We present the weak lensing analysis of 279 CODEX clusters using imaging data from 4200 \text { deg } ^ { 2 } of the DECam Legacy Survey ( DECaLS ) Data Release 3 .
The cluster sample results from a joint selection in X-ray , optical richness in the range 20 \leq \lambda < 110 , and redshift in the range 0.1 \leq z \leq 0.2 .
We model the cluster mass ( M _ { 200 c } ) and the richness relation with the expression \left \langle M _ { 200 c } | \lambda \right \rangle \propto M _ { 0 } ( \lambda / 40 ) ^ { F _ { % \lambda } } .
By measuring the CODEX cluster sample as an individual cluster , we obtain the best-fit values , M _ { 0 } = 3.24 ^ { +0.29 } _ { -0.27 } \times 10 ^ { 14 } \text { M } _ { \odot } , and F _ { \lambda } = 1.00 ^ { +0.22 } _ { -0.22 } for the richness scaling index , consistent with a power law relation .
Moreover , we separate the cluster sample into three richness groups ; \lambda = 20 - 30 , 30 - 50 and 50 - 110 , and measure the stacked excess surface mass density profile in each group .
The results show that both methods are consistent .
In addition , we find an excellent agreement between our weak lensing based scaling relation and the relation obtained with dynamical masses estimated from cluster member velocity dispersions measured by the SDSS-IV/SPIDERS team .
This suggests that the cluster dynamical equilibrium assumption involved in the dynamical mass estimates is statistically robust for a large sample of clusters .