More on big-bang nucleosynthesis with nonzero lepton numbers

Abstract

The calculation of big-bang nucleosynthesis with nonzero lepton numbers is extended to atomic weights less than 12. The observed abundances of D and He-4 place only a lower limit on the present mean baryon density of the Universe: not less than 5 x 10 to the -31st g/cu cm for primordial D/H equals .000014 by number (assuming no astration), and not less than 3.5 x 10 to the -31st g/cu cm if the primordial abundance was twice as high, and half of it has been destroyed in stars. In the case of astration, primordial Li-7 can account at most for only about 25 percent of the observed abundance (15 percent for zero lepton numbers).