We report the discovery of three new pulsars in the globular cluster(GC)NGC 6517,namely NGC 6517 E,F and G,made with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).The spin periods of NGC 6517 E,F and...We report the discovery of three new pulsars in the globular cluster(GC)NGC 6517,namely NGC 6517 E,F and G,made with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).The spin periods of NGC 6517 E,F and G are 7.60 ms,24.89 ms and 51.59 ms,respectively.Their dispersion measures are 183.29,183.713 and 185.3 pc cm^(-3),respectively,all slightly larger than those of the previously known pulsars in this cluster.The spin period derivatives are at the level of 1×10^(-18) s s^(-1),which suggests these are recycled pulsars.In addition to the discovery of these three new pulsars,we updated the timing solutions of the known isolated pulsars,NGC 6517 A,C and D.The solutions are consistent with those from Lynch et al.but with smaller timing residuals.From the timing solution,NGC6517 A,B(position from Lynch et al.),C,E and F are very close to each other on the sky and only a few arcseconds from the optical core of NGC 6517.With currently published and unpublished discoveries,nine pulsars have been discovered in NGC 651,ranking it 6 thfor GCs with the most known pulsars.The discoveries take advantage of the high sensitivity of FAST and a new algorithm used to check and filter possible candidate signals.展开更多
基金supported by the Basic Science Center Project of the National Natural Science Foundation of China(NSFC,Grant Nos.11703047,11773041 and U2031119)supported by the CAS“Light of West China”Program+1 种基金supported by the Youth Innovation Promotion Association of CAS(id.2018075)supported by the NSF Physics Frontiers Center award 1430284。
文摘We report the discovery of three new pulsars in the globular cluster(GC)NGC 6517,namely NGC 6517 E,F and G,made with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).The spin periods of NGC 6517 E,F and G are 7.60 ms,24.89 ms and 51.59 ms,respectively.Their dispersion measures are 183.29,183.713 and 185.3 pc cm^(-3),respectively,all slightly larger than those of the previously known pulsars in this cluster.The spin period derivatives are at the level of 1×10^(-18) s s^(-1),which suggests these are recycled pulsars.In addition to the discovery of these three new pulsars,we updated the timing solutions of the known isolated pulsars,NGC 6517 A,C and D.The solutions are consistent with those from Lynch et al.but with smaller timing residuals.From the timing solution,NGC6517 A,B(position from Lynch et al.),C,E and F are very close to each other on the sky and only a few arcseconds from the optical core of NGC 6517.With currently published and unpublished discoveries,nine pulsars have been discovered in NGC 651,ranking it 6 thfor GCs with the most known pulsars.The discoveries take advantage of the high sensitivity of FAST and a new algorithm used to check and filter possible candidate signals.