Recent content by ak2478

Thoughts on number 1 for number 1: i know that number density = energy density/rest energy i have attempted to start with the black body spectrum equation i think my plan for this problem is to go from mass density --> to baryon density --> then to number density of hydrogen. I...

1. Hydrogen and Helium recombination Hydrogen recombines at a redshift of approximately z=1200, with recombination starting already at z=1600. a. What was the ratio of the number density of hydrogen-ionizing photons (i.e. photons with energies E > 13.6eV) to the number density of hydrogen...