Context : We determine the Galactic potential in the solar neigbourhood from RAVE observations .
We select red clump stars for which accurate distances , radial velocities , and metallicities have been measured .
Combined with data from the 2MASS and UCAC catalogues , we build a sample of \sim 4600 red clump stars within a cylinder of 500 pc radius oriented in the direction of the South Galactic Pole , in the range of 200 pc to 2000 pc distances .
We deduce the vertical force and the total mass density distribution up to 2 kpc away from the Galactic plane by fitting a distribution function depending explicitly on three isolating integrals of the motion in a separable potential locally representing the Galactic one with four free parameters .
Because of the deep extension of our sample , we can determine nearly independently the dark matter mass density and the baryonic disc surface mass density .
We find ( i ) at 1 kpc K _ { z } / ( 2 \pi G ) = 68.5 \pm 1.0 M _ { \sun } pc ^ { -2 } , and ( ii ) at 2 kpc K _ { z } / ( 2 \pi G ) = 96.9 \pm 2.2 M _ { \sun } pc ^ { -2 } .
Assuming the solar Galactic radius at R _ { 0 } = 8.5 kpc , we deduce the local dark matter density \rho _ { DM } ( z = 0 ) = 0.0143 \pm 0.0011 M _ { \sun } pc ^ { -3 } = 0.542 \pm 0.042 { Gev cm ^ { -3 } } and the baryonic surface mass density \Sigma _ { bar } = 44.4 \pm 4.1 M _ { \sun } pc ^ { -2 } .
Our results are in agreement with previously published K _ { z } determinations up to 1 kpc , while the extension to 2 kpc shows some evidence for an unexpectedly large amount of dark matter .
A flattening of the dark halo of order 0.8 can produce such a high local density in combination with a circular velocity of 240 km s ^ { -1 } .
It could also be consistent with a spherical cored dark matter profile whose density does not drop sharply with radius .
Another explanation , allowing for a lower circular velocity , could be the presence of a secondary dark component , a very thick disc resulting either from the deposit of dark matter from the accretion of multiple small dwarf galaxies , or from the presence of an effective ’ phantom ’ thick disc in the context of effective galactic-scale modifications of gravity .

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