Context : The presence of two stellar populations in the Milky Way bulge have been reported recently , based on observations of giant and dwarf stars in the inner an intermediate bulge .

Aims : We aim at studying the abundances and kinematics of stars in the outer Galactic bulge , thereby providing additional constraints on formation models of the bulge .

Methods : Spectra of 401 red giant stars in a field at ( l,b ) = ( 0 \degr, - 10 \degr ) were obtained with the FLAMES-GIRAFFE spectrograph at the VLT .
Stars of luminosities down to below the two bulge red clumps are included in the data set .
From these spectra we measure general metallicities , abundances of iron and the \alpha -elements , and radial velocities of the stars .
The abundances are derived from an interpolation and fitting procedure within a grid of COMARCS model atmospheres and spectra .
These measurements as well as photometric data are compared to simulations with the Besançon and TRILEGAL models of the Galaxy .

Results : We confirm the presence of two populations among our sample stars : i ) a metal-rich one at [ { M } / { H } ] \sim + 0.3 , comprising about 30 % of the sample , with low velocity dispersion and low \alpha -abundance , and ii ) a metal-poor population at [ { M } / { H } ] \sim - 0.6 with high velocity dispersion and high \alpha -abundance .
The metallicity difference between the two populations , a systematically and statistically robust figure , is { \Delta } [ { M } / { H } ] = 0.87 \pm 0.03 .
The metal-rich population could be connected to the Galactic bar .
We identify this population as the carrier of the double red clump feature .
We do not find a significant difference in metallicity or radial velocity between the two red clumps , a small difference in metallicity being probably due to a selection effect and contamination by the metal-poor population .
The velocity dispersion agrees well with predictions of the Besançon Galaxy model , but the metallicity of the “ thick bulge ” model component should be shifted to lower metallicity by 0.2 to 0.3 dex to well reproduce the observations .
We present evidence that the metallicity distribution function depends on the evolutionary state of the sample stars , suggesting that enhanced mass loss preferentially removes metal-rich stars .
We also confirm the decrease of \alpha -element over-abundance with increasing metallicity .

Conclusions : Our sample is consistent with the existence of two populations , one being a metal-rich bar , the second one being more like a metal-poor classical bulge with larger velocity dispersion .