  Magnetic reconnection is an explosive energy-release process in laboratory,
space and astrophysical plasmas. While magnetic fields can `break' and
`reconnect' in a very small region called the electron diffusion region (EDR),
there have been conflicting theories as to whether this region can be a place
of rapid energization of plasmas. Here we report a fortuitous encounter of the
EDR by THEMIS in the Earth's magnetotail where significant heating and
demagnetization of electrons were observed. Additional energization was
observed on both sides (immediate upstream and downstream) of the EDR, leading
to a total of more than an order of magnitude energization across this region.
The results demonstrate that, despite its minuscule size, the EDR does indeed
contribute to the overall process of electron energization via magnetic
reconnection.
