The Green Bank Northern Sky Survey: Discovery of a New Neutron Star-Neutron Star Binary

Extract

We have surveyed 15,900 deg² of the northern sky for millisecond pulsars at 370 MHz with the Green Bank 140ft telescope. The telescope was driven along lines of constant declination such that a given point on the sky was observed for two minutes. A Fourier transform spectrometer synthesized 512-channel spectra across 40 MHz in each of two polarizations. Total intensity levels were boxcar averaged at intervals of 256 μs, quantized to 1 bit, and written to tape. Data were processed with the Cray C90 of the Pittsburgh Supercomputer Center. The flux limit of the survey was 8 mJy for slow pulsars. A further 1500 deg² were observed with 20 MHz bandwidth, yielding 71% the usual sensitivity.

Eighty-four slow pulsars were detected, of which six were previously unknown. Three recycled pulsars were detected: the relativistic binary B1534+12; the neutron star-white dwarf binary J1022+1001, discovered nearly simultaneously at Arecibo; and J1518+4904, a previously unknown pulsar with a 41 ms rotation period.