  We demonstrate that cross-field transport in the scrape-off layer (SOL) can
be moderately increased by electromagnetic effects in high-beta regimes,
resulting in a broader electron heat-flux width on the endplates. This
conclusion is taken from full-$f$ electromagnetic gyrokinetic simulations of a
helical SOL model that roughly approximates the SOL of the National Spherical
Torus Experiment (NSTX). The simulations have been performed with the Gkeyll
code, which recently became the first code to demonstrate the capability to
simulate electromagnetic gyrokinetic turbulence on open magnetic field lines
with sheath boundary conditions. We scan the source rate and thus $\beta$ so
that the normalized pressure gradient (the MHD ballooning parameter $\alpha
\propto \partial \beta / \partial r \propto \beta / L_p$) is scanned over an
experimentally-relevant range, $\alpha = 0.3-1.5$. While there is little change
in the pressure gradient scale length $L_p$ near the midplane as beta is
increased, a 10% increase in cross-field transport near the midplane results in
an increase in the electron heat-flux width $\lambda_q$ and a 25% reduction of
the peak electron heat flux to the endplates.
