Calculation of Cross Section of Radiative Halo—Neutron Capture by ^12C at Stellar Energy with the Asymptotic Normalization Coefficient Method

The cross section of the direct neutron capture reaction 12C(n,γ)^13C(1/2^ ) is calculated with the asymptotic normalization coefficient method.The result is in good agreement with a recent experiment at low energy,An enormous enhancement of cross section is found for this direct neutron capture in which a p-wave neutron is captured into an 2s1/2 orbit with neutron halo.The possible effect of the neutron halo structure presented in this reaction on the s-precess in astrophysics is discussed in general.     

The c—Axis Infrared Conductivity of a dx^2—y^2— Wave Superconductor with the Hopping Assisted by the Spin Fluctuations

A theory of the c-axis infrared conductivity of a dx^2-y^2- wave superconductor due to the competition between the interlayer direct hopping and the hopping assisted by the spin fluctuations has been developed.The prediction of our theory captures the main feature of the experiment.Thus we argue that the anomalous behavior of the c-axis infrared conductivity of the underdoped cuprates in superconducting state may be properly understood within the theory.