Low energy γ-ray spectrum of NGC4151

Abstract

Following the first detection of X-ray emission from the Seyfert galaxy NGC41511, later observations2–4 have demonstrated that the X-ray spectrum up to 100 keV may be described by a power law having a differential spectral index 1<α><1.6 with a turnover at low energies caused by photoelectric absorption. Recently the results of an observation of this galaxy in the energy range 25–190 keV (ref. 5) have shown it to have a very hard spectrum with α0.9. Here more detailed results of the original observation of NGC4151 (ref. 6) using the MISO telescope are presented.

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References

  1. 1

    Gursky, H., Kellogg, E. M., Leong, C., Tananbaum, H. & Giacconi, R. Astrophys. J. Lett. 165, L43 ( 1971).

  2. 2

    Baity, W. A., Jones, T. W., Wheaton, Wm. A. & Peterson, L. E. Astrophys. J. Lett. 199, L5 (1975).

  3. 3

    Ives, J. C., Sandford, P. W. & Penston, M. V. Astrophys. J. Lett. 207, L159 (1976).

  4. 4

    Paciesas, W. S., Mushotzky, R. F. & Pelling, R. M. Mon. Not. R. astr. Soc. 178, 23P (1977).

  5. 5

    Auriemma, G. et al. Astrophys. J. Lett. 221, L7 (1978).

  6. 6

    Di Cocco, G. et al. Nature 270, 319 (1977).

  7. 7

    Baker, R. E. et al. Nucl. Instrum. Meth. 158, 595 (1979).

  8. 8

    Dolan, J. F. Astrophys. Space Sci. 17, 472 (1972).

  9. 9

    Barr, P., White, N. E., Sanford, P. W. & Ives, J. C. Mon. Not. R. astr. Soc. 181, 43P (1977).

  10. 10

    Mushotzky, R. F., Holt, S. S. & Serlemitsos, P. J. Astrophys. J. Lett. 225, L115 (1978).

  11. 11

    Schonfelder, V. Nature 274, 344 (1978).

  12. 12

    Schonfelder, V. Announcement of Kyoto, 16th ICRC (1979).

  13. 13

    Bignami, G. F., Fichtel, C. E., Hartman, R. C. & Thompson, D. J. preprint (1979).

  14. 14

    Elvis, M. Mon. Not. R. astr. Soc. 177, 7P (1976).

  15. 15

    Meegan, C. A. & Haymes, R. C. preprint (1979).

  16. 16

    Zanrosso, E. M., Long, J. L., Zych, A. D., Gibbons, D. & White, R. S. Proc. 16th ICRC, Kyoto, og 4–3 (1979).

  17. 17

    Bergeron, J. & Salpeter, E. E. Astrophys. Lett. 9, 121 (1971).

  18. 18

    Bergeron, J. & Salpeter, E. E. Astr. Astrophys. 22, 385 (1973).

  19. 19

    Grindlay, J. E. Astrophys. J. 199, 49 (1975).

  20. 20

    Pinkau, K. Proc. 16th ICRC, Kyoto, og4–16 (1979).

  21. 21

    Fabian, A. C., Maccagni, D., Rees, M. J. & Stoeger, W. R. Nature 260, 683 (1976).

  22. 22

    Lightman, A. P., Giacconi, R. & Tananbaum, H. Astrophys. J. 224, 375 (1978).

  23. 23

    Maraschi, L., Perola, G. C., Reina, C. & Treves, A. Astrophys. J. (in the press).

  24. 24

    Pacini, F. & Salvati, M. Astrophys. J. Lett. 225, L99 (1978).

  25. 25

    Leiter, D. & Kafatos, M. Proc. La Jolla Institute, UCSD-Workshop on Particle Acceleration Mechanisms on Astrophysics (1979).

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Perotti, F., Ventura, A., Sechi, G. et al. Low energy γ-ray spectrum of NGC4151. Nature 282, 484–486 (1979). https://doi.org/10.1038/282484a0

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