darkhistory.physics.He_exc_eng

darkhistory.physics.He_exc_eng = {'10p1P': 24.452, '21p': 21.218022836660744, '21s': 20.6157749667322, '23p': 20.964115970937566, '23s': 19.819614683951094, '2p': 21.218022836660744, '2p1P': 21.218, '3p1P': 23.087, '4p1P': 23.742, '5p1P': 24.046, '6p1P': 24.211, '7p1P': 24.311, '8p1P': 24.375, '9p1P': 24.42}

HeI n=1 to n=2 excitation energies in eV, and n=1 to 3p through 10p