NTM

30 keV Neutron Capture Cross Sections


 

The Solar Spectrum

Where available, we have normalized the neutron capture rates of RATH to agree with the measured maxwellian averaged capture cross sections from Bao et al. 2000 (herefter MACS_x) at 30 keV.

We calculate an estimate of the neutron capture cross section at 30 keV (hereafter MACS_c) from the neutron capture rate given by our reaction rate fits using formula #41 of OAP-422 (Woosley, Fowler, Holmes & Zimmerman 1975, "Tables of Thermonuclear Reaction Rate Data for Intermediate Mass Nuclei", Calif. Institute of Technology, Kellogg Radiation Laboratory Preprint No. 422):

MACS_c = 6.90e-6*SQRT(an)*(0.48*rp3 + 0.52*rp4) (mb)

where a = mass number of the target, an = a/(a+1.), and rp3 and rp4 are the (n,g) reaction rate evaluated at T9=0.3 and T9=0.4 respectively.

We provide a table which lists for a given target nucleus (Z,A) the calculated capture cross section (MACS_c), the experimental maxwellian averaged cross section (MACS_x), and its quoted error (MACS_err). For those cases where MACS_c is outside MACS_x +- MACS_err, the difference between the calculated and experimental MACS is given in mb.

NO account is taken for the stellar enhancement factor (SEF), although our RATH (n,g) rates include this. For the calculated MACS that were outside the errors of the experimental MACS, we provide the stellar enhancement factor (SEF) from the Bao et al. 2000 paper. Multiplication of the MACS_x by SEF gives the calculated MACS_c to within a small error (less than the quoted error of the MACS_x).


[Calculated MACS vs. Experiment]
[Complete Table]

 


May 30, 2002. For information about this page, contact Rob Hoffman
UCRL-WEB-148486