Solar Physics

, Volume 286, Issue 1, pp 221–239

Sun-as-a-Star Observation of Flares in Lyman α by the PROBA2/LYRA Radiometer

PROBA2 – FIRST TWO YEARS OF SOLAR OBSERVATION

Abstract

There are very few reports of flare signatures in the solar irradiance at H i Lyman α at 121.5 nm, i.e. the strongest line of the solar spectrum. The LYRA radiometer onboard PROBA2 has observed several flares for which unambiguous signatures have been found in its Lyman-α channel. Here we present a brief overview of these observations followed by a detailed study of one of them: the M2 flare that occurred on 8 February 2010. For this flare, the flux in the LYRA Lyman-α channel increased by 0.6 %, which represents about twice the energy radiated in the GOES soft X-ray channel and is comparable with the energy radiated in the He ii line at 30.4 nm. The Lyman-α emission represents only a minor part of the total radiated energy of this flare, for which a white-light continuum was detected. Additionally, we found that the Lyman-α flare profile follows the gradual phase but peaks before other wavelengths. This M2 flare was very localized and had a very brief impulsive phase, but more statistics are needed to determine if these factors influence the presence of a Lyman-α flare signal strong enough to appear in the solar irradiance.

References

  1. Berghmans, D., Hochedez, J.F., Defise, J.M., Lecat, J.H., Nicula, B., Slemzin, V., Lawrence, G., Katsyiannis, A.C., van der Linden, R., Zhukov, A., Clette, F., Rochus, P., Mazy, E., Thibert, T., Nicolosi, P., Pelizzo, M.-G., Schühle, U.: 2006, SWAP onboard PROBA 2, a new EUV imager for solar monitoring. Adv. Space Res. 38, 1807 – 1811. doi:10.1016/j.asr.2005.03.070. ADSCrossRefGoogle Scholar
  2. Brekke, P., Rottman, G.J., Fontenla, J., Judge, P.G.: 1996, The ultraviolet spectrum of a 3B class flare observed with SOLSTICE. Astrophys. J. 468, 418 – 432. ADS:1996ApJ...468..418B. ADSCrossRefGoogle Scholar
  3. Brueckner, G.E., Edlow, K.L., Floyd, L.E. IV, Lean, J.L., Vanhoosier, M.E.: 1993, The Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) experiment on board the Upper Atmosphere Research Satellite (UARS). J. Geophys. Res. 981, 10695. ADS:1993JGR....9810695B. ADSCrossRefGoogle Scholar
  4. Canfield, R.C., van Hoosier, M.E.: 1980, Observed L-alpha profiles for two solar flares – 14:12 UT 15 June, 1973 and 23:16 UT 21 January, 1974. Solar Phys. 67, 339 – 350. ADS:1980SoPh...67..339C. doi:10.1007/BF00149811. ADSCrossRefGoogle Scholar
  5. Dominique, M., Hochedez, J.-F., Schmutz, W., Dammasch, I.E., Shapiro, A.I., Kretzschmar, M., benmoussa, A., Gillotay, D., Stockman, Y.: 2012, The LYRA instrument on-board PROBA2: description and in-flight performances. Solar Phys. submitted. Google Scholar
  6. Fletcher, L., Hudson, H.S.: 2008, Impulsive phase flare energy transport by large-scale Alfvén waves and the electron acceleration problem. Astrophys. J. 675, 1645 – 1655. doi:10.1086/527044. ADSCrossRefGoogle Scholar
  7. Fletcher, L., Hannah, I.G., Hudson, H.S., Metcalf, T.R.: 2007, A trace white light and RHESSI hard X-ray study of flare energetics. Astrophys. J. 656, 1187 – 1196. ADS:2007ApJ...656.1187F. ADSCrossRefGoogle Scholar
  8. Fröhlich, C., Crommelynck, D.A., Wehrli, C., Anklin, M., Dewitte, S., Fichot, A., Finsterle, W., Jiménez, A., Chevalier, A., Roth, H.: 1997, In-flight performance of the Virgo solar irradiance instruments on SOHO. Solar Phys. 175, 267 – 286. ADS:1997SoPh..175..267F. doi:10.1023/A:1004929108864. ADSCrossRefGoogle Scholar
  9. Handy, B.N., Acton, L.W., Kankelborg, C.C., Wolfson, C.J., Akin, D.J., Bruner, M.E., Caravalho, R., Catura, R.C., Chevalier, R., Duncan, D.W., Edwards, C.G., Feinstein, C.N., Freeland, S.L., Friedlaender, F.M., Hoffmann, C.H., Hurlburt, N.E., Jurcevich, B.K., Katz, N.L., Kelly, G.A., Lemen, J.R., Levay, M., Lindgren, R.W., Mathur, D.P., Meyer, S.B., Morrison, S.J., Morrison, M.D., Nightingale, R.W., Pope, T.P., Rehse, R.A., Schrijver, C.J., Shine, R.A., Shing, L., Strong, K.T., Tarbell, T.D., Title, A.M., Torgerson, D.D., Golub, L., Bookbinder, J.A., Caldwell, D., Cheimets, P.N., Davis, W.N., Deluca, E.E., McMullen, R.A., Warren, H.P., Amato, D., Fisher, R., Maldonado, H., Parkinson, C.: 1999, The Transition Region and Coronal Explorer. Solar Phys. 187, 229 – 260. ADS:1999SoPh..187..229H. doi:10.1023/A:1005166902804. ADSCrossRefGoogle Scholar
  10. Hochedez, J.-F., Schmutz, W., Stockman, Y., Schühle, U., Benmoussa, A., Koller, S., Haenen, K., Berghmans, D., Defise, J.-M., Halain, J.-P., Theissen, A., Delouille, V., Slemzin, V., Gillotay, D., Fussen, D., Dominique, M., Vanhellemont, F., McMullin, D., Kretzschmar, M., Mitrofanov, A., Nicula, B., Wauters, L., Roth, H., Rozanov, E., Rüedi, I., Wehrli, C., Soltani, A., Amano, H., van der Linden, R., Zhukov, A., Clette, F., Koizumi, S., Mortet, V., Remes, Z., Petersen, R., Nesládek, M., D’Olieslaeger, M., Roggen, J., Rochus, P.: 2006, Lyra, a solar UV radiometer on PROBA2. Adv. Space Res. 37, 303 – 312. ADS:2006AdSpR..37..303H. ADSCrossRefGoogle Scholar
  11. Hudson, H.S., Wolfson, C.J., Metcalf, T.R.: 2006, White-light flares: A TRACE/RHESSI overview. Solar Phys. 234, 79 – 93. ADS:2006SoPh..234...79H. doi:10.1007/s11207-006-0056-y. ADSCrossRefGoogle Scholar
  12. Johnson, H., Raymond, J.C., Murphy, N.A., Giordano, S., Ko, Y.-K., Ciaravella, A., Suleiman, R.: 2011, Transition region emission from solar flares during the impulsive phase. Astrophys. J. 735, 70. ADS:2011ApJ...735...70J. ADSCrossRefGoogle Scholar
  13. Kaufmann, P., Marcon, R., de Castro, C.G.G., White, S.M., Raulin, J.-P., Correia, E., Fernandes, L.O., de Souza, R.V., Godoy, R., Marun, A., Pereyra, P.: 2011, Sub-THz and H α activity during the preflare and main phases of a GOES class M2 event. Astrophys. J. 742, 106. ADS:2011ApJ...742..106K. ADSCrossRefGoogle Scholar
  14. Kohl, J.L., Esser, R., Gardner, L.D., Habbal, S., Daigneau, P.S., Dennis, E.F., Nystrom, G.U., Panasyuk, A., Raymond, J.C., Smith, P.L., Strachan, L., van Ballegooijen, A.A., Noci, G., Fineschi, S., Romoli, M., Ciaravella, A., Modigliani, A., Huber, M.C.E., Antonucci, E., Benna, C., Giordano, S., Tondello, G., Nicolosi, P., Naletto, G., Pernechele, C., Spadaro, D., Poletto, G., Livi, S., von der Lühe, O., Geiss, J., Timothy, J.G., Gloeckler, G., Allegra, A., Basile, G., Brusa, R., Wood, B., Siegmund, O.H.W., Fowler, W., Fisher, R., Jhabvala, M.: 1995, The Ultraviolet Coronagraph spectrometer for the Solar and Heliospheric Observatory. Solar Phys. 162, 313 – 356. ADS:1995SoPh..162..313K. doi:10.1007/BF00733433. ADSCrossRefGoogle Scholar
  15. Kretzschmar, M.: 2011, The Sun as a star: observations of white-light flares. Astron. Astrophys. 530, A84. ADS:2011A%26A...530A..84K. ADSCrossRefGoogle Scholar
  16. Kretzschmar, M., Dudok de Wit, T., Schmutz, W., Mekaoui, S., Hochedez, J., Dewitte, S.: 2010, The effect of flares on total solar irradiance. Nat. Phys. 6, 690 – 692. ADS:2010NatPh...6..690K. CrossRefGoogle Scholar
  17. Lemaire, P., Choucq-Bruston, M., Vial, J.-C.: 1984, Simultaneous H and K Ca II, H and K Mg II, L-alpha and L-beta H I profiles of the April 15, 1978 solar flare observed with the OSO-8/L.P.S.P. experiment. Solar Phys. 90, 63 – 82. ADS:1984SoPh...90...63L. doi:10.1007/BF00153785. ADSCrossRefGoogle Scholar
  18. Lemaire, P., Gouttebroze, P., Vial, J., Curdt, W., Schühle, U., Wilhelm, K.: 2004, Flare observation of the Sun as a star by SUMER/SOHO in the hydrogen Lyman continuum. Astron. Astrophys. 418, 737 – 742. ADS:2004A%26A...418..737L. ADSCrossRefGoogle Scholar
  19. Machado, M.E.: 1978, Soft X-ray emission and chromospheric flares. Solar Phys. 60, 341 – 351. ADS:1978SoPh...60..341M. doi:10.1007/BF00156534. ADSCrossRefGoogle Scholar
  20. Rottman, G.J., Woods, T.N., Sparn, T.P.: 1993, Solar-stellar irradiance comparison experiment 1. I – instrument design and operation. J. Geophys. Res. 981, 10667. ADS:1993JGR....9810667R. ADSCrossRefGoogle Scholar
  21. Rubio da Costa, F., Fletcher, L., Labrosse, N., Zuccarello, F.: 2009, Observations of a solar flare and filament eruption in Lyman α and X-rays. Astron. Astrophys. 507, 1005 – 1014. ADS:2009A&A...507.1005R. ADSCrossRefGoogle Scholar
  22. Seaton, D.B., Berghmans, D., Nicula, B., Halain, J.-P., De Groof, A., Thibert, T., Bloomfield, D.S., Raftery, C.L., Gallagher, P.T., Auchère, F., Defise, J.-M., D’Huys, E., Lecat, J.-H., Mazy, E., Rochus, P., Rossi, L., Schühle, U., Slemzin, V., Yalim, M.S., Zender, J.: 2012, The SWAP EUV imaging telescope part I: instrument overview and pre-flight testing. Solar Phys. doi:10.1007/s11207-012-0114-6. Google Scholar
  23. Wilhelm, K., Curdt, W., Marsch, E., Schühle, U., Lemaire, P., Gabriel, A., Vial, J.-C., Grewing, M., Huber, M.C.E., Jordan, S.D., Poland, A.I., Thomas, R.J., Kühne, M., Timothy, J.G., Hassler, D.M., Siegmund, O.H.W.: 1995, SUMER – Solar Ultraviolet Measurements of Emitted Radiation. Solar Phys. 162, 189 – 231. ADS:1995SoPh..162..189W, doi:10.1007/BF00733430. ADSCrossRefGoogle Scholar
  24. Woods, T.N., Rottman, G.J., Ucker, G.J.: 1993, Solar-stellar irradiance comparison experiment 1. II – Instrument calibrations. J. Geophys. Res. 981, 10679. ADS:1993JGR....9810679W. ADSCrossRefGoogle Scholar
  25. Woods, T.N., Eparvier, F.G., Fontenla, J., Harder, J., Kopp, G., McClintock, W.E., Rottman, G., Smiley, B., Snow, M.: 2004, Solar irradiance variability during the October 2003 solar storm period. Geophys. Res. Lett. 31, 10802. ADS:2004GeoRL..3110802W. ADSCrossRefGoogle Scholar
  26. Woods, T.N., Hock, R., Eparvier, F., Jones, A.R., Chamberlin, P.C., Klimchuk, J.A., Didkovsky, L., Judge, D., Mariska, J., Warren, H., Schrijver, C.J., Webb, D.F., Bailey, S., Tobiska, W.K.: 2011, New solar extreme-ultraviolet irradiance observations during flares. Astrophys. J. 739, 59. ADS:2011ApJ...739...59W. ADSCrossRefGoogle Scholar
  27. Yamaoka, K., Endo, A., Enoto, T., Fukazawa, Y., Hara, R., Hanabata, Y., Hong, S., Kamae, T., Kira, C., Kodaka, N., Kokubun, M., Maeno, S., Makishima, K., Miyawaki, R., Morigami, K., Murakami, T., Nakagawa, Y.E., Nakazawa, K., Ohmori, N., Ohno, M., Onda, K., Sato, G., Sonoda, E., Sugita, S., Suzuki, M., Suzuki, M., Tajima, H., Takahashi, T., Takahashi, T., Tanaka, H., Tamagawa, T., Tashiro, M.S., Terada, Y., Uehara, T., Urata, Y., Yamauchi, M., Yoshida, A., Hurley, K., Pal’Shin, V., Sakamoto, T., Cummings, J.: 2009, Design and in-orbit performance of the Suzaku Wide-Band All-Sky Monitor. Publ. Astron. Soc. Japan 61, 35. ADS:2009PASJ...61S..35Y. Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • M. Kretzschmar
    • 1
    • 2
  • M. Dominique
    • 1
  • I. E. Dammasch
    • 1
  1. 1.Royal Observatory of Belgium/SIDCBrusselsBelgium
  2. 2.LPC2EUMR7328 CNRS/Université d’OrléansOrleansFrance

Personalised recommendations