Optimizing the Next GBT Pulsar Survey

Large-area pulsar surveys are important tools for increasing the population of known pulsars, which are used to study various extreme physical phenomena. As the current large-scale survey on the Robert C. Bryd Green Bank Telescope (GBT), the Green Bank North Celestial Cap (GBNCC) survey approaches completion, it is important to begin planning next-generation pulsar surveys that are competitive with current and upcoming pulsar surveys conducted on other instruments. We present the results of simulated pulsar population and survey studies conducted for potential GBT pulsar surveys using the 820 MHz, L-Band, S-Band, Ultra-wide band, and the Focal L-Band Array for the GBT (FLAG) receivers. We determined that a survey over 1700 square degree region along the Galactic plane would be the most effective. Such a survey conducted at frequencies of 1.1 to 1.9 GHz using the GBT L-Band receiver would detect approximately 500 new pulsars, about 50 of which would be MSPs. We also compare these results to a possible survey with the FLAG receiver over the same region with a 1260 s dwell time, which is projected to discover 550 pulsars. Radio frequency interference would likely reduce the true yields to some degree. While a FLAG survey results in a slightly higher yield, we favor the L-Band receiver survey because it would be more sensitive to binary pulsars in short orbital periods. However, expanding the instantaneous bandwidth or field of view of FLAG could make it the better option.