A very cold disc of dust around the G0V star HD 207129

We present ISO observations made between 2.5 and 180 mu m of the nearby G0V dwarf HD 207129 taken as part of a large survey of nearby main-sequence st ars in search of debris discs. HD 207129 emits radiation in excess of the p hotospheric flux density between at least 60 and 180 mu m. The infrared exc ess is explained by a disc of cold dust particles (25 to 50 K) and, to acco unt for the absence of a significant 25 mu m excess, the disc must have a c entral hole of several 100 AU radius. We discuss various models and show ho w the disc will evolve in time under the influence of radiation pressure an d Poynting-Robertson drift. The presence of the large hole suggests that HD 207129 has at least one planet.