  We present a catalog of 59 z=4.5 Lyman alpha emitting galaxies
spectroscopically confirmed in a campaign of Keck/DEIMOS follow-up observations
to candidates selected in the Large Area Lyman Alpha (LALA) narrow-band imaging
survey. We targeted 97 candidates for spectroscopic follow-up; by accounting
for the variety of conditions under which we performed spectroscopy, we
estimate a selection reliability of about 76%. Together with our previous
sample of Keck/LRIS confirmations, the 59 sources confirmed herein bring the
total catalog to 73 spectroscopically confirmed z=4.5 Lyman alpha emitting
galaxies in the 0.7 square degrees covered by the LALA imaging. As with the
Keck/LRIS sample, we find that a non-negligible fraction of the confirmed Lyman
alpha lines have rest-frame equivalent widths (w_{rest}) which exceed the
maximum predicted for normal stellar populations: 17% -- 31% (93% confidence)
of the detected galaxies show w_{rest} > 190 AA, and 12% -- 27% (90%
confidence) show w_{rest} > 240 AA. We construct a luminosity function of z=4.5
Lyman alpha emission lines for comparison to Lyman alpha luminosity functions
spanning 3.1 < z < 6.6. We find no significant evidence for Lyman alpha
luminosity function evolution from z ~ 3 to z ~ 6. This result supports the
conclusion that the intergalactic medium remains largely reionized from the
local universe out to z=6.5. It is somewhat at odds with the pronounced drop in
the cosmic star formation rate density recently measured between z~3 and z~6 in
continuum-selected Lyman-break galaxies, and therefore potentially sheds light
on the relationship between the two populations.
