Variable stars in nearby galaxies III. White light observations of Field Bof IC 1613

Two nearby galaxies, IC 1613 and NGC 6822, were observed over four years to detect short period Cepheids and to obtain good light curves for Fourier d ecomposition. Since the program was carried out with a relatively small tel escope, the Dutch 0.9 m at ESO-La Silla, the observations were performed wi thout filter (white light), or W h-band; the advantage of this technique is that the photon statistics correspond to those of V-band observations of s imilar exposure time obtained with a 2-m class telescope. In this paper we discuss some properties of Wh photometry and present the results of the obs ervations of Field B in IC 1613 (3.'8x3.'8). A total of 65 images were obta ined and the reduction was performed with DAOPHOT. The light curves of 4037 stars were measured, and the analysis using various techniques allowed the detection of 121 variable stars. We detected 51 population I Cepheids, whi le previously only 12 Cepheids were known in the same field. Most of these have short periods and some are first overtone mode pulsators. The other va riable stars include one eclipsing binary, two suspected W Vir stars, 57 ir regular and semi-regular red variables, 3 periodic red variables and 6 irre gular blue variables.