  Sgr A East is a very prominent elongated shell structure surrounding (though
off-centered from) the Galactic nucleus. Its energetics (~4x10^52 ergs), based
on the power required to carve out the radio synchrotron remnant within the
surrounding dense molecular cloud, appear to be extreme compared to the total
energy (~10^51 ergs) released in a typical supernova (SN) explosion. Yet it
shares several characteristics in common with SN remnants (SNRs), the most
significant of which is the ~0.1-10 GeV gamma-ray spectrum measured by EGRET,
if we associate the Galactic center source 2EGJ1746-2852 with this nonthermal
shell. We here show that the highest-energy component in Sgr A East's spectrum,
like that of SNRs, can be fitted with the gamma-rays produced in neutral pion
decays. Further, we demonstrate in a self-consistent manner that the leptons
released in the associated charged pion decays produce an e+e- distribution
that can mimic a power-law with index ~3, like that inferred from the VLA data
for this source. These relativistic electrons and positrons also radiate by
bremsstrahlung, and inverse Compton scattering with the intense IR and UV
fields from the nucleus. We show that the overall emissivity calculated in this
way may account for Sgr A East's broadband spectrum ranging from GHz
frequencies all the way to TeV energies, where Whipple has thus far set an
upper limit to the flux corresponding to a 2.5-sigma signal above the noise.
