Tyrel J. Johnson, Alice K. Harding, Christo Venter
Pulsed gamma rays have been detected with the Fermi Large Area Telescope
(LAT) from more than 20 millisecond pulsars (MSPs), some of which were
discovered in radio observations of bright, unassociated LAT sources. We have
fit the radio and gamma-ray light curves of 19 LAT-detected MSPs in the context
of geometric, outer-magnetospheric emission models assuming the retarded vacuum
dipole magnetic field using a Markov chain Monte Carlo maximum likelihood
technique. We find that, in many cases, the models are able to reproduce the
observed light curves well and provide constraints on the viewing geometries
that are in agreement with those from radio polarization measurements.
Additionally, for some MSPs we constrain the altitudes of both the gamma-ray
and radio emission regions. The best-fit magnetic inclination angles are found
to cover a broader range than those of non-recycled gamma-ray pulsars.
View original:
http://arxiv.org/abs/1110.5476
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