  The second pulsar catalogue of the Fermi Large Area Telescope (LAT) will
contain in excess of 100 gamma-ray pulsars. The light curves (LCs) of these
pulsars exhibit a variety of shapes, and also different relative phase lags
with respect to their radio pulses, hinting at distinct underlying emission
properties (e.g., inclination and observer angles) for the individual pulsars.
Detailed geometric modelling of the radio and gamma-ray LCs may provide
constraints on the B-field structure and emission geometry. We used different
B-field solutions, including the static vacuum dipole and the retarded vacuum
dipole, in conjunction with an existing geometric modelling code, and
constructed radiation sky maps and LCs for several different pulsar parameters.
Standard emission geometries were assumed, namely the two-pole caustic (TPC)
and outer gap (OG) models. The sky maps and LCs of the various B-field and
radiation model combinations were compared to study their effect on the
resulting LCs. As an application, we compared our model LCs with Fermi LAT data
for the Vela pulsar, and inferred the most probable configuration in this case,
thereby constraining Vela's high-altitude magnetic structure and system
geometry.
