Solar Physics

, Volume 258, Issue 1, pp 141–166 | Cite as

The Ulysses Catalog of Solar Hard X-Ray Flares

  • C. TranquilleEmail author
  • K. Hurley
  • H. S. Hudson
Open Access


Ulysses was launched in October 1990, and its Solar X-ray/Cosmic Gamma-Ray Burst Experiment (GRB) has provided more than 13 years of uninterrupted observations of solar X-ray flare activity. Due to the large variation of the relative solar latitude and longitude of the spacecraft orbit with respect to the Earth, the perspective of the GRB instrument often differed significantly from that of X-ray instruments on Earth-orbiting satellites. During extended periods the GRB experiment made direct observations of flares on the hidden face of the Sun, providing a unique record of events not visible to other instruments. The small detector area of GRB and its optimization for very high counting rates minimized the effects of pulse pile-up. We interpret the spectra, time histories, and occurrence distribution patterns of GRB data in terms of “thermal feed-through”, the confusion of thermal soft X-rays and non-thermal hard X-rays. This effect is a systematic problem for scintillation-counter spectrometers observing the solar hard X-ray spectrum. This paper provides a definitive catalog of the Ulysses X-ray flare observations and discusses various features of this unique database. For the equivalent GOES range X2 – X25, we find a power-law fit for the (differential) occurrence frequency at >25 keV with slope −1.61±0.04, with no evidence for a downturn at the highest event magnitudes (for the relatively small sample of such events available in this study). If the nine most intense events are excluded because of concerns about the effects of pulse pile-up, the slope steepens to −1.75±0.08.


Count Rate Solar Phys Solar Limb Entrance Window Energetic Event 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. Battaglia, M., Grigis, P.C., Benz, A.O.: 2005, Astron. Astrophys. 439, 737. CrossRefADSGoogle Scholar
  2. Brodrick, D., Tingay, S., Wieringa, M.: 2005, J. Geophys. Res. (Space Phys.) 110, 9. CrossRefGoogle Scholar
  3. Cliver, E.W., Dennis, B.R., Kiplinger, A.L., Kane, S.R., Neidig, D.F., Sheeley, N.R. Jr., Koomen, M.J.: 1986, Astrophys. J. 305, 920. CrossRefADSGoogle Scholar
  4. Crawford, D.F., Jauncey, D.L., Murdoch, H.S.: 1970, Astrophys. J. 162, 405. CrossRefADSMathSciNetGoogle Scholar
  5. Crosby, N., Aschwanden, M. Dennis, B.R.: 1993, Solar Phys. 143, 275. CrossRefADSGoogle Scholar
  6. Crosby, N., Vilmer, N., Lund, N., Sunyaev, R.: 1998, Astron. Astrophys. 334, 299. ADSGoogle Scholar
  7. Datlowe, D.W.: 1975, Space Sci. Inst. 1, 389. Google Scholar
  8. Dennis, B.R.: 1985, Solar Phys. 100, 465. CrossRefADSGoogle Scholar
  9. Dennis, B.R.: 1988, Solar Phys. 118, 49. CrossRefADSMathSciNetGoogle Scholar
  10. Dennis, B.R., Zarro, D.M.: 1993, Solar Phys. 146, 177. CrossRefADSGoogle Scholar
  11. Feldman, U.: 1996, Phys. Plasmas, 3, 3203. CrossRefADSGoogle Scholar
  12. Frost, K.J., Dennis, B.R.: 1971, Astrophys. J. 165, 655. CrossRefADSGoogle Scholar
  13. Garcia, H.A.: 1990, Solar Phys. 127, 185. CrossRefADSGoogle Scholar
  14. Garcia, H.A., McIntosh, P.S.: 1992, Solar Phys. 141, 109. CrossRefADSGoogle Scholar
  15. Holman, G.D., Sui, L., Sui, L., Schwartz, R.A., Emslie, A.G.: 2003, Astrophys. J. 595, L97. CrossRefADSGoogle Scholar
  16. Hudson, H.S.: 1978, Astrophys. J. 224, 235. CrossRefADSGoogle Scholar
  17. Hudson, H.S.: 1991, Solar Phys. 133, 357. CrossRefADSGoogle Scholar
  18. Hudson, H., Ryan, J.: 1995, Annu. Rev. Astron. Astrophys. 33, 239. CrossRefADSGoogle Scholar
  19. Hurley K.: 1986, In: Marsden, R.G. (ed.) The Sun and the Heliosphere in Three Dimensions, Reidel, Dordrecht, 73. Google Scholar
  20. Hurley, K., Sommer, M., Atteia, J.L., Boer, M., Cline, T., Cotin, F., Henoux, J.C., Kane, S., Lowes, P., Niel, M.: 1992, Astron. Astrophys. 92, 401. ADSGoogle Scholar
  21. Kane, S.R., Hudson, H.S.: 1970, Solar Phys. 14, 414. CrossRefADSGoogle Scholar
  22. Kane, S.R., McTiernan, J.M., Hurley, K.: 2005, Astron. Astrophys. 433, 1133. CrossRefADSGoogle Scholar
  23. Kane S.R., Crannell C.J., Datlowe D., Feldman U., Gabriel A., Hudson H.S., Kundu M.R., Maetzler C., Neidig D., Petrosian V.: 1980, In: Sturrock, P.A. (ed.) Solar Flares: A Monograph from Skylab Solar Workshop II., Colorado Assoc. Univ. Press, Boulder, 187. Google Scholar
  24. Kane, S.R., Hurley, K., McTiernan, J.M., Sommer, M., Boer, M., Niel, M.: 1995, Astrophys. J. 446, L47. CrossRefADSGoogle Scholar
  25. Kane, S.R., Hurley, K., McTiernan, J.M., Boer, M., Niel, M., Kosugi, T., Yoshimori, M.: 1998, Astrophys. J. 500, 1003. CrossRefADSGoogle Scholar
  26. Kiplinger A.L., Garcia H.A.: 2004, Bull. Am. Astron. Soc. 36, 739. ADSGoogle Scholar
  27. Kucera, T.A., Dennis, B.R., Schwartz, R.A., Shaw, D.: 1997, Astrophys. J. 475, 338. CrossRefADSGoogle Scholar
  28. Lin, R.P., Schwartz, R.A., Pelling, R.M., Hurley, K.C.: 1981, Astrophys. J. 251, L109. CrossRefADSGoogle Scholar
  29. Lin, R.P., Dennis, B.R., Hurford, G.J., Smith, D.M., Zehnder, A., Harvey, P.R., et al.: 2002, Solar Phys. 210, 3. CrossRefADSGoogle Scholar
  30. Lingenfelter R.E., Hudson H.S.: 1980, In: Pepin, R.O., Eddy, J.A., Merrill, R.B. (eds.) The Ancient Sun: Fossil Record in the Earth, Moon and Meteorites, Pergamon Press, Elmsford, 69. Google Scholar
  31. Nakajima, H., Dennis, B.R., Hoyng, P., Nelson, G., Kosugi, T., Kai, K.: 1985, Astrophys. J. 288, 806. CrossRefADSGoogle Scholar
  32. Neupert, W.M.: 1968, Astrophys. J. 153, L59. CrossRefADSGoogle Scholar
  33. Orwig, L.E., Frost, K.J., Dennis, B.R.: 1980, Solar Phys. 65, 25. CrossRefADSGoogle Scholar
  34. Osten, R.A., Drake, S., Tueller, J., Cummings, J., Perri, M., Moretti, A., Covino, S.: 2007, Astrophys. J. 654, 1052. CrossRefADSGoogle Scholar
  35. Reedy R.C.: 1996, In: Balasubramaniam, K.S., Keil, S.L., Smartt, R.N. (eds.) Solar Drivers of the Interplanetary and Terrestrial Disturbances CS-95, Astron. Soc. Pac., San Francisco, 429. Google Scholar
  36. Reedy R.C., Marti K.: 1991, In: Sonett, C.P., Giampapa, M.S., Matthews, M.S. (eds.) The Sun in Time, Univ. Arizona Press, Tucson, 260. Google Scholar
  37. Smith H.J., Smith E.V.P.: 1963, Solar Flares, Macmillan, New York. Google Scholar
  38. Thomson, N.R., Rodger, C.J., Dowden, R.L.: 2004, Geophys. Res. Lett. 31, L06803. CrossRefGoogle Scholar
  39. Tomczak, M.: 2001, Astron. Astrophys. 366, 294. CrossRefADSGoogle Scholar
  40. Veronig, A., Temmer, M., Hanslmeier, A., Otruba, W., Messerotti, M.: 2002, Astron. Astrophys. 382, 1070. CrossRefADSGoogle Scholar

Copyright information

© The Author(s) 2009

Authors and Affiliations

  1. 1.Research and Scientific Support DepartmentESA/ESTECNoordwijkThe Netherlands
  2. 2.Space Sciences LaboratoryUC BerkeleyBerkeleyUSA

Personalised recommendations