  In this paper we use the effective blackfold description of branes to extend
the study of the thermal BIon, a D-brane and parallel anti-D-brane connected by
a wormhole with F-string charge in hot flat space, by introducing a radial
boost along the brane. The boosted system behaves qualitatively differently
from both the extremal and the thermal BIon considered previously.
Interestingly, we are able to formulate a first law of thermodynamics for the
system as a whole, despite the fact that it is not a stationary blackfold. In
particular, the global temperature is given by the rest frame temperature times
the gamma factor of special relativity which is the inverse transformation
compared to the case of stationary blackfolds. In addition we define two new
kinds of thermodynamic conjugate variables, the energy flux $W$ and the
integrated velocity on the brane. We find that a phase transition occurs by
varying the energy flux $W$. Below a critical value of $W$ the brane separation
$\Delta$ changes only slightly with $W$. Instead above the critical value
$\Delta$ grows exponentially.
