OBSERVATIONS OF ENERGETIC HIGH MAGNETIC FIELD PULSARS WITH THE FERMI LARGE AREA TELESCOPE

We report the detection of Delta *g-ray pulsations from the high-magnetic-field rotation-powered pulsar PSR J1119--6127 using data from the Fermi Large Area Telescope. The Delta *g-ray light curve of PSR J1119--6127 shows a single, wide peak offset from the radio peak by 0.43 ? 0.02 in phase. Spectral analysis suggests a power law of index 1.0 ? 0.3+0.4 -- 0.2 with an energy cutoff at 0.8 ? 0.2+2.0 -- 0.5 GeV. The first uncertainty is statistical and the second is systematic. We discuss the emission models of PSR J1119--6127 and demonstrate that despite the object's high surface magnetic field--near that of magnetars--the field strength and structure in the Delta *g-ray emitting zone are apparently similar to those of typical young pulsars. Additionally, we present upper limits on the Delta *g-ray pulsed emission for the magnetically active PSR J1846--0258 in the supernova remnant Kesteven 75 and two other energetic high-B pulsars, PSRs J1718--3718 and J1734--3333. We explore possible explanations for the non-detection of these three objects, including peculiarities in their emission geometry.