The Analysis of Solar Energetic Particles

WP13000: Solar Particle Emission AnalysisLeader: M. StoriniCo-leader: S. Gabriel(Drops of knowledge)( WG1/WP13000: Progress Report N° N 1 )WP13000The Analysis of Solar Energetic ParticlesMarisa Storini – IFSI/INAF Athens - 12 October 2005

The WG1/WP13000 (Solar Particle Emission Analysis inside the COST724 Action) officially started its work on October 10, 2004. Even ifrequired, the organization of a WG1 Science Meeting to addressWP13000 members to the relevant involved topics was not stillperformed (budgetary reasons). Nevertheless, a Global Archive forWP13000 containing useful references, available models and datasetswas initiated. Progress on such Archive is discussed together withsome preliminary results obtained by the EoC teams.Marisa Storini – IFSI/INAF Athens - 12 October 2005

The Analysis of Solar Energetic Particles (SEPs)CONTENTS• BRIEF OVERVIEW OF THE TOPIC• SEP FORECAST AND NOWCAST REQUIREMENTS• SEP ACCELERATOR MECHANISMS• SEP CODES• WG1/WP13000: Progress Report N° 1Marisa Storini – IFSI/INAF Athens - 12 October 2005

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsBRIEF OVERVIEW OF THE TOPIC - ISEPs are low-energy (about 10 7 –10 10 eV) cosmic rays seen as adistinct population in the interplanetary medium.PARTICLE ACCELERATORS FOR SEPsFilament eruptions ?Huge X-ray Arcades ?[ Reames, 1999 ]1 2(see Aran et al. [2004], Gabriel andPatrick [2003], Anastasiadis [2002],Ruffolo [ 2002], for details)SPE TIME PROFILE DURATION1: short (hours)2 : extended (days)

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsBRIEF OVERVIEW OF THE TOPIC - IIIMPULSIVE EVENTS• X-ray emission :Impulsive• Electron-rich events• 3He-rich events• Fe/O ~ 1• H/He ~ 10• Q Fe = 20• Preferred solar longitude> 20° W• Radio emision type : III,V(II)• High number of events/yrGRADUAL EVENTS• X-ray emission :Gradual• Proton-rich events• 3He/ 4 He ~ 0.0005• Fe/O ~ 0.1• H/He ~ 100• Q Fe = 14• No preferred solarlongitudes• Radio emission type: II,IV• Low number of events/yr

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsBRIEF OVERVIEW OF THE TOPIC - IIIKocharov and Torsti,2002A MORE COMPLEX SCENARIO(see e.g. ACE/SOHO News)

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsSEP FORECAST AND NOWCAST REQUIREMENTS - ISOLAR ATMOSPHERE‣when, where and how a solar flare (SF) occurTo know‣SF characteristics from the e.m. radiation and heliomagnetic field‣SF efficiency in SEP generation‣When, where a how a CME occur‣CME characteristics as discriminators between CME/SPE eventsand CME/no-SPE events‣CME/Shock association + shock efficiency in SEP accelerationSEP INJECTION IN THE INTERPLANETARY MEDIUM

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsSEP FORECAST AND NOWCAST REQUIREMENTS - IIINTERPLANETARY MEDIUM‣I-CME/Shock space-time evolution‣Shock efficiency for further SEP acceleration‣SEP transport in the interplanetary spaceTo know(including interplanetary shock acceleration, Alfvén wavegeneration and wave-particle interaction in shock’s vicinity,diffusion, adiabatic focusing, convection, adiabatic deceleration)‣SEP energy distribution‣Ion Abundances in SEPs‣SEP flux anisotropiesSEP EVENT RECORDED IN THE INTERPLANETARY MEDIUM

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsSEP ACCELERATOR MECHANISMSStochastic accelerationDC electric fieldsShock accelerationSpecial attention should be paid to the wave-particle acceleration(e.g.Bazilevskaya, , Energy spectrum of solar cosmic rays,SEE-2005- enclosed)

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsKING MODEL [1974]SOLPRO [1975]JPL-91 MODEL [1993]NYMMIK MODEL [1998]SEP CODESESP (Emission of Solar Protons) MODEL [1999, 2000]CREME MODEL [1996 and developments]UPDATED JPL PROTON FLUENCE MODEL [2002]SOLPENCO (SOLar Particle ENgineering Code) [2004 – ESA P.P.]NEURAL NETWORK PREDICTION TECHNIQUES [2003 anddevelopmentsand more …]

Marisa Storini – IFSI/INAF Athens - 12 October 2005The Analysis of Solar Energetic Particles (SEPsWe are preparingWG1/WP1300 – Progress Report N° N 1SEPs)M. StoriniL. BarbaneraM. LaurenzaData Resources(DR)The Global ArchiveReference Catalogue(Ref)URL : Internet ResourcesDR-B : Data BooksDR-A: Data ArticlesModels & Codes(M & C)• Collected~250 References)

Marisa Storini – IFSI/INAF Athens - 12 October 2005SEPs)The Analysis of Solar Energetic Particles (SEPsWG1/WP1300 – Progress Report N° N 1E.o.C. Teams• José Medina, Miguel A. Hidalgo and César Martín: The effect ofthe magnetic clouds over the solar energetic particle flux:preliminary results.• Catia Grimani for the PHOEBUS group: PHOEBUS UPDATE.• Monica Laurenza, Marisa Storini: QBO Role in Solar EnergeticParticle Emission, Trieste Meeting, 18-20 October 2005.• Mario Damasso, Marco Galliani, Mario Parisi, and Marisa Storini:More on Solar Energetic Particle Events, Trieste Meeting, 18-20October 2005.+2 posters for the SWW2 – November 2005.

Energy spectrum of solarcosmic rays *G.A. BazilevskayaLebedev Physical Institute, Russian Academyof SciencesSEE-2005International SymposiumNor Amberd, , Armenia26-30 September 2005* Partly performed for WG1/WP1300 of COST 724 Action

MotivationEnergy spectrum is one of most important features of solarenergetic particles. It is connected to acceleration,propagation, and loss mechanisms, as well as time andsite of particle generation and propagation.On the other hand, energy spectrum is a measurablefeature, however loaded with many signatures of abovementioned processes.It is hardly possible to disentangle and identify all factors ofthe spectrum formation from the observational data.The purpose of this talk is to outline the processes involvedin the spectrum formation and the state-ofof-art ofexperimental results.Large events are chosen for consideration.

Is it possible to make anyconclusion about particleacceleration on the Sunfrom the observed energyspectrum view?

Energy spectrum of solarcosmic rays in the large eventsContent‣ Processes affecting the observed spectra ofsolar energetic particles (SEPs(SEPs)‣ Signatures of the CME-driven shockprocesses‣ Acceleration in the DC electric fields‣ Stochastic acceleration‣ Observational data on the event of 20 January2005‣ Conclusion

Energy spectrum in the maximum of theIntensity-Time profileThe Bastille Day event1.E+06July, 2000J(>E),cm -2 s -1 sr -11.E+061.E+041.E+021.E+001.E-02GOESmax2max1>10 MeV>30 MeV>50 MeV>60 MeV>100 MeVNM Oulu12 14 16 18 20 22July, 2000J(>E),cm -2 s -1 sr -11.E+041.E+021.E+001.E-02GO,m1GO,m2NM,m1NM,m2Bal,m1Bal,m21 10 100 1000Е, MeVThe “spectrum in maximum” is conventionalcharacteristic of a SEP event

Processes being reflected on theobserved SEP fluxes‣ Acceleration on the Sun (in the flare and/or in thecorona)‣ Propagation in the corona and injection of particlesonto IMF line connecting the Sun and an observer‣ Propagation through interplanetary space includinginterplanetary shock acceleration, Alfvén wavegeneration and wave-particle interaction in shock’svicinity, diffusion, adiabatic focusing, convection,adiabatic deceleration

Acceleration mechanisms‣ Shock acceleration‣ Stochastic acceleration‣ The DC electric fields

Shock accelerationLaminar shock waveShock with theturbulent perturbationsE=-[uB]/c1 – upstream region, 2 – downstream region;u is bulk plasma flow velocity; σ = u 1 /u 2 is thecompression ratio; spectral indexγ = (σ+2)/(σ-1)

dJ22−(σ+2) /(σ−1)∝(E+2Em 0c)dEShock accelerationDiffusive shock acceleration (first-order Fermi acceleration): chargedparticles stream into magnetic perturbationsin the post-shock shock region, reflect, and arescattered back across the shock by the pre-shock Alfvén waves./v, where E and v are energy andvelocity of the particle and v c is velocity ofmagnetic compression.dE/dt ∝ v c /vSpectralform:dJdE∝( E2+2Em c02)−(σ + 2) /( σ −1)

Particle acceleration by CME-drivenShock waves. The observationalconsequences of proton-generatedwaves at shocks‣ The streaming limit‣ The spectral knee‣ Abundance variations

Panel (a) shows superposed intensity-time profiles of 3-6 MeV protons in severalevents with streaming limited intensities early in the events. Panel (b) shows similarlimits as a function of energy in the large 1989 October 19 event. Intensities often peakat the time of shock passage at values that are 10-100 times the streaming limit.D. V. Reames, 2000. The streaming limitEscape of particlesfrom the near-shock region isimpeded due tovery highintensities ofproton-generatedwaves. Someparticles aretrapped near theshock (ESPevents).

D. V. Reames, 1998 . The streaming limitIntensity-time profles of protons in three energy channels are shown for six large SEP eventsduring the last solar cycle as measured on the GOES spacecraft. Streaming-limited intensityvalues for each energy channel are shown as dashed lines.

Proton intensity is shown at the shock anda flattened spectrum is seen a fixeddistance away, according to Lee (1983)theory. Increasing the sourcedoes not increase the intensity observedat low energy.Calculations of the streaminglimited intensity of 1-MeV 1protons at 1 AU for shock at0,1 AU(NG and Reames, , 1994)

The spectral kneeEllison andRamaty, , 1985:spectrum turnover may resultsfrom adiabaticdeceleration inthe expandingblast wave, shocklifetimescomparable toparticleacceleration time,shock sizecomparable toparticle diffusionlengthLeft: A spectrum from spacecraft and the neutron monitor network in the 29September 1989 event with Eo = 1 GeV. Right: spectra from the 20 April 1998event with Eo = 15 MeV. (Reames, 2000). Proton intensities below ~50 MeV aresimilar in the both events.

Left: Wind/EPACT hourly averaged abundance ratios normalized toreference coronal values, during 20.04.1998 event [Reames[Reames, , 1995].Right: Simulation of these abundances [Ng et al., 1999]D. V. Reames, 2000.

Resume‣ Energy spectra are strongly affected byparticle-wave interaction leading to Alfvénwave amplification and fluxes distortion.‣ The “time-of-maximum” spectrum in thelarge SEP events seems not to reflectacceleration on the Sun.‣ The first to arrive most energetic particlescan give an insight in the solar processes.

Taken fromJ.-I. Sakai andC. de Jager,1996Stochastic acceleration – diffusion in themomentum space. dE/dt ∝ (v c /v) 2 , where E and vare energy and velocity of the particle and v c isvelocity of magnetic compression.Model of the flare(Aschwandenet al.,1995): reconnection inthe X-point X point is followedby a downwarddirected shocks andMHD turbulence.(Selective He 3acceleration may occuhere) . Timing is sec –min, , E is up to GeV,spectrum is a powerlaw (Bessel function folower energy).

1с1сε = - [V in B]E= e ε LacL ≈ 10 9 cm,V in ≈ 10 5 –10 6 cm/s,B ≈ 100–300 GLac

Particle acceleration in the DC electric fieldsReferenceLitvinenko,2003,reconnectionVashenyuk etal., 2003,reconnectionZharkova,Gordovsky,2005, recon.Browning,Vekstein, , 2001,reconnectionVeselovsky,2002, inductiveel. field inelectrojetsElectr.field,ε,V/cmLength, cmmax/prob.Energy, eVmax/prob.10 10≤1010 9 103x10 84x102 1010 /10 10 10 12Time ofacceler., sSpectral formE -γγ=2-312

Relativistic Particles are the best candidates toenable the observer to look at the accelerationprocessesRelativistic Particles are the first to be observed, so the time elapsed from theacceleration is minimalFast arriving is usually observed indicative of scatter-free propagation (minimaleffect of self-generatedAlfvén waves)Larmor radii of RelativisticParticles are

Fast–drift bursts (type III) can be used to trace field lines from theSun into the interplanetary medium. Emission above 100 MHzoriginates within 0.5 solar radii of the photosphere whereasemission at 10 MHz originates at about 2 solar radii. If the burstsextend to the lowest frequencies seen near Earth (typically ~30kHz) then there must be direct field line connection from theacceleration region to Earth (Cane et al., 2002)

GLE 20 January 2005Count rate enhancement, %Count rate enhancement, %GLE 20 January 2005 Neutron Monitor response6000500040003000200010000-10006 6.5 7 7.5 8 8.5 920 Jan. 2005, UTRc

GLE 20 January 2005Contribution at SEE-2005 meeting:‣ Nicolai Bostandjyan‣ Hamlet Martirosyan‣ Mary Zazyan

GLE 20 January 2005Count rate enhancement, %160140120100806040200-20GLE January 2005 Neutron Monitor Response6 6.5 7 7.5 8 8.5 920 Jan. 2005 UT2

Vashenyuk et al. 200520 January, 2005

‣The response of a neutron monitor to anisotropic flux of solarprotons (Shea(& Smart, 1982):20 GV(∆N N / N) j = ΣRc(dN/N)JJ ⎜⎜⎜⎜ (R) S(R) F ( (θ j (R)) A(R) d Rwhereis an effect at a given neutron monitor jJ || (R)is rigidity spectrum of SEP flux in the direction ofanisotropy axisS(R) is specific yield function (Debrunner(et al., 1984),F ( (θ j (R)) is pitch-angle distribution of SEPsθ j is pitch angle (angle between the anisotropy axis givenby Φ; Λ and asymptotic direction of a given neutron monitorat a given rigidity R)= 1 for allowed and 0 for forbidden trajectoriesA(R) = 1

Direction to the sourceof solar proton fluxes. 20 Jan. 2005Time07000800Sourcecoordinates26°S,-118°(242°E)35°S, 9° 9 GSE0650-06550655 60±3°S, 69±7°GEO0653-06550655-065740°S, 310°E50°S, 320°EGEO40°S, 40°WGEOCommentsAng.distr.σ≈0.3Fig.:~45°S,140°(confusedscale?) σ≈0.2ReferenceVashenyuket al. 2005Belov et al.2005Flückigeretal.2005Moraal etal.2005

J(>E), cm -2 s -1 sr -11.E+031.E+011.E-011.E-03Integral energy spectrum of protons20 Jan. 2005Belov0650-0655Belov0655-0700Vashenyuk07Vashenyuk08bal0732-0759G10max07101.E-051.E-03 1.E-02 1.E-01 1.E+00 1.E+01G11max0710G10 0700E, GeV

1.E+14Dif. spectra of protons20 Jan. 20051.E+11G11 max 0705-0710m -2 s -1 sr -1 GeV -11.E+081.E+051.E+021.E-01~E -1.25 ~E -4.78 exp(-E/0.72)ACE0900UTNM 0700UT Vashenyuk et al.w ithout carpet1.E-041E-04 0.001 0.01 0.1 1 10 100w ith carpet 0715UT Karpov et al.E, GeVWith account of CARPET the proton spectrumis reasonably approximated by a brokenpower law form

Energy spectrum of solarprotons, 20 Jan., 2005 (GLE data)Time070008000650-06550655Later0653-065506550655-065906590650-06550655after 0730Form1.5×1010 5 exp(-E/0.95 GeV)8×104 E - 4.6~E – 0.7~E – 4~E~E -3.7(~R-4.5)~E -5.8(~R- 7 )~E -2.9(~R~R -(2 (2.5-5.7)~E -4.1(~R- 5 )5.7))ReferenceVashenyuk etal. 2005Belov et al.2005Flückigeret al.2005Bieber et al.2005

20 January 2005.Numerical solutionof the F.-P. equationFor particle transport:The injection function hasonly 1 maximum.1. λ 1 =0.9±0.1 AU, q 1 ≈0.5;q ist the index in power spectrumof the fluctuating field2. wave excitation bySEP passage;3. λ 2 =0.6±0.1 AU, q 2 ≈1.5From Sáiz A., Ruffolo D., Rujiwarodom M. , John W.Bieber J.W. , Clem J., Evenson P. , Pyle P. , DuldigM.L. , Humble J.E. (29 th ICRC, 2005)

20 January 2005. Resume I‣ First arriving SEPs had very sharp angulardistribution and very hard energy spectrum.‣ First particles came scatter-free from ~40~(geo)40°S, ~40°W‣ In ~ 5-105min angular distribution became wider;spectrum, softer, SEP source shifted to East.‣ Changes in the observed spectrum may becaused by different sources (Vashenyuket al.)or by the transport in the changing interplanetarymedium (Sáiz et al.).

Timing of 20 Jan. 2005X7.1/2B, N12W58, AR 10720, 0636 – 0701 - 0726 UTSONG: gamma E>200-300 MeV 0645 – 0649 UTHX (RHESSI)max 0646±1 min0.8-7 MeV max 06474-7 MeV (incl.γ-lines) start 0644, max 0646Type II start 064415.4 GHz (n~3x10 12 cm -3 ) max 0644Relativistic protons arrived at the Earth at 0649 UTand peaked at 0654± 2 min

20 January, 2005, first arriving particles3.E+0559002.E+054900J(el),cm -2 s -1 sr -1 MeV -12.E+051.E+055.E+04390029001900900NM South Pole, %0.E+006 6.5 7 7.5 8U sw =800 km/s,L=1.05 AU20 Jan. 2005, UTEl, 175-315 keV, ACENM South Pole-100P,2 GeVβδT, , min0.95 9.2El,0.74250 keV 11.8

Gopalswamyet al. (29 th ICRC,)Left: SOHO’s LASCO (06:30) and EIT (06:36) difference imagessuperposed. No CME in the LASCO image but the EIT image shows theearly phase (arrow) of the 2005 January 20 CME.Middle: LASCO CME at 06:54 UTRight: CME height-time (diamonds with dashed line), GLE intensity (dottedlines, Oulu) and GOES soft X-ray light curve (solid line). The squarerepresents the inferred CME height from the EUV disturbance at 06:48 UT.The last LASCO height may be an underestimate due to ‘snow storm’.

Gopalswamy et al., 2005Simmnett and Roelof, 2005:CME speed ~ 2500 km/sMewaldt et al., 2005:CME speed~ 2500 km/s

Height, solar radii abovephotosphere76543210EarthSun06:00 07:00Time, UT20 January 2005. TimingX_start_max_endGam>200 MeV_SONG,startType II, startSouthPoleGLE_onset,South PoleGLE_m ax,South Poleel 175-315,ACE,startCME_Height(Gopalsw amy et al.)CME_Height(Mewaldt, Simnett)LASCOHeight of CME at the moment of relativistic protons release is~2.0-2.3 Rs, at the moment of the 1 st max H is ~3-3.1 Rs. For GLEs,mean values are 3.5 Rs and 11.5 Rs, respectively. (Gopalswamy et al.,2005)Height of CME at the moment 175-315 keV electron’s release is~3.4 Rs.

Protons have to be accelerated up torelativistic energies before 06:40 SolarTime, i.e. when CME was lower than 2-22.3 Rs.Prompt appearance of the high-energyparticles requires that a strong shockwith a large compression ratio occursvery early and relatively close to theSun (

20 January 2005. Resume II‣ SEPs were generated simultaneously with particles interacted onthe Sun.‣ Acceleration process was short and not consistent with the CME-driven shock acceleration (Mewaldtet al., Simnett & Roelof, , 2005)‣ First arrived relativistic particles were least of all influenced d bypropagation effects and could provide information on theacceleration mechanism, at least about several first minutes ofacceleration.‣ The first arrived particle spectrum of the 20 January 2005 event islikely a result of the acceleration in the DC electric fields orstochastic scattering with fast shock waves or Alfvén wavesgenerated at the magnetic reconnection site.

Integral energy spectra of solar protons for themost powerful solar energetic particle events1.E+061.E+051.E+041.E+03Jmax(>E), cm -2 s -1 sr -11.E+021.E+011.E+001.E-011.E-024 Aug. 197229 Sept.19891.E-03 19 Oct. 198923 Mar. 19911.E-0428 Oct. 20031.E-05 23 Feb. 1956(M)20 Jan. 20051.E-061.E+00 1.E+01 1.E+02 1.E+03 1.E+04 1.E+051 2 5Rigidity, GVEnergy, MeV

CONCLUSION‣ Energy spectra of SEPs in the large events are stronglyaffected by particle-wave interaction leading to Alfvén waveamplification and fluxes distortion.‣ The “time-of-maximum” spectrum in the large SEP eventsseems not to reflect acceleration on the Sun. However it isimportant as a convenient event characteristic, especially forthe applied aspects.‣ The first to arrive energetic particles can give an insight in thesolar processes. Timing is very important from bothobservational and modeling points of view.‣ The first to arrive particle spectrum of the 20 January 2005event is likely a result of the acceleration in the DC electricfields or stochastic scattering with fast shock waves or Alfvénwaves generated at the magnetic reconnection site.

AcknowledgementI would like to express mysincere gratitude to all theauthors whose results wereused for this overview.