NBYM 2006 A major proton event of 2005 January 20: propagating supershock or superflare? V. Grechnev 1, V. Kurt 2, A. Uralov 1, H.Nakajima 3, A. Altyntsev 1, L. Kashapova 1, N. Meshalkina 1 et al. 1 Institute of Solar-Terrestrial Physics, Irkutsk 2 Moscow State University, Moscow 3 Nobeyama Radio Observatory, Nobeyama

The event of 2005 January 20 Speedest (>5000 km/s) CME ever registered with 4.4R  (06:54 UT) Protons >700 cm -2 s -1 sr -1 with E>100 MeV came soon GLE of 277 %, largest in the 23 th cycle  -ray emission X7.1/2B Microwave flux ~ 10 5 sfu SXR Protons

Problem in question Gopalswamy et al. (2005, 29 th ICRC, 101): common shock origin for type II radio bursts and GLEs Simnett (2006, A&A 445, 715): CME was not responsible for the relativistic ion acceleration ¿Where high-energy protons were accelerated?

Available data The event observed in X-rays and  -rays: Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) non-imaging Solar Neutron and Gamma spectrometer (SONG) on board CORONAS-F spacecraft from 06:43:30 on  -rays up to 100 MeV TRACE in 1600 Å line from 06:53:30 on Nobeyama Radio Polarimeters (NoRP) No NoRH observations (too late)

HXR and  -ray time profiles TRACE RHESSI SONG HXR and  -ray time profiles

RHESSI/HXR & SXR, TRACE 1600 Å Background: TRACE 1600 Å. No images between 06:18 and 06:52:30 Red: RHESSI SXR Blue: RHESSI HXR ( kev?) GOES/SXI: Movie:

Comparison of TRACE 1600 Å and HXR keV images One can expect correlation of bright kernels in TRACE 1600 Å and HXR This can be used for coalignment The interval of 06:52:30-06:57 Variance and averaged images  06:52 06:5706:47

Ribbons in TRACE 1600 Å images Variance map Time profiles Averaged image

Outcome from TRACE 1600 Å images: 8 bright kernels at the outer parts of ribbons 4 regions with well-pronounced counterparts  4 loops: Formation of a usual (low) arcade Try to compare with RHESSI keV images 

Comparison of 1600 Å and HXR bright kernels White: keV kernels Black: 1600 Å kernels Bottom: shift +7 .5, -10 .5  satisfactory coalignment Now we can find relative positions of sunspots, ribbons, and X-ray sources 

Relative positions of sunspots, ribbons, and X-ray sources Ribbons crossed sunspots Large SXR loop-like structure White Light 6-12 keV keV 1600 Å ribbon

keV RHESSI images N-footpoint fixed S-footpoint moves eastwards HXR are weaker from N-footpoint  B N-foot > B S-foot, N-footpoint needs more counterparts N S

Evolution of AR Magnetograms: one week of SOHO/MDI observations, Jan All images “co- rotated” to Jan 15, 00 UT  B > 2000 G in N- polarity sunspot B = 1800 G overturn

NoRP data Note: Y scales in 10 3 sfu Stokes I Stokes V Source A Source B

NoRP spectra peak, GHz   Flux, 10 3 sfu Frequency, GHz

NoRP data suggest Source A: 35 GHz 2000 G Source B: peak < 35 GHz in S-polarity region, first in weaker sunspot, then moved eastwards One or two more sources in weaker magnetic fields   -( )    Microwave emission was produced by large amount of hard electrons in strong magnetic fields Source B Source A

SXR GOES data Loop: h=50 Mm, l=2.6 Mm, d=0.9 Mm, V=8·10 27 cm 3 Neupert effect & trapping: GOES 12 GOES 10 GOES/SXI  keV 34 GHz 17 GHz d/dt(GOES 1-8 Å) Ne T EM

Features of the event Long bundle of loops rooted in sunspots Trapping & harder microwaves  large mirroring expectable in a large loop Many accelerated particles (estimated from microwave fluxes) Strong magnetic fields

HXR &  -ray images and spectrum  = 2.7 – softer than microwaves suggest Nuclear lines 0.51 & 2.2 MeV All images are confined to the active region

Ground-Level Enhancement Perfect coincidence No dispersion with respect to  -rays Delay of ~380 s Solar wind disturbed (ACE: ~800 km/s) - path length longer Leading edge was a bunch of ultrarelativistic protons

Conclusion 2.2 MeV line is due to collisions of MeV-energy protons with dense layers The 2.2 MeV source image is located in region of closed magnetic structures Protons from remote outer source have no access into the closed structures in AR  Protons could be accelerated only in AR On the other hand, protons accelerated in the current sheet are injected both down and up, and the latter reach the Earth to produce GLE

Was this event exceptional? Date Peak 35 GHz 80 GHz Protons GLE Position Flare L&B Gopal : No data N32E57 X : N35W36 X : S26E28 X : ? S28W60 X : ? N32W85 X : N30E65 X : N33E44 X : N34E04 X : N31W17 X : S15E60 X : % S23W90 X : Weak 1% N17W78 X : S13E72 X : % S02W81 X : % N14W61 X :28 weak weak strong N20W66 M : % S23W92 C : % N07W62 M7.1 + F 35 > 10 4 sfu  15 of 649 events

Summary High-energy protons in 2005 January 20 event were accelerated on the Sun, within the active region 2005 January 20 event was a major proton flare Moreover, it was a typical major proton flare Microwave emission in such events is generated by large number of electrons with hard spectrum in strong magnetic fields

We acknowledge Shibasaki San and NSRO for the opportunity to work here under perfect conditions Staff members of the NSRO for the hospitality