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
Article
  • 34 Downloads

Abstract

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.

Keywords

Burning Explosive Neon Nuclear Reaction Density Condition 

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Copyright information

© D. Reidel Publishing Company 1985

Authors and Affiliations

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

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