We report the outcome of the deep optical/infrared photometric survey of the central region ( 33 \times 33 arcmin or 0.9 pc ^ { 2 } ) of the \eta Chamaeleontis pre-main sequence star cluster .
The completeness limits of the photometry are I = 19.1 , J = 18.2 and H = 17.6 ; faint enough to reveal low mass members down to the brown dwarf and planet boundary of \approx 13 M _ { Jup } .
We found no such low mass members in this region .
Our result combined with a previous shallower ( I = 17 ) but larger area survey indicates that low mass objects ( 0.013 < M /M _ { \odot } < 0.075 ) either were not created in the \eta Cha cluster or were lost due to the early dynamical history of the cluster and ejected to outside the surveyed areas .