Abstract
The measurements of the hard X-ray spectrum of Sco X-1 in the energy interval 20–150 keV in three balloon flights from Hyderabad, India are reported. These results show conclusively that the spectrum of Sco X-1 is very flat in the energy interval 40–150 keV and the measured fluxes beyond 60 keV are several orders of magnitude higher than those expected on the basis of an extrapolation of bremsstrahlung spectrum from a thin hot plasma at a temperature corresponding tokT=5 keV, which is applicable for Sco X-1 for energies <40 keV. The results are compared with those of other investigators of hard X-rays from Sco X-1, and the implication of the results is briefly discussed.
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Agrawal, P. C., Biswas, S., Gokhale, G. S., Ivengar, V. S., Kunte, P. K., Manchanda, R. K., and Sreekantan, B. V.: 1969a, in L. Gratton (ed.), ‘Non Solar X-Ray and γ-Ray Astronomy’,IAU Symp..37, Reidel, Dordrecht.
Agrawal, P. C., Biswas, S., Gokhale, G. S., Iyengar, V. S., Kunte, P. K., Manchanda, R. K., and Sreekantan, B. V.: 1969b,Nature 224, 51.
Agrawal, P. C., Biswas, S., Gokhale, G. S., Iyengar, V. S., Kunte, P. K., Manchanda, R. K., and Sreekantan, B. V.: 1970,Proc. XIth International Conf. on Cosmic Rays, Budapest, Aug.–Sept. 1969, Acta Physica Acad. Scien. Hung. 29, Suppl. 1, 277.
Burginyon, G. A., Grader, R. J., Hill, R. W., Hiltner, W. A., Mannery, E. J., Price, R. E., Rodriques, R., Seward, F. D., and Swift, C. D.: 1970, LRL Preprint, to appear inAstrophys. J..
Buselli, G., Clancy, M. C., Davison, P. J. N., Edwards, P. J., McCracken, K. G., and Thomas, R. M.: 1968,Nature 219, 1124.
Chodil, G., Jopson, R. C., Mark, H., Seward, F. D., and Swift, C. D.: 1965,Phys. Rev. Letters 15, 605.
Chodil, G., Mark, H., Rodriques, R., and Swift, C. D.: 1967,Astrophys. J. 150, 57.
Clark, G. W., Lewin, W. H. G., and Smith, W. B.: 1968,Astrophys. J. 151, 21.
Gorenstein, P., Giaconni, R., and Gursky, H.: 1967,Astrophys. J. Letters 150, L85.
Grader, R. J., Hill, R. W., Seward, F. D., and Toor, A.: 1966,Science 152, 1499.
Haymes, R. C. and Hardon, F. R., Jr.: 1970,Astrophys. J. 159, 1111.
Kitamura, T., Matsuoka, M., Miyamato, S., Oda, M., Ogawar, Y., Nakagawa, M., and Takagishi, K.: 1970,Space Res. 10, in press.
Lewin, W. H. G., Clark, G. W., and Smith, W. B.: 1967,Astrophys. J. Letters,150, L153.
Manchanda, R. K., Agrawal, P. C., Biswas, S., Gokhale, G. S., Iyengar, V. S., Kunte, P. K., and Sreekantan, B. V.: 1970, in press.
Overbeck, J. W. and Tananbaum, H. D.: 1968,Astrophys. J. 153, 899.
Peterson, L. E. and Jacobson, A. S.: 1966,Astrophys. J. 145, 62.
Peterson, L. E., Jacobson, A. S., Pelling, R. M., and Schwartz, D. A.: 1968,Can. J. Phys. 46, S437.
Riegler, R. and Ramaty, R.: 1969,Astrophys. Letters 4, 27.
Riegler, R., Boldt, E., and Serlemitsos, P.: 1970,Nature 226, 1041.
Rocchia, R., Rothenflug, R., Boclet, D., and Durochoux, Ph.: 1969,Astron. Astrophys. 1, 48.
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Agrawal, P.C., Biswas, S., Gokhale, G.S. et al. The flattening of the X-ray spectrum of sco X-1 at energies beyond 40 keV. Astrophys Space Sci 10, 500–507 (1971). https://doi.org/10.1007/BF00649692
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DOI: https://doi.org/10.1007/BF00649692