The orbital parameters of three new subdwarf B binaries

We determine the orbital parameters of the three subdwarf B (sdB) stars, PG 0101+039, PG 1432+159 and PG 2345+318, We find orbital periods of 13.6778 /- 0,0002, 5.398 +/- 0.008 and 5.7827 +/- 0.0002 h, respectively. We calcul ate lower limits for the mass of the companion star in each case. We also s uggest upper mass limits for the companions to PG 1432+159 and PG 2345+318 on the basis of the maximum size of the companion allowed by the Roche lobe geometry. The nature of the companion star is discussed but cannot be dete rmined without further observations. We confirm the previously measured per iod for the sdB binary PG 1101+249 as 8.49 h.