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The goal of the study : To localize sources of the quasi-stationary slow solar wind. Method:

PROBA 2 Guest Investigator project (2010-2012) EUV imaging of the solar corona and study of slow solar wind streams. V . Slemzin 1 , L. Harra 2 , S. Kuzin 1 , A. Urnov 1 , F. Goryaev 1 , 1 LPI, Russia, 2 MSSL/UCL PROBA 2/SWAP team. The goal of the study :

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The goal of the study : To localize sources of the quasi-stationary slow solar wind. Method:

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  1. PROBA 2 Guest Investigator project (2010-2012)EUV imagingofthesolarcoronaandstudyofslowsolarwindstreams V. Slemzin1, L. Harra2, S. Kuzin1, A. Urnov1, F. Goryaev1, 1LPI, Russia, 2MSSL/UCL PROBA 2/SWAP team

  2. The goal of the study : • To localize sources of the quasi-stationary slow solar wind. • Method: • Some of the sources may be localized by outflows from active regions detected by the Doppler spectroscopy, their signatures in the corona co-aligned with open field lines and imprints in the slow solar wind. • Coronal signatures: fan rays at the disk and extended coronal rays at the limb. • First part of the study (2010-2011) : • imaging of the solar corona with SWAP • detection of outflows at the disk with Hinode/EIS • identification of coronal signatures of outflows • search of imprints of outflows in the solar wind data.

  3. 1. Wide FOV imaging of the inner corona with SWAP 3. Straylight subtraction using the eclipse images 1. Paving ±10’ Straylight model (linear Log fit to the radial distribution at R>2Rsun) 4. Combination of a mosaic image 2. Summation of 80-90 images in each position Cadence 30 s Full time of observation ~ 3h

  4. 08 July 2010 The length of coronal rays is defined by Ne at the base and radial velocity. If V≥ 60 km/s, the rays are not seen at R>1.5Rsun due to Doppler dimming 20 October 2010 21 October 2010 8 July 2010 1.94 Rsun 01 Dec 2010 2.10 Rsun

  5. AIA vs SWAP AIA 171 September 12, 2011 SWAP 174

  6. AIA 171 A: - Limited FOV - Higher resolution • SWAP 171 A: • Wider FOV • lower straylight

  7. 2. Detection of outflows with Hinode/EIS SWAP EIS, October 15, 2010 Outflow downflow AR 11112 PFSS Zoomed SWAP and PFSS in the EIS FOV

  8. 3. Coronal rays as main signatures of outflows

  9. SWAP, March 23, 2011 SWAP April 6, 2011 AR 11176 EIS, March 23, 2011 EIS, April 4, 2011 Outflow region Outflow region

  10. PFSS April 6, 2011 LASCO and SWAP polar images at W-limb (April 6, 2011) LASCO C2, April 6, 2011 The streamer corresponds to the outflow position at the limb

  11. 4. Imprints of outflows in the solar wind data (October 2010) Positions of STEREO A , - B , ACE and WIND on 2010-10-15 12:00 UT Oct 13-14 Δt=4.3d Oct 26-29 Δt=6.3d Oct 18-19 Δt=4.2d Oct 15, 2010 Variation of the solar wind flux correlates with temporal evolution of the AR ACE/WIND

  12. Conclusion • It was shown that outflows in active regions detected at the disk in the Fe lines with Texc~1 MK canproduce extended coronal structurescoaligned with open field lines and imprints in the slow solar wind. • Publication: Slemzin , Harra et al. Submitted To Solar Phys. • Two main advantages of SWAP to detect coronal signatures of the plasma flows: • Large field of view • Wavelength band 174 A (FeIX-X) is optimal to see structures with T~1MK responsible for plasma transit from the Sun to the solar wind . It is confirmed by domination of the FeXI ions in the solar wind (Habbal et al. 2007, 2010)

  13. Second part of the study (2011-2012): Long term evolution of the EUV corona. Comparison of coronal and magnetic synoptic maps N 0 90 270 180 S

  14. Polar movie of the corona during 1 rotation

  15. Variation of the synoptic maps of the corona with distance R=1.00 – 1.67 Rsun

  16. 3. Comparison with the WSO synoptic maps of magnetic field. R=1.00 Rsun Photospheric field

  17. R=1.66 Rsun Source surface at 2.5 Rsun Lee et al. 2011: In the min of 22-23 cycles SS is located at 1.9 – 1.5 Rsun

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