Presentation #226.04 in the session Pulsars and Radio Transients.
We present the results of 18 months of timing measurements of the planets pulsar, PSR B1257+12, with the Arecibo radio telescope at 327, 430, and 1400 MHz. The goal of this project was to demonstrate that high cadence, high timing precision observations may be the best way to search for low-mass, compact orbit planets around millisecond pulsars, and to see, if additional planets of this kind could be present in the PSR B1257+12 system. Although no new planets have been found, our precise measurements of the dispersion measure variations of the pulsar reveal a significant correlation with the Keplerian pattern in the pulse arrival times due to the presence of the two superEarth–mass planets. We suggest that this correlation can be explained in terms of a possible pulsar wind–planet interaction.