We present the discovery of five millisecond pulsars ( MSPs ) from the PALFA Galactic plane survey using Arecibo .
Four of these ( PSRs J0557+1551 , J1850+0244 , J1902+0300 , and J1943+2210 ) are binary pulsars whose companions are likely white dwarfs , and one ( PSR J1905+0453 ) is isolated .
Phase-coherent timing solutions , ranging from \sim 1 to \sim 3 years in length , and based on observations from the Jodrell Bank and Arecibo telescopes , provide precise determinations of spin , orbital , and astrometric parameters .
All five pulsars have large dispersion measures ( > 100 pc cm ^ { -3 } , within the top 20 % of all known Galactic field MSPs ) and are faint ( 1.4 GHz flux density \stackrel { < } { { } _ { \sim } } 0.1 mJy , within the faintest 5 % of all known Galactic field MSPs ) , illustrating PALFA ’ s ability to find increasingly faint , distant MSPs in the Galactic plane .
In particular , PSR J1850+0244 has a dispersion measure of 540 pc cm ^ { -3 } , the highest of all known MSPs .
Such distant , faint MSPs are important input for accurately modeling the total Galactic MSP population .