  This paper presents results obtained from Stokes I and V spectra of the B2Vp
star sigma Ori E, observed by both the Narval and ESPaDOnS spectropolarimeters.
Using Least- Squares Deconvolution, we investigate the longitudinal magnetic
field at the current epoch, including period analysis exploiting current and
historical data. sigma Ori E is the prototypical helium-strong star that has
been shown to harbor a strong magnetic field, as well as a magnetosphere,
consisting of two clouds of plasma forced by magnetic and centrifugal forces to
co-rotate with the star on its 1.19 day period. The Rigidly Rotating
Magnetosphere (RRM) model of Townsend & Owocki (2005) approximately reproduces
the observed variations in longitudinal field strength, photometric brightness,
Halpha emission, and various other observables. There are, however, small
discrepancies between the observations and model in the photometric light
curve, which we propose arise from inhomogeneous chemical abundances on the
star's surface. Using Magnetic Doppler Imaging (MDI), future work will attempt
to identify the contributions to the photometric variation due to abundance
spots and due to circumstellar material.
