Discovery of a Highly Energetic X-ray Pulsar Powering HESS J1813-178 in the Young Supernova Remnant G12.82-0.02

TL;DR

This paper reports the discovery of a highly energetic X-ray pulsar, PSR J1813-1749, which powers the TeV source HESS J1813-178, providing insights into its properties, energy conversion efficiency, and potential origin in a young stellar cluster.

Contribution

The discovery of a new, highly energetic pulsar associated with a supernova remnant and TeV emission, with detailed measurements of its properties and energy conversion efficiency.

Findings

Pulsar has a 44.7 ms period and is the second most energetic in the Galaxy.

The pulsar's spin-down luminosity is approximately 6.8 x 10^37 erg/s.

The pulsar's energy conversion efficiency to X-ray and TeV emissions is around 0.03% to 0.07%.

Abstract

We report the discovery of 44.7 ms pulsations from the X-ray source CXOU J181335.1-174957 using data obtained with the XMM-Newton Observatory. PSR J1813-1749 lies near the center of the young radio supernova remnant G12.82-0.02, which overlaps the compact TeV source HESS J1813-178. This rotation-powered pulsar is the second most energetic in the Galaxy, with a spin-down luminosity of Edot = (6.8 +/- 2.7)E37 erg/s. In the rotating dipole model, the surface dipole magnetic field strength is B_s = (2.7 +/- 0.6)E12 G and the spin-down age of 3.3-7.5 kyr, consistent with the location in the small, shell-type radio remnant. At an assumed distance of 4.7 kpc by association with an adjacent young stellar cluster, the efficiency of PSR J1813-1749 in converting spin-down luminosity to radiation is approx. 0.03% for its 2-10 keV flux, approx. 0.1% for its 20-100 keV INTEGRAL flux, and approx. 0.07% for the >200 GeV emission of HESS J1813-178, making it a likely power source for the latter. The nearby young stellar cluster is possibly the birthplace of the pulsar progenitor, as well as an additional source of seed photons for inverse Compton scattering to TeV energies.