Precise spectropolarimetric measurements of magnetic fields on some solar-like stars

Results of precision measurements of the net longitudinal component of magn etic held strength (B-e) performed for Procyon (alpha CMi, F5 IV-V) and thr ee solar-type stars-beta Com (GO V), zeta Her (F9 IV), beta Aql (G8 IV)are reported. All stars observed are weak solarlike activity analogs. We outlin e an improved observational technique (Stokesmeter plus CCD detector) and d ata reduction process that permits determination of the mean longitudinal f ield strength, B-e, with an accuracy within the range 1-5 G. The average va lue of B-e = -1.34 +/- 1.0 G was estimated for Procyon using 10 spectral li nes in the region 6285-6350 Angstrom. A substantial magnetic field value wa s detected on only one occasion for zeta Her: B-e = - 10.1 +/- 3.1 G.