Plucking the Web: Searching Unidentified Gamma-ray Sources for Spider Pulsars using Jerksearch Algorithm

Binary millisecond pulsars (MSPs) can be used to study a wide variety of scientific phenomenon including the testing and constraining of General Relativity, Equation of State of nuclear matter, and properties of matter at extreme densities. Finding new MSPs is one of the main science drivers of current pulsar surveys. In the past decade, the most successful approach to search for MSPs has been to use acceleration searches to look for radio pulsations in the error bars of Gamma-ray sources identified by the Large Area Telescope (LAT) aboard the Fermi Satellite. However, 1000s of gamma-ray sources found by LAT still remain unassociated with any astrophysical object. It is believed that many of these could be MSPs. One of the reasons for their non-detection is the use of acceleration searches to account for the orbital motion of the pulsar. This method is ineffective when the observation time is longer than 1/10th of the orbital period. Due to the fact that sensitivity to pulses is directly proportional to the observation time, fainter systems in very tight orbits have remained outside the parameter space of such searches.We have been using the novel jerksearch algorithm implemented in the PRESTO software package to re-search Fermi sources that remain unidentified. Jerksearch is sensitive to changes in the period of the pulsed signal caused by the second derivative of the orbital period, resulting in increased sensitivity to tight binary systems. Hence, we are searching in a parameter space which has scarcely been searched till now without making a compromise on sensitivity. We are using radio data gathered from the Robert C. Byrd Green Bank Telescope (GBT) at 820 MHz for unassociated sources from Fermi LAT catalogs as part of the Fermi Pulsar Search Collaboratory. We expect to find multiple millisecond pulsar binaries, including spider systems and maybe even a black hole-pulsar binary system. We are using the Dalma High Performance Computing (HPC) cluster of NYUAD to run the computationally expensive jerksearches. Here we present preliminary results of these searches, showing several promising candidates which will potentially be followed up using the GBT.