge (H + ) on an orbit-by orbit bases Determine c for other ions Compute Q avg from R c, c and E, M Advantage: Large Energy Range Energy Dependence Disadvantage: Intensity needs to be large SAMPEX ( polar Orbit, ~ 600 km altitude )

14. Sinaia, September 6-10, 200514 IONIC CHARGE DETERMINATION (2) Rigidity Cutoff Variations During SEP Events Leske et al., 2001 c (R c ) can vary by several degrees during an event Determine c for H + or He 2+ on an orbit by orbit basis Compute adjusted c from time variation Use c (R c ) or linear fit: cos 4 ( c ) = a R c +b to derive Q avg from R c, c and v, M Q avg = (M v) / (R c e) SAMPEX

15. Sinaia, September 6-10, 200515 3)Indirect Methods using information e.g. on Energy Spectra, Composition, or time - intensity profiles Disadvantage: Model dependent Energy Spectra: M/Q dependent roll-over of spectra (Tylka et al., 2000) Composition: M/Q-dependent fractionation effects (Cohen et al., 1999) Rigidity dependent interplanetary propagation: Time to maximum intensity ( O’Gallagher et al, 1976, Dietrich & Tylka, 2003) SEP decay phase (Sollitt et al., 2003) IONIC CHARGE DETERMINATION Measurement Techniques

16. Sinaia, September 6-10, 200516 IONIC CHARGE DETERMINATION (3) Indirect Methods 1. Fe X (E) ~ E  exp(-E/E 0X ) 2. E 0X =E 0H *(Q/M)   April 20-24, 1998 Tylka et al., 2000 Determine E 0X,   from spectral fit Determine M/Q from (2)

17. 17 IONIC CHARGE DETERMINATION Experiments and Energy Range EEARLY MEASUREMENTS FROM IMP-7 / 8, ISEE - 1/3 RECENT MEASUREMENTS FROM SAMPEX - SOHO - ACE

18. Sinaia, September 6-10, 200518 NEW RESULTS (SAMPEX-SOHO-ACE) Gradual Events: Mean Ionic Charge Varies With Energy SAMPEX: Mason et al., 1995; Leske et al., 1995, Oetliker et al., 1997) Systematic Increase of Q with Energy above ~10 MeV/amu, in particular for Fe Oct. 1992

19. Sinaia, September 6-10, 200519 NEW RESULTS (SAMPEX-SOHO-ACE) Gradual Events: Large Variability of Q (E) Möbius et al., 1999, 2000, 2003; Bogdanov et al., 2000, Klecker et al. 2000, 2001, 2003; Popecki et al., 2000, 2001, 2003; Bamert et al., 2002; Labrador et al., 2003 Large Variability of Q (E) for Heavy Ions, in particular for Fe At energies above ~200 keV/nuc: Large Variability Q Fe (E) increasing at E > 10 Mev/nuc - often Q Fe (E) increasing at ~ 1 MeV/nuc - some cases At low energies of up to ~ 250 keV/amu: Q similar to Solar Wind Day 121, 1998 CME / IP Shock Event 0.01 - 0.1 MeV/n SW: 10.1

20. Sinaia, September 6-10, 200520 NEW RESULTS (SAMPEX-SOHO-ACE) Gradual Events: Mean Ionic Charge Varies With Energy SAMPEX Results Mason et al., 1995; Leske et al. 1995; Oetliker et. 1997; Mazur et al., 1999; Leske et al., 2001; Labrador et al., 2003 ACE Results Möbius et al., 1999, 2000, 2003; Bogdanov et al., 2000, Klecker et al. 2000, 2001, 2003; Popecki et al., 2000, 2001, 2003

21. Sinaia, September 6-10, 200521 NEW RESULTS (ACE+SOHO) Impulsive Events: Mean Ionic Charge Increases ALWAYS with Energy YEARDATEQ m (Fe) 0.18-0.43 QQ 1998252 00:29- 253 23:45 17.50.60 1999184 21:36- 186 06:00 14.90.60 1999201 02:19- 202 22:19 16.50.60 2000122 04:05- 122 23:54 15.20.55 Möbius et al., 2003; Klecker et al, 2005

22. Sinaia, September 6-10, 200522 IMPULSIVE EVENTS Ionic Charge of Ne, Mg, Si, Fe (ACE)

23. Sinaia, September 6-10, 200523 THE ENERGY DEPENDENCE OF THE IONIC CHARGE Overview of Possible Mechanisms 1)Ionization by e, p in a dense plasma in the low corona “Stripping Model” 2)Effect of Energy Spectra with M/Q-dependent roll-over (i.e. Acceleration and Propagation effects) 2)Mixing of 2 Sources: Solar Wind Origin and Flare Origin (i.e Heavy Ion Rich)

24. Sinaia, September 6-10, 200524 Comparison of Ionic Charge States with Stripping Model I. The Equilibrium Case The Equilibrium Case Impact ionization by p + e Radiative + dielectronic recombination 1.Q m at E < 0.1 MeV/amu depends on T e (electron distribution function) 2)Large Increase of Q m at E > 0.1 MeV/n by (p+e) impact ionization Electrons: Maxwell distribution Cross sections and rate coefficients: Arnaud & Raymond, 1992, Mazzotta et al., 1998; Kovaltsov et al. 2001 Ostryakov et al., 1999; Barghouty & Mewaldt, 1999; Kocharov et al., 2000 Klecker et al., 2005

25. Sinaia, September 6-10, 200525 Comparison of Ionic Charge States with Stripping Model II. The Non-Equilibrium Case The Non-Equilibrium Case Impact ionization by p + e Radiative + dielectronic recombination 1)Q m depends on N*t 2)Equilibrium will be reached for N * t ~ 1-10 * 10 10 cm -3 s (for E ~ 0.1 - 10 MeV/n) 3) Equilibrium N*t is energy dependent Kocharov et al., 2000 Q 24 20 16 12 8

26. Sinaia, September 6-10, 200526 Comparison of Fe Ionic Charge State Data with Stripping Model The Equilibrium Case 1.Q m at E < 0.1 MeV/n consistent with T e 1.2 - 1.4 10 6 K 2)Large Increase of Q m at E > 0.1 MeV/n N * t ~ 1 * 10 10 cm -3 s t ~ 1 - 100 s: N ~ 10 8 - 10 10 cm -3 -> Acceleration low in Corona 3) Increase of Q m with E larger than in equilibrium stripping model What is missing? Klecker et al., 2005

27. Sinaia, September 6-10, 200527 INTERPLANETARY TRANSPORT INCLUDING THE EFFECTS OF Model, including acceleration Kartavykh et al., 2005 DIFFUSIONCONVECTION ADIABATIC DECELERATION SOURCE Energy Loss by Adiabatic Deceleration 1/E dE/dt = 4/3 V sw / r s -1 Integrated (0.01 AU -> 1AU) energy loss depends on scattering mean free path and particle velocity.

28. Sinaia, September 6-10, 200528 A MODEL FOR ACCELERATION AND TRANSPORT Acceleration Model, including At the Sun: Spatial and Momentum Diffusion, Ionization, Coulomb Losses Interplanetary Space: Transport, including Spatial Diffusion, Convection, Adiabatic Deceleration. Simultaneous fit of: Energy Spectra Intensity-time profile Q Fe (E) (Kartavykh et al., 2004, 2005)

29. Sinaia, September 6-10, 200529 MODEL FITS FOR Ne, Mg, Si and Fe July 3, 1999 Event July 20, 1999 Event

30. Sinaia, September 6-10, 200530 THE ENERGY DEPENDENCE OF THE IONIC CHARGE 2. Effect of Energy Spectra with M/Q-dependent Roll-Over Klecker et al, 2001 Fe Mean Ionic Charge computed with sample SW-Fe ionic charge distribution

31. Sinaia, September 6-10, 200531 Mixing SW with Q Fe > 16 + from Impulsive Events Tylka et al. 2001 THE ENERGY DEPENDENCE OF THE IONIC CHARGE 3. Mixing of 2 Populations

32. Sinaia, September 6-10, 200532 SUMMARY-1 Impulsive Events All non Interplanetary Shock related 3 He-rich, Fe-rich events investigated so far show Q m (Fe) ~11 - 13 at 10 - 100 keV/n with a steep increase of Q m (Fe) to Q m (Fe) ~14 - 20 in the energy range 180 - 550 keV/n. For several events, the increase above ~200 keV/n is steeper than expected for charge stripping equilibrium conditions. Interplanetary transport effects (adiabatic deceleration) are important and can explain the steeper increase. Homogeneous models provide good fits, if Q(E) is not too steep Inhomogeneous models are required to explain observations of steeper charge spectra

33. Sinaia, September 6-10, 200533 SUMMARY-2 The steep increase of Q with E for E < 1 MeV/nuc requires acceleration low in the corona N *  A ~ 1-10 * 10 10 cm -3 s For  A ~ 10-100 s this corresponds to N ~ 10 8 -10 10 cm -3, i.e. altitudes < 2 R s High Charge States (e.g. Fe +20 ) observed at energies of ~ 1 MeV/n can be used as Tracer for a Source Low in the Corona

34. Sinaia, September 6-10, 200534 SUMMARY-3 Gradual Events High Charge States (and abundance enhancements) of Fe at Energies of ~ 1 MeV/nuc Acceleration low in the corona High Charge States (and abundance enhancements) of Fe at Energies > 10 MeV/nuc Option 1: Injection and acceleration in the contemporary flare Option 2: Injection and acceleration of 2 components by CME driven coronal shock (1) ~ solar composition, SW charge states (2) ‘flare’ composition (heavy ion rich, high charge states)