GJ1132 is a nearby red dwarf known to host a transiting Earth-size planet .
After its initial detection , we pursued an intense follow-up with the HARPS velocimeter .
We now confirm the detection of GJ1132b with radial velocities only .
We refined its orbital parameters and , in particular , its mass ( m _ { b } = 1.66 \pm 0.23 M _ { \oplus } ) , density ( \rho _ { b } = 6.3 \pm 1.3 g.cm ^ { -3 } ) and eccentricity ( e _ { b } < 0.22 ; 95 % ) .
We also detect at least one more planet in the system .
GJ1132c is a super-Earth with period P _ { c } = 8.93 \pm 0.01 days and minimum mass m _ { c } \sin i _ { c } = 2.64 \pm 0.44 ~ { } M _ { \oplus } .
Receiving about 1.9 times more flux than Earth in our solar system , its equilibrium temperature is that of a temperate planet ( T _ { eq } = 230 - 300 K for albedos A = 0.75 - 0.00 ) and places GJ1132c near the inner edge of the so-called habitable zone .
Despite an a priori favourable orientation for the system , Spitzer observations reject most transit configurations , leaving a posterior probability < 1 \% that GJ1132c transits .
GJ1132 ( d ) is a third signal with period P _ { d } = 177 \pm 5 days attributed to either a planet candidate with minimum mass m _ { d } \sin i _ { d } = 8.4 ^ { +1.7 } _ { -2.5 } ~ { } M _ { \oplus } or stellar activity .
Its Doppler signal is the most powerful in our HARPS time-series but appears on a time-scale where either the stellar rotation or a magnetic cycle are viable alternatives to the planet hypothesis .
On the one hand , the period is different than that measured for the stellar rotation ( \sim 125 days ) and a Bayesian statistical analysis we performed with a Markov Chain Monte Carlo and Gaussian Processes demonstrates the signal is better described by a keplerian function than by correlated noise .
On the other hand , periodograms of spectral indices sensitive to stellar activity shows power excess at similar periods than that of this third signal , and RV shifts induced by stellar activity can also match a keplerian function .
Eventually , we prefer to leave the status of ’ d ’ undecided .