NuSTAR Observations of the Geminga Pulsar

The Geminga pulsar (PSR J0633+1746) does not show radio pulsations yet is the second brightest gamma-ray pulsar, making it the archetype of the family of radio-quiet rotation-powered pulsars. It has an Edot of 3.26e34 erg/s with a period of 237ms at a parallax distance of 250pc and a characteristic age of 300000 years. In the soft X-rays, it shows a thermal spectrum with a faint power-law component. This power law does not connect with either the gamma-ray spectrum as measured with Fermi or the infrared. NuSTAR's large effective area above 10 keV enables the detection of the non-thermal component above the XMM-Newton detection limit. We present the preliminary results of a deep NuSTAR observation of Geminga (260 ks). The increase in the bandwidth of the non-thermal emission allows a much better characterization of the power-law component.