Neutrino energy loss by electron capture on strongly screened iron group nuclei

The influences on the neutrino energy loss rates in iron group nuclei at the same density are investigated in the presence of strong electron screening and in the absence of electron screening. The results show that at a temperature of 15 × 10⁹ K, the neutrino energy loss rates which come from the electron capture process for most iron group nuclei decrease no more than 2 orders of magnitude but for the others (such as ^{53,55,56,57,58,59,60} Co, ^56,59Ni) they can decrease about 3 orders of magnitude due to strong electron screening (SES), whereas, at a temperature of 10⁹K the neutrino energy loss rates of the most iron group nuclei can be diminished greatly due to the SES. For example, ⁶¹Fe, ⁶⁰Fe, and ⁶²Ni the neutrino energy loss rates decrease about 4, 15 and 16 orders of magnitude and for ⁵⁷Cr, ⁵⁸Cr, and ⁶⁰Cr decrease about 18, 12, and 10 orders of magnitude respectively. According to our calculations the neutrino energy loss rates of nuclei ⁵⁸Mn, ⁵⁹Mn, ⁶⁰Mn, and ⁶²Mn may decrease about 13 orders of magnitude at a temperature of 10⁹ K due to the SES.