  Coronal bright fronts (CBFs) are large scale wavefronts that propagate though
the solar corona at hundreds of kilometers per second. While their kinematics
have been studied in detail, many questions remain regarding the temporal
evolution of their amplitude and pulse width. Here, contemporaneous high
cadence, multi-thermal observations of the solar corona from the Solar Dynamic
Observatory (SDO) and Solar TErrestrial RElations Observatory (STEREO)
spacecraft are used to determine the kinematics and expansion rate of a CBF
wavefront observed on 2010 August 14. The CBF was found to have a lower initial
velocity with weaker deceleration in STEREO observations compared to SDO (~340
km/s and -72 m/s/s as opposed to ~410 km/s and -279 m/s/s). The CBF kinematics
from SDO were found to be highly passband-dependent, with an initial velocity
ranging from 379+/-12 km/s to 460+/-28 km/s and acceleration ranging from
-128+/-28 m/s/s to -431+/-86 m/s/s in the 335A and 304A passbands respectively.
These kinematics were used to estimate a quiet coronal magnetic field strength
range of ~1-2 G. Significant pulse broadening was also observed, with expansion
rates of ~130 km/s (STEREO) and ~220 km/s (SDO). By treating the CBF as a
linear superposition of sinusoidal waves within a Gaussian envelope, the
resulting dispersion rate of the pulse was found to be ~8-13 Mm^2 s^-1. These
results are indicative of a fast-mode magnetoacoustic wave pulse propagating
through an inhomogeneous medium.
