EUV Blast Waves in Impulsive Solar Energetic Particle Events

Transcription

1 EUV Blast Waves in Impulsive Solar Energetic Particle Events Radoslav Bučík D. E. Innes, L. Guo G.M. Mason (JHU/APL) M. E. Wiedenbeck (Caltech/JPL) X-ray: NASA/CXC/SAO/T.Temim et al. and ESA/XMM- Newton Radio: SIFA/MOST and CSIRO/ATNF/ATCA; Infrared: UMass/IPAC-Caltech/NASA/NSF/2MASS MPS SGS

2 in April 2015 submitted to ApJ Letters poster at 14 th Annual International Astrophysics Conference: Linear and Nonlinear Particle Energization throughout the Heliosphere and Beyond news in NASA Heliophysics Senior Review presentation

3 LSEP events Two SEP sources ISEP events Reames SSRv (2013) shock acceleration signatures (observed) power law energy spectra; intensity peaks at ICME shocks CME Shock signatures type II radio bursts, ejecta envelopes in EUV & white light, jumps in SW acceleration mechanism unknown resonant interaction with (reconnection generated) plasma waves and/or reconnection exhaust ion heating signatures of magnetic reconnection in ISEP events EUV jets

4 2-10 MeV/n 3 He-rich events \ corona abund. ISEP ( 3 He-rich) events anomalous abundances enhanc. f. >10 4! markedly different from solar system enhanc. f. 10 enhanc. f. 2-3 acceleration mechanism - enormously enhances rare 3He & ultra heavies but not H, 4He, C, N, O (e.g., Mason et al. 1986, 2004) unenhanced (3 MK) Ne, Mg heavier isotopes (22Ne, 26Mg) are enhanced (Mason et al. 1994; Wiedenbeck et al. 2010) Reames & Ng ApJ (2004) 4

5 EUV coronal waves & LSEP events (early) SEP injection associated with arrival of EUV wave at s/c connected field lines low in the corona (e.g., Krucker et al. ApJ, 1999; Torsti et al. ApJ, 1999; Nitta AIP Proc. Conf. 2012, Rouillard et al. ApJ, 2012; Park, Innes, Bucik et al. ApJ, 2013, 2015) but some studies concluded - longitudinal expansions of SEPs not controlled by EUV waves (e.g., Prise et al. SoPh, 2014; Lario et al. ApJ, 2014)

6 EUV coronal waves & LSEP events Aug 14 LSEP event SDO STEREO-A X B X L1 X A Nitta (2012)

7 STEREO-A Park et al. ApJ (2013) L1 STEREO-B e - e - Aug 14 LSEP event rapid increase on L1, delay on STEREO-B & low intensities + gradual increase on STEREO-A - explained by EUV wave propagation/ properties at s/c lowcoronal foot-point e - Aug 2010

8 Coronal phenomena associated with ISEP events EUV and white-light jets in ISEP events (Wang et al. ApJ, 2006; Nitta et al. ApJ, 2006, 2008; Bucik, Innes et al. ApJ, 2014, Chen, Bucik, Innes et al., A&A, 2015) - interpreted to be a signature of interchange magnetic reconnection following by model of Shibata et al. PASJ, 1992 narrow & fast CMEs surprisingly associated with some ISEPs (Kahler et al. ApJ, 2001; Nitta et al. ApJ, 2006) (non CME) EUV waves associated with ISEPs (Bucik, Innes, Guo et al. ApJL, 2015 submitted) THIS WORK

9 Kahler et al. ApJ (2001) CMEs associated with ISEP events

10 Coronal phenomena associated with ISEP events EUV and white-light jets in ISEP events (Wang et al. ApJ, 2006; Nitta et al. ApJ, 2006, 2008; Bucik, Innes et al. ApJ, 2014; Chen, Bucik, Innes et al., A&A, 2015) - interpreted to be a signature of interchange magnetic reconnection following by model of Shibata et al. PASJ, 1992 narrow & fast CMEs surprisingly associated with some ISEPs (Kahler et al. ApJ, 2001; Nitta et al. ApJ, 2006) (non CME) EUV waves associated with ISEPs (Bucik, Innes, Guo et al. ApJL, 2015 submitted) THIS WORK

11 3 He-rich SEP events 2010 Jan Feb 2 type III MeV/n MeV/n AMU MC

12 MC-like structure B slightly enhanced MC N decreasing T no depressed T expected

13 3 He-rich SEP events SIT / STEREO-A STEREO- 3 He Feb 2

14 Energy spectra 3 He, 4 He, O, Fe similar power laws (class-1) 4 He, O similar power laws; 3 He, Fe distinctly flatter at low energies (class-2)

15 Spectral classes of 3 He-rich SEPs Class-1 event Class-2 event Mason et al. ApJ (2000) Class-1 events further stage of acceleration (Mason et al. ApJ, 2000, 2002) by CME shocks (?) (Petrosian et al. ApJ, 2009) Class-2 events - basic mechanism of 3He enrichment (Mason et al. ApJ, 2000, 2002)

16 Liu et al. ApJ (2006) Stochastic Acceleration (SA) Class-2 event SA model by parallelpropagating waves gives reasonable fit to the class-2 spectra (3He, 4He) class-1 spectra not yet modeled (but power laws - produced by shock acceleration) no shocks indications in 3He-rich SEPs (in radio or optical observations) could EUV waves be such a proxy?

17 Magnetic connection Jan 26 event PFSS model coronal field

18 EUV Wave Jan 26 event 1042 L1 the wave speed ~300 km/s (typical) comparable with quiet-sun magnetosonic speeds (Thompson & Myers ApJS, 2009) waves could be faster at early stages and may be even shocks (Warmuth & Mann A&A, 2011; Nitta et al. ApJ, 2013)

19 EUV Wave Jan 26 event flare driven wave

20 EUV Wave driven by CME - example >100 MeV GOES p

21 EUV Wave driven by CME - example

22 Jan 26 event - no CME wave? narrow stream (very poor event in SOHO LASCO CME catalog) Frames shown: 17:06, 17:30, 17:54, 18:06, 18:30

23 EUV Wave Feb 2 event STA less sharp and less bright fronts than Jan 26 wave

24 EUV Wave Feb 2 event

25 Feb 2 event - no CME weak outflow (not marked in COR1 CME list) Frames between 11:35 and 12:50 UT

26 Summary the first report of a large-scale EUV coronal wave observed in association with 3He-rich SEPs new viewing angles + high EUVI cadence + low solar activity allowed to found such association the waves triggered by minor flares; appeared concurrently with EUV jets & type III bursts but without CMEs & type II EUV waves may modify energy spectra of 3He-rich SEPs bright wave in the Jan 26 event could modify the original curved spectra more diffused wave in the Feb 2 event might not affect the spectral forms could these waves generate/enhance turbulence required for 3He-rich acceleration models?

27 Further (possible) work searching for other cases (e.g., Dec 22, 2009) - easier found during periods of low solar activity; for L1 events waves investigate with STEREO-A and for STEREO-B events with SDO simulated blast waves (Lijia Guo - MPS) & effect on the curved spectra

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