【摘 要】
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High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars.Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) during its commissioning phase,we have carried out a number of t
【机 构】
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CAS Key Laboratory of FAST,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 1
【出 处】
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中国科学：物理学 力学 天文学（英文版）
论文部分内容阅读
High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars.Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) during its commissioning phase,we have carried out a number of targeted deep searches of Fermi Large Area Telescope (LAT) γ-ray sources.On February 27,2018 we discovered an isolated mil-lisecond pulsar (MSP),PSR J0318+0253,coincident with the unassociated γ-ray source 3FGL J0318.1 +0252.PSR J0318+0253 has a spin period of 5.19 ms,a dispersion measure (DM) of 26 pc cm-3 corresponding to a DM distance of about 1.3 kpc,and a period-averaged flux density of (～ 11 +2) μJY at L-band (1.05-1.45 GHz).Among all high energy MSPs,PSR J0318+0253 is the faintest ever detected in radio bands,by a factor of at least ～4 in terms of L-band fluxes.With the aid of the radio ephemeris,an analysis of 9.6 years of Fermi-LAT data revealed that PSR J0318+0253 also displays strong γ-ray pulsations.Follow-up observa-tions carried out by both Arecibo and FAST suggest a likely spectral turn-over around 350 MHz.This is the first result from the collaboration between FAST and the Fermi-LAT teams as well as the first confirmed new MSP discovery by FAST,raising hopes for the detection of many more MSPs.Such discoveries will make a significant contribution to our understanding of the neutron star zoo while potentially contributing to the future detection of gravitational waves,via pulsar timing array (PTA) experiments.
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