(a) Mean intergalactic transmission for a source at redshift z = 3.5
(solid lines). The mean intergalactic transmission assuming no Lyman
Limit Systems lie along the line-of-sight is shown by the dashed
lines. (b) Mean intergalactic transmission for, from left to right,
sources at redshifts z = 2.5, 3.5 and 4.5. The heavy lines are the
estimates from Meiksin (2006). In both panels, the light lines are
earlier estimates from Madau (1995).