Abstract
Measurements of the Sun in the near-infrared He i 10830 Å absorption line were performed using the echelle spectrograph with a dispersion of 6.71 mÅ per pixel at the Vacuum Tower Telescope (German Solar Telescopes, Teide Observatory, Izaña, Tenerife, Spain) on May 26, 1993. These measurements were compared with full-disc soft X-ray images of the Sun (Japanese solar satellite Yohkoh), full-disc solar images in Hα (Big Bear Solar Observatory), full-disc solar images in the He i 10830 Å line (National Solar Observatory, Kitt Peak) and with full-disc microwave solar maps at 37 GHz (Metsähovi Radio Research Station). In the He 10830 Å line the Sun displays a limb darkening similar to that in the visible part of the spectrum. Active regions and Hα filaments show a strong absorption in the He 10830 Å line, whereas the absorption is weak in coronal holes.
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Avrett, E. H., Fontenla, J. M., and Loeser, 1994, in D. M. Rabin et al. (eds.), ‘Infrared Solar Physics’, IAU Symp. 154, 35.
Borovik, V. N. and Kurbanov, M. Sh.: 1990, Astron. Nachr. 311, 371.
Brajša, R.: 1993, Solar Phys. 144, 199.
Brajša, R., Ruždjak, V., Vršnak, B., Pohjolainen, S., Urpo, S., and Wöhl, H.: 1994, Hvar Obs. Bull. 18, 9.
de Jager, C., Namba, O., and Neven, L.: 1966, Bull. Astron. Inst. Netherlands 18, 128.
Fleck, D., Deubner, F.-L., Maier, D., and Schmidt, W.: 1994, in D. M. Rabin et al., ‘Infrared Solar Physics’, IAU Symp. 154, 65.
Habbal, S. R. and Gonzalez, R. D.: 1991, Astrophys. J. 376, L25.
Harvey, K. L.: 1994, in D. M. Rabin et al., (eds.), ‘Infrared Solar Physics’, IAU Symp. 154, 71.
Harvey, J. W. and Livingston, W. C.: 1994, in D. M. Rabin et al. (eds.), ‘Infrared Solar Physics’, IAU Symp. 154, 59.
Hirth, W. and Fürst, E.: 1976, Mitt. Astron. Ges. 38, 208.
Jones, H. P.: 1992, in K. L. Harvey (ed.), ‘The Solar Cycle’, The NSO/Sac. Peak 12th Summer Workshop, ASP Conf. Ser. 27, 315.
Jones, H. P., Duvall, T. L., Jr., Harvey, J. W., Mahaffey, C. T., Schwitters, J. D., and Simmons, J. E.: 1992, Solar Phys. 139, 211.
Kosugi, T., Ishiguro, M., and Shibasaki, K.: 1986, Publ. Astron. Soc. Japan 38, 1.
Mohler, O. C. and Goldberg, L.: 1956, Astrophys. J. 124, 13.
Rüedi, I., Solanki, S. K., and Livingston, W. C.: 1994, in M. Schüssler and W. Schmidt (eds.), Solar Magnetic Fields, Cambridge University Press, Cambridge, p. 363.
Sakurai, T., Wöhl, H., Brajša, R., Pohjolainen, S., Ruždjak, V., Urpo, S., Vršnak, B., and Ichimoto, K.: 1994, in J. Manninen and L. Kalliopuska (eds.), Vth COSPAR Meeting of the Finnish Space Scientists, University of Oulu, Department of Physics, Report 124, p. 53.
Schmidt, W., Knölker, M., and Westendorp-Plaza, C.: 1994, Astron. Astrophys. 287, 229.
Shcherbakov, A. G. and Shcherbakova, Z. A.: 1991, in I. Tuominen, D. Moss, and G. Rüdiger (eds.), ‘The Sun and Cool Stars: Activity, Magnetism, Dynamos’, IAU Colloq. 130, Lecture Notes in Physics 380, 252, Springer-Verlag, Berlin.
Tsuneta, S., Acton, L., Bruner, M., Lemen, J., Brown, W., Caravalho, R., Catura, R., Freeland, S., Jurchevich, B., Morrison, M., Ogawara, Y., Hirayama, T., and Owens, J.: 1991, Solar Phys. 136, 37.
Urpo, S., Pohjolainen, S., and Teräsranta, H.: 1994, Solar Observations at Metsähovi in 1993, Helsinki University of Technology, Metsähovi Radio Research Station, Series A, Report 16.
Zirin, H.: 1992a, in J. T. Schmelz and J. C. Brown (eds.), ‘The Sun: a Laboratory for Astrophysics’, NATO ASI Ser. C373, Kluwer Academic Publishers, Dordrecht, Holland, p. 449.
Zirin, H.: 1992b, in J. T. Schmelz and J. C. Brown (eds.), ‘The Sun: a Laboratory for Astrophysics’, NATO ASI Ser. C373, Kluwer Academic Publishers, Dordrecht, Holland, p. 175.
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Brajša, R., Pohjolainen, S., Ruždjak, V. et al. Helium 10830 Å measurements of the Sun. Sol Phys 163, 79–91 (1996). https://doi.org/10.1007/BF00165457
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DOI: https://doi.org/10.1007/BF00165457