SIMBAD references

During a systematic search for periodic signals in a sample of ∼3000 ROSAT HRI (0.1-2.4keV) light curves, we discovered ∼321s pulsations in the X-ray flux of RX J0806.3+1527. Two different HRI observations of RX J0806.3+1527 were obtained with the source at flux level of 3 and 5x10^–12erg/cm²/s, respectively. Only a faint B=20.5 object is possibly present within the error circle, while no optical counterpart is present in the R plate down to a limiting magnitude of ∼20. This indicates that the object is intrinsically blue. The X-ray and optical findings imply that RX J0806.3+1527 is a relatively distant (∼500pc) intermediate polar (IP) or, more unlikely, a nearby (∼10pc) isolated neutron star accreting from the interstellar medium.