Context :

Aims : We attempt to detect starlight reflected from the hot Jupiter orbiting the main-sequence star \tau  Boo , in order to determine the albedo of the planetary atmosphere , the orbital inclination of the planetary system and the exact mass of the planetary companion .

Methods : We analyze high-precision , high-resolution spectra , collected over two half nights using UVES at the VLT/UT2 , by way of data synthesis .
We interpret our data using two different atmospheric models for hot Jupiters .

Results : Although a weak candidate signal appears near the most probable radial velocity amplitude , its statistical significance is insufficient for us to claim a detection .
However , this feature agrees very well with a completely independently obtained result by another research group , which searched for reflected light from \tau  Boo b .
As a consequence of the non-detection of reflected light , we place upper limits to the planet-to-star flux ratio at the 99.9 % significance level .
For the most probable orbital inclination around i = 46 ^ { \circ } , we can limit the relative reflected radiation to be less than \epsilon = 5.7 \times 10 ^ { -5 } for grey albedo .
This implies a geometric albedo smaller than 0.40 , assuming a planetary radius of 1.2 ~ { } { R _ { Jup } } .

Conclusions :