DISCOVERY OF A HIGHLY ENERGETIC PULSAR ASSOCIATED WITH IGR J14003-6326 IN THE YOUNG UNCATALOGED GALACTIC SUPERNOVA REMNANT G310.6-1.6

We report the discovery of 31.18 ms pulsations from the INTEGRAL source IGR J14003-6326 using the Rossi Xray Timing Explorer (RXTE). This pulsar is most likely associated with the bright Chandra X-ray point source lying at the center of G310.6-1.6, a previously unrecognized Galactic composite supernova remnant (SNR) with a bright central non-thermal radio and X-ray nebula, taken to be the pulsar wind nebula (PWN). PSR J1400-6325 is amongst the most energetic rotation-powered pulsars in the Galaxy, with a spin-down luminosity of (E) over dot = 5.1 x 1037 erg s(-1). In the rotating dipole model, the surface dipole magnetic field strength is B-s = 1.1 x 1012 G and the characteristic age tau(c) equivalent to P/2(P) over dot = 12.7 kyr. The high spin-down power is consistent with the hard spectral indices of the pulsar and the nebula of 1.22 +/- 0.15 and 1.83 +/- 0.08, respectively, and a 2-10 keV flux ratio F-PWN/F-PSR similar to 8. Followup Parkes observations resulted in the detection of radio emission at 10 and 20 cm from PSR J1400-6325 at a dispersion measure of similar to 560 cm(-3) pc, which implies a relatively large distance of 10 +/- 3 kpc. However, the resulting location off the Galactic plane of similar to 280 pc would be much larger than the typical thickness of the molecular disk, and we argue that G310.6-1.6 lies at a distance of similar to 7 kpc. There is no gamma-ray counterpart to the nebula or pulsar in the Fermi data published so far. A multi-wavelength study of this new composite SNR, from radio to very high-energy gamma rays, suggests a young (less than or similar to 10(3) yr) system formed by a sub-energetic (less than or similar to 10(50) erg), low ejecta mass (M-ej similar to 3 M-circle dot) supernova explosion that occurred in a low-density environment (n(0) similar to 0.01 cm(-3)).