Abstract
The solar soft X-ray (XUV) radiation is important for upper atmosphere studies as it is one of the primary energy inputs and is highly variable. The XUV Photometer System (XPS) aboard the Solar Radiation and Climate Experiment (SORCE) has been measuring the solar XUV irradiance since March 2003 with a time cadence of 10 s and with about 70% duty cycle. The XPS measurements are between 0.1 and 34 nm and additionally the bright hydrogen emission at 121.6 nm. The XUV radiation varies by a factor of ∼2 with a period of ∼27 days that is due to the modulation of the active regions on the rotating Sun. The SORCE mission has observed over 20 solar rotations during the declining phase of solar cycle 23. The solar XUV irradiance also varies by more than a factor of 10 during the large X-class flares observed during the May–June 2003, October–November 2003, and July 2004 solar storm periods. There were 7 large X-class flares during the May–June 2003 storm period, 11 X-class flares during the October–November 2003 storm period, and 6 X-class flares during the July 2004 storm period. The X28 flare on 4 November 2003 is the largest flare since GOES began its solar X-ray measurements in 1976. The XUV variations during the X-class flares are as large as the expected solar cycle variations.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Brekke, P., Rottman, G. J., Fontenla, J., and Judge, P. G.: 1996, Astrophys. J. 468, 418.
Donnelly, R. F.: 1976, J. Geophys. Res. 81, 4745.
Donnelly, R. F. and Puga, L. C.: 1990, Solar Phys. 130, 369.
Garcia, H.: 2000, Astrophys. J. Suppl. 127, 189.
Kopp, R. A. and Pneuman, G. W.: 1976, Solar Phys. 50, 85.
Meier, R. R., Warren, H. P., Nicholas, A. C., Bishop, J., Huba, J. D., Drob, D. P., Lean, J., Picone, J. M., Mariska, J. T., Joyce, G., Judge, D. L., Thonnard, S. E., Dymond, K. F., and Budzien, S. A.: 2002, Geophys. Res. Lett. 29(10), doi: 10.1029/ 2001GL013956.
Neupert, W. M.: 1968, Astrophys. J. 153, L59.
Woods, T. N. and Rottman, G. J.: 2002, in M. Mendillo, A. Nagy, and J. Hunter Waite (eds.), Comparative Aeronomy in the Solar System, J. Geophys. Monograph Series, Washington, DC, pp. 221–234.
Woods, T. N., Rottman, G., and Vest, R.: 2005, Solar Phys., this volume.
Woods, T. N., Tobiska, W. K., Rottman, G. J., and Worden, J. R.: 2000, J. Geophys. Res. 105, 27195.
Woods, T. N., Bailey, S. M., Peterson, W. K., Warren, H. P., Solomon, S. C., Eparvier, F. G., Garcia, H., Carlson, C. W., and McFadden, J. P.: 2003, Space Weather 1(1), doi:10.1029/2003SW000010, 1001.
Woods, T. N., Acton, L. W., Bailey, S., Eparvier, F., Garcia, H., Judge, D., Lean, J., McMullin, D., Schmidtke, G., Solomon, S. C., Tobiska, W. K., and Warren, H. P.: 2004a, Solar Variability and Its Effect on Climate, Geophys. Monograph Series 141, Washington, DC, p. 127.
Woods, T. N., Eparvier, F. G., Fontenla, J., Harder, J., Kopp, G., McClintock, W. E., Rottman, G., Smiley, B., and Snow, M.: 2004b, Geophys. Res. Lett. L10802, doi: 10.1029/ 2004GL019571.
Worden, J. R., White, O. R., and Woods, T. N.: 1998, Astrophys. J. 496, 998.
Worden, J., Woods, T. N., Neupert, W. M., and Delaboundiniere, J. P.: 1999, Astrophys. J. 511, 965.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2005 Springer
About this chapter
Cite this chapter
Woods, T.N., Rottman, G. (2005). XUV Photometer System (XPS): Solar Variations During the SORCE Mission. In: Rottman, G., Woods, T., George, V. (eds) The Solar Radiation and Climate Experiment (SORCE). Springer, New York, NY. https://doi.org/10.1007/0-387-37625-9_17
Download citation
DOI: https://doi.org/10.1007/0-387-37625-9_17
Received:
Accepted:
Publisher Name: Springer, New York, NY
Print ISBN: 978-0-387-30242-3
Online ISBN: 978-0-387-37625-7
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)