We present the first weak lensing calibration of \mu _ { \star } , a new galaxy cluster mass proxy corresponding to the total stellar mass of red and blue members , in two cluster samples selected from the SDSS Stripe 82 data : 230 redMaPPer clusters at redshift 0.1 \leq z < 0.33 and 136 Voronoi Tessellation ( VT ) clusters at 0.1 \leq z < 0.6 .
We use the CS82 shear catalogue and stack the clusters in \mu _ { \star } bins to measure a mass-observable power law relation .
For redMaPPer clusters we obtain M _ { 0 } = ( 1.77 \pm 0.36 ) \times 10 ^ { 14 } h ^ { -1 } M _ { \odot } , \alpha = 1.74 \pm 0.62 .
For VT clusters , we find M _ { 0 } = ( 4.31 \pm 0.89 ) \times 10 ^ { 14 } h ^ { -1 } M _ { \odot } , \alpha = 0.59 \pm 0.54 and M _ { 0 } = ( 3.67 \pm 0.56 ) \times 10 ^ { 14 } h ^ { -1 } M _ { \odot } , \alpha = 0.68 \pm 0.49 for a low and a high redshift bin , respectively .
Our results are consistent , internally and with the literature , indicating that our method can be applied to any cluster-finding algorithm .
In particular , we recommend that \mu _ { \star } be used as the mass proxy for VT clusters .
Catalogs including \mu _ { \star } measurements will enable its use in studies of galaxy evolution in clusters and cluster cosmology .