Astrophysics and Space Science

, Volume 116, Issue 1, pp 97–106 | Cite as

Nuclear reactions on accreting neutron star surface

  • K. Duorah
  • H. L. Duorah


The production of X-rays and gamma-rays in bursts is believed to be due to the rapid burning of matter accreted onto a neutron star surface from its companion, most probably a giant star. The accreted matter consists mainly of hydrogen and helium and a very small amount of heavy elements. Due to the infall of matter, the temperature at the bottom layers is raised to a value of the order of 108 K. The neutron star surface density is>107 g cm−3. As hydrogen burning is a slow process under any temperature and density conditions, we consider the helium-burning reactions as the source of gamma-rays in the neutron star surface. Under high-density conditions the ordinary laboratory reaction rates should become modified. At high-density conditions, the strong screening effect due to the polarising cloud of electrons around the ions become important and enhances the reaction rates considerably. The helium-burning reactions are calculated under such conditions. The abundances of helium-burning products such as12C, 116O, and20Ne, etc., are computed. Under high-density and temperature conditions carbon is found to be more abundant than oxygen. Neon is completely absent in almost all the relevant physical conditions in which a strong screening effect is operative. It is suggested that explosive burning of accreted helium of 10−13M will account for the observed energy of gamm-ray burst.


Burning Explosive Neon Nuclear Reaction Density Condition 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Ayasli, S. and Joss, P. C.: 1982,Astrophys. J. 256, 637.Google Scholar
  2. Cameron, A. G. W.: 1957,Stellar Evolution, Nuclear Astrophysics, and Nucleogenesis, Chalk River Report CRL41.Google Scholar
  3. Duorah, H. L.: 1962,Prog. Theoret. Phys. 28, 585.Google Scholar
  4. Duorah, K., Duorah, H. L., and Zaman, A. E. K.: 1976:J. Assam Sci. Soc. 19, 31.Google Scholar
  5. Giacconi, R., Gursky, H., Kellog, E., Schreier, E. J. and Tananbaum, H.: 1971,Astrophys. J. 167, L67.Google Scholar
  6. Hansen, C. J. and Van Horn, H. M.: 1975,Astrophys. J. 191, 479.Google Scholar
  7. Hayakawa, S., Hayashi, C., Imoto, H., and Kikuchi, K.: 1956,Prog. Theoret. Phys. 16, 507.Google Scholar
  8. Hoyle, F. 1954,Astrophys. J. Suppl. 5, 121.Google Scholar
  9. Itoh, N., Totsuji, H., and Ichimaru, S.: 1977,Astrophys. J. 218, 324.Google Scholar
  10. Jancovici, J.: 1977,J. Stat. Phys. 17, 357.Google Scholar
  11. Joss, P. C.: 1977,Nature (London) 270, 310.Google Scholar
  12. Joss, P. C.: 1978,Astrophys. J. 225, L123.Google Scholar
  13. Joss, P. C. and Li, F. K.: 1980,Astrophys. J. 238, 287.Google Scholar
  14. Mazets, E. P., Golenetskii, S. V., Il'mskii, V. N., Aptekar, R. L., and Guruyan, Yu. A.: 1980,Nature (London) 282, 587.Google Scholar
  15. Nakagawa, K., Obmura, T., Takebe, H., and Obi, S.: 1956,Progr. Theoret. Phys. 16, 389.Google Scholar
  16. Ramaty, R. and Lingenfelter, R. E.: 1982,Ann. Rev. Nucl. Particle Sci. 32, 235.Google Scholar
  17. Ruderman, M.: 1977, Private communication.Google Scholar
  18. Salpeter, E. E.: 1954,Australian J. Phys. 7, 343.Google Scholar
  19. Salpeter, R. E. and Van Horn, H. M.: 1969,Astrophys. J. 155, 183.Google Scholar
  20. Taam, R. E.: 1980,Astrophys. J. 241, 358.Google Scholar
  21. Taam, R. E.: 1982,Astrophys. J. 258, 761.Google Scholar
  22. Taam, R. E. and Picklum, R. E.: 1979,Astrophys. J. 233, 327.Google Scholar
  23. Van Horn, H. M. and Hansen, C. J.: 1975,Astrophys. J. 191, 479.Google Scholar
  24. Woosley, S. E. and Taam, R. E.: 1976,Nature 263, 101.Google Scholar
  25. Zimmerman, B. A., Fowler, W. A., and Caughlan, G. R.: 1975, California Institute of Technology preprint, OAP-399.Google Scholar

Copyright information

© D. Reidel Publishing Company 1985

Authors and Affiliations

  • K. Duorah
    • 1
  • H. L. Duorah
    • 1
  1. 1.Department of PhysicsGauhati UniversityAssamIndia

Personalised recommendations