B. Davids, J. Jose
Published 2003-02-10Version 1
The 15O(alpha,gamma)19Ne reaction is one of two known routes for breakout from the hot CNO cycles into the rp process. Its astrophysical rate depends on the decay properties of excited states in 19Ne lying just above the 15O + alpha threshold. We have measured the alpha-decay branching ratios for these states using the p(21Ne,t)19Ne reaction at 43 MeV/u. Combining our branching ratio measurements with previous determinations of the radiative widths of these states, we calculate the astrophysical rate of 15O(alpha,gamma)19Ne. Using this reaction rate, we perform hydrodynamic calculations of nova outbursts and conclude that no significant breakout from the hot CNO cycles into the rp process occurs in classical novae via 15O(alpha,gamma)19Ne.
Comments: Contribution to proceedings of the 2003 Hirschegg Workshop on Nuclear Structure and Dynamics at the Limits
Excited states of $^{39}$Ca and their significance in nova nucleosynthesis
The astrophysical rate of 15O(alpha,gamma)19Ne via the (p,t) reaction in inverse kinematics
Alpha-decay branching ratios of near-threshold states in 19Ne and the astrophysical rate of 15O(alpha,gamma)19Ne
