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Description
A precise derivation of the evolution of the Tully-Fisher is crucial to understand the interplay between dark matter and baryonic matter in cosmological models, using 15 deployable integral field units of FLAMES/GIRAFFE at VLT, we have recovered the velocity fields of 35 galaxies at intermediate redshift (0.4<z<0.75). This facility is able to recover the velocity fields of almost all the emission line galaxies with I_AB_<=22.5 and W_0_(OII)>=15{AA}. In our sample, we find only 35% rotating disks. These rotating disks produce a Tully-Fisher relationship (stellar mass or MK versus Vmax which has apparently not evolved in slope, zero point and scatter since z=0.6). The only evolution found is a brightening of the B band luminosity of a third of the disks, possibly due to an enhancement of the star formation. The very large scatters found in previously reported Tully-Fisher relationships at moderate redshifts are caused by the numerous (65%) galaxies with perturbed or complex kinematics. Those galaxies include minor or major mergers, merger remnants and/or inflow/outflows and their kinematics can be easily misidentified by slit spectroscopy. Their presence suggests a strong evolution in the dynamical properties of galaxies during the last 7Gyr.
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