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Microwave, EUV, and X-ray Observations of Active Region Loops and Filaments

Published online by Cambridge University Press:  14 August 2015

E. Schmahl*
Affiliation:
Astronomy Program, University of Maryland College Park, Maryland

Extract

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In the early years of centimetric radio astronomy, even before high resolution techniques were available, it was found that the apparent brightness temperature of the full disk is made up of a background level (the so-called quiet sun temperature) added to which is a contribution roughly proportional to the sum of the sunspot areas on the disk (Smerd 1964, Pawsey and Smerd 1953). Eclipse observations in 1946 at a wavelength of 10.7 cm (Covington 1947) and in 1948 at 10 cm (Piddington and Hindman 1949) and at 3.2 cm (Hagen et al. 1948) showed that the average bright area occupied about 4-thousandths of the disk, and had brightness temperatures of about 5 million degrees. Subsequent interferometric observations have extended and amplified these early studies in several ways. Kundu (1965) has reviewed the literature up to the early 1960's.

Type
Session II - Active Regions
Copyright
Copyright © Reidel 1980 

References

Akhmedov, Sh., Borovik, V., Ikhsanova, V., Nagibeda, V., and Peterova, N.: 1976, Sov. Astron. 20, 460.Google Scholar
Alissandrakis, C.: 1977 , University of Maryland.Google Scholar
Alissandrakis, C., Kundu, M. and Lantos, P.: 1979 Astron. Astrophys. (in press).Google Scholar
Boldyrev, S., Ipatova, I., Ipatova, A., Peterova, N.: 1978, Sov. Astron. 4, 251.Google Scholar
Bartoe, J.-D., Brueckner, G. and Van Hoosier, M.: 1979, Bull. Am. Astron. Soc. 11, 397, (abstract).Google Scholar
Bray, R. and Loughhead, R.: 1965, Sunspots, John Wiley and Sons: New York.Google Scholar
Bregman, J. and Felli, M.: 1976, Astron. Astrophys. 46, 41.Google Scholar
Brueckner, G.: 1976, in I.A.U. Colloq. No. 36; Nice, France.Google Scholar
Brueckner, G., Bartoe, J.-D. and Van Hoosier, M.: 1977, Proc. of the Nov. 1977 OSO-8 Workshop (ed. Hansen, E. and Schaffner, S.) Univ. of Color.: Boulder.Google Scholar
Bruner, E. Jr., Chipman, E., Lites, B., Rottman, G., Shine, R., Athay, R., White, O.: 1976, Astrophys. J. (Letters) 210, L97.Google Scholar
Bruns, A., Grechko, G., Gubanov, A., Klimuk, P., Sevastyanov, V., Serverny, A. and Steshenko, N.: 1977 in I.A.U. Colloq. No. 36; Nice, France.Google Scholar
Cheng, C. -C.: 1979 (preprint).Google Scholar
Cheng, C. -C. and Kjeldseth Moe, O.: 1977, Solar Phys. 52, 327.Google Scholar
Cook, J. and Nicolas, K.: 1979, Astrophys. J. 229, 1163.Google Scholar
Covington, A.: 1947, Nature 159, 405.Google Scholar
Deubner, F.: 1976, in I.A.U. Colloq. No. 36; Nice, France.Google Scholar
Dulk, G.: 1978, Am. Astron. Soc., Solar Phys. Div., Ann Arbor, Michigan.Google Scholar
Dupree, A.: 1978, in Advances in Atmoic and Molecular Physics 14 (eds. Bates, D. R. and Bederson, B.) Academic Press: New York.Google Scholar
Emslie, G. and Machado, M.: 1979 Center for Astrophysics Reprint No. 1034.Google Scholar
Efanov, V., Moiseev, I., Nesterov, N., Gel'freikh, G., Golnev, V., Korzhevin, A., Korol'kov, D., Akhmedov, Sh., Peterova, N., Abranin, A., Bazeljan, L., Avdjushin, S., Perejaslova, N., Fomichev, V., Chertok, I.: 1977 (preprint).Google Scholar
Felli, M., Poletto, G. and Rofani, G.: 1977, Solar Phys. 51, 65.Google Scholar
Foukal, P.: 1975, Solar Phys. 43, 327.Google Scholar
Foukal, P.: 1976, Astrophys. J. 210, 575.Google Scholar
Foukal, P.: 1978, Astrophys. J. 223, 1046.Google Scholar
Foukal, P., Huber, M., Noyes, R., Reeves, E., Schmahl, E., Timothy, J., Vernazza, J. and Withbroe, G.: 1974, Astrophys. J. (Letters) 193, L143.Google Scholar
Gabriel, A. and Jordan, C.: 1975, M.N.R.A.S. 173, 397.Google Scholar
Gel'freikh, G., Akhmedov, Sh., Borovik, V., Gol'nev, V., Korzhevin, A., Nagnibeda, V., Peterova, N.: 1979, Izv. Glavn. Astron. Obs. 185, 167.Google Scholar
Golub, L., Krieger, A., Harvey, J. and Vaiana, G.: 1977, Solar Phys. 53, 111.Google Scholar
Graf, W.: 1978, Am. Astron. Soc./S.P.D. Workshop on Flare Research and S.M.M. (abstract).Google Scholar
Hagen, J., Jackson, R., McEwan, R. and Strong, F.: 1948, U.S. Naval Res. Lab., reprint, March.Google Scholar
Kane, S. and Pick, M.: 1976, Solar Phys. 47, 293.Google Scholar
Kovalev, V.: 1978, Sov. Astron. Lett. 4, 175.Google Scholar
Kreiger, A., Paolini, F., Vaiana, G. and Webb, D.: 1972, Solar Phys. 22, 150.Google Scholar
Krieger, A., Timothy, A., Roeloff, E.: 1973, Solar Phys. 32, 81.Google Scholar
Krieger, A., Vaiana, G., Van Speybroeck, L.: 1971 in Solar Magnetic Fields (ed. Howard, ) I.A.U. Google Scholar
Kundu, M. R.: 1959, Ann. d'Astrophys. 22, 1.Google Scholar
Kundu, M. R.: 1965, Solar Radio Astronomy (Interscience, New York).Google Scholar
Kundu, M. R.: 1974, Proceedings of Committee of European Radio Astronomers, (Berne, Switzerland), Edited by Schanda, E., p. 21.Google Scholar
Kundu, M. R. and Alissandrakis, C.: 1975, Nature 257, 465.Google Scholar
Kundu, M. R., Becker, R. and Velusamy, T.: 1974, Solar Phys. 34, 185.Google Scholar
Kundu, M. R., Alissandrakis, C., Bregman, J. and Hin, A.: 1977, Astrophys. J. 213, 278.Google Scholar
Kundu, M. R., Schmahl, E. J. and Gerassimenko, M.: 1979, Astron. Astrophys. (in press).Google Scholar
Lang, K. and Willson, R.: 1979, Nature 278, 24.Google Scholar
Lemaire, et al.: 1977, I.A.U. Colloq. No. 43 (Imperial College London, 1977, July).Google Scholar
Little, S. and Krieger, A.: 1977, Bull. Am. Astron. Soc. 9, 341 (abstract).Google Scholar
Mätzler, C.: 1978, Astron. Astrophys. (submitted).Google Scholar
Maxson, C. and Vaiana, G.: 1977, Astrophys. J. 215, 919.Google Scholar
McIntosh, P., Krieger, A., Nolte, J. and Vaiana, G.: 1976, Solar Phys. 49, 57.Google Scholar
Nicolas, K., Bartoe, J.-D. Brueckner, G. and Van Hoosier, M.: 1979, Astrophys. J. (in press).Google Scholar
Noyes, R.: 1974, I.A.U. Colloq. No. 27, 18 (abstract).Google Scholar
Noyes, R.: 1976 in Frontiers of Astrophysics, pp. 4194 (ed. Avrett, E. H.) Harvard Univ. Press, Cambridge.Google Scholar
Noci, G.: 1973, Solar Phys. 28, 404.Google Scholar
Pallavicini, R., Vaiana, G., Tofani, G. and Felli, M.: 1979, Astrophys. J. 229, 375.Google Scholar
Pariiskii, Yu., Korol'kov, D., Shris, O., Kaidanovskii, N., Esepkina, N., Zverev, Yu., Stotskii, A., Akhmedov, Sh., Bogod, V., Bolyrev, S., Gel'freikh, G., Ipatova, I., Korzhavin, A. and Romantosov, V.: 1976, Sov. Astron. 20, 577.Google Scholar
Parker, E.: 1977, Ann. Rev. Astron. and Astrophys. 15, 45.Google Scholar
Pawsey, J. and Smerd, S.: 1953, Solar Radio Emission, The Sun, (ed. Kuiper, G., Chicago).Google Scholar
Piddington, J. and Hindmann, J.: 1949, Australian J. Sci. Res. A 2, 524.Google Scholar
Pneumann, G.: 1973, Solar Phys. 28, 247.Google Scholar
Poletto, G., Vaiana, G., Zombeck, M., Krieger, A., and Timothy, A.: 1975 Solar Phys. 44, 83.Google Scholar
Purcell, J. and Tousey, R.: 1969, Bull. Am. Astron. Soc. 1, 290.Google Scholar
Reeves, E., Timothy, J., Foukal, P., Huber, M., Noyes, R., Schmahl, E., Vernazza, J. and Withbroe, G.: 1976 (see Underwood, et al.).Google Scholar
Reidy, W., Vaiana, G., Zehnpfeenig, T. and Giacconi, R.: 1968, Astrophys. J. 151, 133.Google Scholar
Rosner, R., Tucker, W. and Vaiana, G.: 1978, Astrophys. J. 220, 643.Google Scholar
Salmonovich, A.: 1962, Sov. Astron. AJ 6, 202.Google Scholar
Schmahl, E. and Orrall, F.: 1979, Astrophys. J. (Letters) 231, L41.Google Scholar
Sheeley, N. Jr.: 1979, Solar Phys. (submitted) Google Scholar
Sheeley, N. Jr.: 1974, unpublished movies of NRL Skylab/ATM sepctro-heliograms.Google Scholar
Smerd, S.: 1964, Annals of the IGY, 34.Google Scholar
Swarup, G.: 1961, , Stanford University.Google Scholar
Svestka, Z., Solodyna, G., Howard, R., Levine, R.: 1977, Solar Phys. 55, 359.Google Scholar
Takakura, T.: 1967, Solar Phys. 1, 304.Google Scholar
Takakura, T. and Scalise, E.: 1970, Solar Phys. 11, 434.Google Scholar
Tousey, R., Bartoe, J.-D., Bohlin, J., Brueckner, G., Purcell, J., Scherrer, V., Sheeley, N. Jr., Schumacher, R., Van Hoosier, M.: 1973, Solar Phys. 33, 265.Google Scholar
Underwood, J. and Muney, W.: 1967, Solar Phys. 1, 129.Google Scholar
Underwood, J. et al.: 1976, in Progress in Astronautics and Aeronautics , V. 48 (ed. Kent, M., Stuhlinger, E., and Wu, S. T.) New York: AIAA.Google Scholar
Vaiana, G., Davis, J., Giacconi, R., Krieger, A., Silk, J., Timothy, A., and Zombeck, M.: 1973, Astrophys. J. 185, L47.Google Scholar
Vaiana, G., Krieger, A., Timothy, A., and Zombeck, M.: 1976, Astrophys. Space Sci. 39, 75.Google Scholar
Vaiana, G., Reidy, W., Zehnpfennig, T. and Van Speybroek, L.: 1968, Science 161, 564.Google Scholar
Vaiana, G., and Rosner, R.: 1978, Ann. Rev. Astron. Astrophys. 16, 393.Google Scholar
Velusamy, T. and Kundu, M.: 1980 (this volume), pp. 105.Google Scholar
Vorpahl, J., Tandberg-Hanssen, E. and Smith, J. Jr.: 1977, Astrophys. J. 212, 550.Google Scholar
Webb, D. and Zirin, J.: 1979, Bull. Am. Astron. Soc. 11, 410 (abstract).Google Scholar
White, O.: 1976, in I.A.U. Colloq. No. 36; Nice, France.Google Scholar
Withbroe, G.: 1976, in I.A.U. Colloq. No. 36; Nice, France.Google Scholar
Withbroe, G.: 1977, Proc. 1977 November 7–10, OSO-8 Workshop, pp. 127.Google Scholar
Withbroe, G. and Noyes, R.: 1977, Ann. Rev. Astron. Astrophys. 15, 363387.Google Scholar
Zheleznyakov, V.: 1962, Astron. Zh. 39, 5 (English translation in Sov. Astron. AJ 6, 3).Google Scholar