We present extensive multi-color imaging and low resolution VIMOS Integral Field Unit ( IFU ) spectroscopic observations of the X-ray luminous cluster Abell 2667 ( z = 0.233 ) .
An extremely bright giant gravitational arc ( z = 1.0334 \pm 0.0003 ) is easily identified as part of a triple image system and other fainter multiple images are also revealed by the Hubble Space Telescope Wide Field Planetary Camera-2 images .
The VIMOS-IFU observations cover a field of view of 54 ^ { \prime \prime } \times 54 ^ { \prime \prime } and enable us to determine the redshift of all galaxies down to V _ { 606 } = 22.5 .
Furthermore , redshifts could be identified for some sources down to V _ { 606 } = 23.2 .
In particular we identify 21 cluster members in the cluster inner region , from which we derive a velocity dispersion of \sigma = 960 _ { -120 } ^ { +190 } km s ^ { -1 } , corresponding to a total mass of 7.1 \pm 1.8 10 ^ { 13 } h _ { 70 } ^ { -1 } M _ { \odot } within a 110 h _ { 70 } ^ { -1 } kpc ( 30 arcsec ) radius .
Using the multiple images constraints and priors on the mass distribution of cluster galaxy halos we construct a detailed lensing mass model leading to a total mass of 2.9 \pm 0.1 \times 10 ^ { 13 } h _ { 70 } ^ { -1 } M _ { \odot } within the Einstein radius ( 16 arcsec ) .
The lensing mass and dynamical mass are in good agreement although the dynamical one is much less accurate .
Within a 110 h _ { 70 } ^ { -1 } kpc radius , we find a rest-frame K-band M/L ratio of 61 \pm 5 h _ { 70 } M _ { \odot } /L _ { \odot } .
Comparing these measurements with published X-ray analysis , is however less conclusive .
Although the X-ray temperature matches the dynamical and lensing estimates , the published NFW mass model derived from the X-ray measurement with its small concentration of c \sim 3 can not account for the large Einstein radius observed in this cluster .
A larger concentration of \sim 6 would however match the strong lensing measurements .
These results are likely reflecting the complex structure of the cluster mass distribution , underlying the importance of panchromatic studies from small to large scale in order to better understand cluster physics .