Improved SOT (Hinode mission) high resolution solar imaging observations

  • H. GoodarziEmail author
  • S. Koutchmy
  • A. Adjabshirizadeh
Original Article


We consider the best today available observations of the Sun free of turbulent Earth atmospheric effects, taken with the Solar Optical Telescope (SOT) onboard the Hinode spacecraft. Both the instrumental smearing and the observed stray light are analyzed in order to improve the resolution. The Point Spread Function (PSF) corresponding to the blue continuum Broadband Filter Imager (BFI) near 450 nm is deduced by analyzing (i) the limb of the Sun and (ii) images taken during the transit of the planet Venus in 2012. A combination of Gaussian and Lorentzian functions is selected to construct a PSF in order to remove both smearing due to the instrumental diffraction effects (PSF core) and the large-angle stray light due to the spiders and central obscuration (wings of the PSF) that are responsible for the parasitic stray light. A Max-likelihood deconvolution procedure based on an optimum number of iterations is discussed. It is applied to several solar field images, including the granulation near the limb. The normal non-magnetic granulation is compared to the abnormal granulation which we call magnetic. A new feature appearing for the first time at the extreme- limb of the disk (the last 100 km) is discussed in the context of the definition of the solar edge and of the solar diameter. A single sunspot is considered in order to illustrate how effectively the restoration works on the sunspot core. A set of 125 consecutive deconvolved images is assembled in a 45 min long movie illustrating the complexity of the dynamical behavior inside and around the sunspot.


Telescopic PSF Stray-light Solar granulation Solar atmosphere Sunspot umbral dots 



Hinode is a Japanese mission developed and launched by ISAS/JAXA, collaborating with NAOJ as a domestic partner, NASA and STFC (UK) as international partners. Scientific operation of the Hinode mission is conducted by the Hinode science team organized at ISAS/JAXA. This team mainly consists of scientists from institutes in the partner countries. Support for the post-launch operation is provided by JAXA and NAOJ (Japan), STFC (UK), NASA, ESA, and NSC (Norway). The work of H.G. is supported by an award of the French Embassy in Teheran. We thank P.-A. Lhote, L. Vigroux and F. Bernardeau for their constant interest and support. We thank Hassan Fathivavsari, Jean-Claude Vial, Frederic Baudin and specially Leon Golub for providing a critical reading of the paper. Finally we want to thank our referee for pointing out excellent remarks that permitted to significantly improve the paper.

Supplementary material

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  1. Adjabshirzadeh, A., Koutchmy, S.: Sol. Phys. 75, 71 (1982) ADSCrossRefGoogle Scholar
  2. Adjabshirzadeh, A., Koutchmy, S.: Astron. Astrophys. 122, 1–8 (1983) ADSGoogle Scholar
  3. Aime, C.: Astron. Astrophys. 467, 317–325 (2007) ADSCrossRefGoogle Scholar
  4. Baudin, F., Molowny-Horas, R., Koutchmy, S.: Astron. Astrophys. 326, 842 (1997) ADSGoogle Scholar
  5. Bazin, C., Koutchmy, S.: J. Adv. Res. 4(3), 307–313 (2013) CrossRefGoogle Scholar
  6. Bracewell, R.N.: The Fourier transform and its applications. McGraw-Hill International editions (1976) Google Scholar
  7. DeForest, C.E., Martens, P.C.H., Wills-Davey, M.J.: Astrophys. J. 690, 1264 (2009) ADSCrossRefGoogle Scholar
  8. Dunn, R.B., Zirker, J.: Sol. Phys. 33(2), 281–304 (1973) ADSGoogle Scholar
  9. Fathivavsari, H., Ajabshirizadeh, A., Koutchmy, S.: Astrophys. Space Sci. 353(2), 347–355 (2014). See also VizieR Online Data Catalog: 398–710 nm Sun spectral atlases in Simbad (2014) ADSCrossRefGoogle Scholar
  10. Gadun, A.S.: Kinemat. Phys. Celest. Bodies 11(3), 54 (1995) Google Scholar
  11. Johnson, C.B.: Appl. Opt. 12, 1031 (1972) ADSCrossRefGoogle Scholar
  12. Koutchmy, S.: Astron. Astrophys. 61(3), 397–404 (1977) ADSGoogle Scholar
  13. Koutchmy, S.: In: Rabin, D.M., et al. (eds.) Infrared Solar Physics. IAU Symp., vol. 154, pp. 239–250 (1994) CrossRefGoogle Scholar
  14. Koutchmy, S., Koutchmy, O.: Astron. Astrophys. Suppl. Ser. 13, 295 (1974) ADSGoogle Scholar
  15. Koutchmy, O., Koutchmy, S.: In: von der Luhe, O. (ed.) Proc. of 10th Sacramento Peak Summer Workshop, High Spatial Resolution Solar Observations (Sunspot, NSO), p. 217 (1989) Google Scholar
  16. Koutchmy, S., Koutchmy, O., Kotov, V.: Astron. Astrophys. 59, 189 (1977) ADSGoogle Scholar
  17. Lites, B.W.: Sol. Phys. 85, 193–214 (1983) ADSCrossRefGoogle Scholar
  18. Louis, R.E., Mathew, S.K., Bellot Rubio, L.R., Ichimoto, K., Ravindra, B., Raja Bayanna, A.: Astrophys. J. 752, 109 (2012) ADSCrossRefGoogle Scholar
  19. Mathew, S.K., Zakharov, V., Solanki, S.K.: Astron. Astrophys. 501, L19–L22 (2009) ADSCrossRefGoogle Scholar
  20. Molowny-Horas, R.: Sol. Phys. 154, 29–39 (1994) ADSCrossRefGoogle Scholar
  21. Richardson, W.H.: J. Opt. Soc. Am. 62, 55 (1972) ADSCrossRefGoogle Scholar
  22. Rosen, W.A., Poss, H.L.: Sol. Phys. 78, 17–27 (1982) ADSCrossRefGoogle Scholar
  23. Rozelot, J.P., Fazel, Z.: Sol. Phys. 287(1–2), 161–170 (2013) ADSCrossRefGoogle Scholar
  24. Rutten, R.J.: The solar atmosphere, Special issue in celebration of C. de Jager’s 80th birthday, Eds. Sterken and van der Hucht. J. Astron. Data 8(8) (2002) Google Scholar
  25. Sechi, A.: Le Soleil. Gauthier-Villars, Paris (1870) Google Scholar
  26. Sobotka, M., Puschmann, K.G.: Astron. Astrophys. 504, 575–581 (2009) ADSCrossRefGoogle Scholar
  27. Solov’ev, A., Kirichek, E.: Astrophys. Space Sci. 352, 23–42 (2014) ADSCrossRefGoogle Scholar
  28. Suematsu, Y., Tsuneta, S., Ichimoto, K., Shimizu, T., Otsubo, M., Katsukawa, Y., Nakagiri, M., Noguchi, M., Tamura, T., Kato, Y., et al.: Sol. Phys. 249, 197–220 (2008) ADSCrossRefGoogle Scholar
  29. Tavabi, E., Koutchmy, S.: Astrophys. Space Sci. 352(1), 7–15 (2014) ADSCrossRefGoogle Scholar
  30. Tavabi, E., Koutchmy, S., Ajabshirzadeh, A.: New Astron. 16(4), 296–305 (2011) ADSCrossRefGoogle Scholar
  31. Tavabi, E., Koutchmy, S., Ajabshirzadeh, A.: Sol. Phys. 283(1), 187–194 (2013) ADSCrossRefGoogle Scholar
  32. Tsuneta, S., Ichimoto, K., Katsukawa, Y., et al.: Sol. Phys. 249, 167–196 (2008) ADSCrossRefGoogle Scholar
  33. Vernazza, J.E., Avrett, E.H., Loeser, R.L.: Astrophys. J. Suppl. Ser. 30, 1–60 (1976) ADSCrossRefGoogle Scholar
  34. Wedemeyer-Böhm, S.: Astron. Astrophys. 487, 399 (2008) ADSCrossRefGoogle Scholar
  35. Wedemeyer-Böhm, S., Rouppe van der Voort, L.: Astron. Astrophys. 503, 225–239 (2009) ADSCrossRefGoogle Scholar
  36. Yeo, K.L., Feller, A., Solanki, S.K., Couvidat, S., Danilovic, S., Krivova, N.A.: Astron. Astrophys. 561, A22 (2014) ADSCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.Department of Theoretical Physics and Astrophysics, Faculty of PhysicsUniversity of TabrizTabrizIran
  2. 2.Institut d’Astrophysique de Paris UMR 7091CNRS and UPMC (Sorbonne Univ.)ParisFrance

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