Abstract
The first results obtained with the Solar EUV Monitor (SEM), part of the Charge, Element, and Isotope Analysis System (CELIAS) instrument, aboard the SOlar and Heliospheric Observatory (SOHO) satellite are presented. The instrument monitors the full-disk absolute value of the solar Heii irradiance at 30.4 nm, and the full-disk absolute solar irradiance integrated between 0.1 nm and 77 nm. The SEM was first turned on December 15, 1995 and obtained ‘first light’ on December 16, 1995. At this time the SOHO spacecraft was close to the L-1 Lagrange point, 1.5 × 106 km from the Earth towards the Sun. The data obtained by the SEM during the first four and a half months of operation will be presented. Although the period of observation is near solar minimum, the SEM data reveal strong short-term solar irradiance variations in the broad-band, central image channel, which includes solar X-ray emissions.
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Acton, L.: 1996, private communication.
Barth, C. A., Tobiska, W. K., Siskind, D. E., and Cleary, D. D.: 1988, Geophys. Res. Letters 15, 92.
Canfield, L. R.: 1987, Appl. Optics 26, 3831.
Domingo, V.: 1989, in T. D. Guyenne (ed.), ESA SP-1104.
Freeman, F. F. and Jones, B.B.: 1970, Solar Phys. 15, 288.
Furst, M. L., Graves, R. M., Canfield, L. R., and Vest, R. E.: 1995, Rev. Sci. Instrum. 66, 2257.
Holzer, T. E.: 1977, Geophys. Space Phys. 15, 467.
Hovestadt, D., Hilchenbach, M., Bürgi, A., Klecker, B., Laeverenz, P., Scholer, M., Grunwaldt, H, Axford, W. I., Livi, S., Marsch, E., Wilken, B., Winterhoff, H. P., Ipavich, F. M., Bedini, P., Coplan, M. A., Galvin, A. B., Gloeckler, G., Bochsler, P., Balsiger, H., Fischer, J., Geiss, J., Kallenbach, R., Wurz, P., Reiche, K.-U., Gliem, F., Judge, D. L., Ogawa, H. S., Hsieh, K. C., Möbius, E., Lee, M. A., Managadze, G. G., Verigin, M. I., and Neugebauer, M.: 1995, Solar Phys. 162, 441.
Kreplin, R. W. and Horan, D. M.: 1992, in R. F. Donnelly (ed.), Proceedings of the Workshop on the Solar Electromagnetic Radiation Study for Solar Cycle 22, p. 405.
Lean, J.: 1990, J. Geophys. Res. 95(A8), 11933.
Möbius, E., Hovestadt, D., Klecker, B., Scholer, M., Gloeckler, G., and Ipavich, F. M.: 1985, Nature 318, 426.
Ogawa, H. S., McMullin, D. R., Judge, D. L., and Korde, R.: 1993, Optical Eng. 32, 3121.
Richards, P. G. and Torr, D. G.: 1984, J. Geophys. Res. 89, 5625.
Richards, P. G. and Torr, D. G.: 1988, J. Geophys. Res. 93, 4060.
Richards, P. G., Fennelly, J. A., and Torr, D. G.: 1994, J. Geophys. Res. 99, 8981.
Tobiska, W. K.: 1996, private communication.
Van Tassel, R. A., McMahon, W. J., and Héroux, L.: 1981, AFGL-TR–81–0111, Res. pap. 737.
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Judge, D.L., McMullin, D.R., Ogawa, H.S. et al. First Solar EUV Irradiances Obtained from SOHO by the Celias/Sem. Solar Physics 177, 161–173 (1998). https://doi.org/10.1023/A:1004929011427
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DOI: https://doi.org/10.1023/A:1004929011427