  The NASA TESS mission will deliver hundreds of transiting exoplanet
candidates orbiting bright stars. The spectrometers SOPHIE at OHP and SPIRou at
CFHT will be ideal to obtain radial velocities of these candidates, confirm
their nature, and derive the planets' masses. These measurements will be
crucial to deliver the best targets for atmospheric characterization with JWST.
Here, we calculate the required observing time with SOPHIE, SPIRou, and JWST
for each of the TESS targets in order to prepare follow-up observations. To
infer their potential for JWST, we restrict the calculations to the case of
transmission spectroscopy with NIRISS. The radial velocity follow-up of the
giant planets ($R_p > 4 \rm \, R_E$) could be achieved with SOPHIE, with a
median observing time of 3.47 hours per target, and a total observing time of
305 hours that includes the 80% most favorable cases. Several small planets
($R_p < 4 \rm \, R_E$) could also be confirmed, but most of them would require
an unrealistic time investment. On the other hand, SPIRou is ideally suited to
the follow-up of the small planets, with a median observing time of 2.65 hours
per target, and a median observing time of 4.70 hours for the terrestrial
planets in the habitable zone ($R_p < 2 \rm \, R_E$, $S < 2 \rm \, S_E$). With
JWST, the 10% most favorable small planets (184 planets) have a median
observing time of 16.2 hours, and the 10% most favorable habitable zone
terrestrial planets (7 planets) have a median observing time of 59.7 hours.
Overall, this study will help define a follow-up strategy and prepare
observation programs with SOPHIE and SPIRou before the first planet candidates
are delivered by TESS.
