Arecibo pulsar survey using ALFA. I. Survey strategy and first discoveries

摘要: We report results from the initial stage of a long-term pulsar survey Galactic plane using Arecibo L-band Feed Array (ALFA), seven-beam receiver operating at 1.4 GHz with 0.3 bandwidth, and fast-dump digital spectrometers. The search targets low latitudes, |b| 5°, in accessible longitude ranges 32° l 77° 168° 214°. instrumentation, data processing, observations, sensitivity, database management are described. Data discussed here were collected over 100 MHz passband centered on 1.42 spectrometer that recorded 256 channels every 64 μs. Analysis their full time frequency resolutions is ongoing. Here we preliminary, low-resolution analysis for which decimated to speed up processing. have detected 29 previously known pulsars discovered 11 new ones. One these, PSR J1928+1746, period 69 ms relatively characteristic age 82 kyr, plausible candidate association unidentified EGRET source 3EG J1928+1733. Another, J1906+07, nonrecycled relativistic binary an orbital 3.98 hr. In parallel periodicity analysis, also isolated dispersed pulses. This technique has resulted discovery J0628+09, extremely sporadic radio emitter spin 1.2 s. Simulations carried out indicate ~1000 will be found our ALFA survey. addition providing large sample use population analyses probing magnetoionic interstellar medium, maximizes chances finding rapidly spinning millisecond compact systems. Our algorithms exploit multiple streams discriminate between interference celestial signals, including possibly classes transient sources.