  Our understanding of magnetic fields in late-type stars is strongly driven by
what we know of the solar magnetic field. For this reason, it is crucial to
understand how typical the solar dynamo is. To do this we need to compare the
solar magnetic field with that of other stars as similar to the Sun as
possible, both in stellar parameters and age, hence activity. We present here
the detection of a magnetic field in three planet-hosting solar-like stars
having a mass, age, and activity level comparable to that of the Sun. We used
the HARPSpol spectropolarimeter to obtain high-resolution high-quality
circularly polarised spectra of HD 70642, HD 117207, and HD 154088, using the
Least-Squares Deconvolution technique to detect the magnetic field. From the
Stokes I spectra, we calculated the logR activity index for each star. We
compared the position of the stars in the Hertzsprung-Russell diagram to
evolutionary tracks, to estimate their mass and age. We used the lithium
abundance, derived from the Stokes I spectra, to further constrain the ages. We
obtained a definite magnetic field detection for both HD 70642 and HD 154088,
while for HD 117207 we obtained a marginal detection. Due to the lower
signal-to-noise ratio of the observations, we were unable to detect the
magnetic field in the second set of observations available for HD 117207 and HD
154088. On the basis of effective temperature, mass, age, and activity level
the three stars can be considered solar analogs. HD 70642, HD 117207, and HD
154088 are ideal targets for a comparative study between the solar magnetic
field and that of solar analogs.
