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photosynthetically active radiation
PAR
total photon exposure in the 400 nm to 700 nm waveband
Note 1 to entry: The photosynthetically active radiation is expressed in mole per square metre per second (mol·m−2·s−1) or mole per square metre per day (mol·m−2·d−1).
Note 2 to entry: This entry was numbered 17-943 and 17-859 in CIE S 017:2011.