  $^{83m}Kr$ and $^{22}Na$ have been used in calibrating a liquid argon (LAr)
detector.$^{83m}Kr$ atoms are produced through the decay of $^{83}Rb$ and
introduced into the LAr detector through the circulating purification system.
The light yield reaches 7.26$\pm$0.02 photonelectrons/keV for 41.5keV from
$^{83m}Kr$ and 7.66$\pm$0.01 photonelectrons/keV for the 511keV from $^{22}Na$,
as a comparison. The light yield varies with the drift electric field from 50
to 200V/cm have been also reported. After stopping fill, the decay rate of
$^{83m}Kr$ with a fitted half-life of 1.83$\pm$0.11 h, which is consistent with
the reported value of 1.83$\pm$0.02 h.
