Discovery of a new milli-second pulsar Toward the Bulge
ATel #17189; S. D. Hyman (SBC), N. Hurley-Walker (ICRAR), I. Joyner (SBC), J. S. Deneva (NRL), D. A. Frail (NRAO), S. Giacintucci (NRL), N. Kassim (NRL), S. J. McSweeney (ICRAR), E. Polisensky (NRL), C. M. Tan (ICRAR)
on 16 May 2025; 20:14 UT
Credential Certification: Emil Polisensky (emil.j.polisensky.civ@us.navy.mil)
We report the discovery of 1.83 ms pulsations from the source PSR J1740-2650 using the MeerKAT Array at 3 GHz. This steep spectrum (spectral index = -2.3) source was first identified as a pulsar candidate based on its earlier 150 MHz detection in the TIFR GMRT Sky Survey (TGSS), and subsequent image-based searches of the Bulge. Archival observations from the Murchison Widefield Array (200 MHz) and Australian Square Kilometre Array Pathfinder (VAST; 888 MHz) indicate PSR J1740-2650 is an eclipsing binary with a period of 9.77 hr. We estimate the DM to be 209 pc cm^-3 and distance to be 4.3 kpc. The J2000 source position is 17h 40m 16.2s, -26d 50' 29'', or (l,b) = 1.16d, +2.11d, with an uncertainty of about 1 arcsec based on the highest resolution detection (GMRT; 650 MHz). Further timing observations are planned to better characterize the properties of the pulsar and the binary orbit. The nearest gamma-ray point source is 11.7 arcmin from the pulsar's position. We encourage deep searches for X-ray and optical/IR counterparts.
