CHAMP Cosmic Rays
  We study interactions of cosmological relics, $X$, of mass $m$ and electric
charge $qe$ in the galaxy, including thermalization with the interstellar
medium, diffusion through inhomogeneous magnetic fields and Fermi acceleration
by supernova shock waves. We find that for $m \mathop{}_{\textstyle
\sim}^{\textstyle <} 10^{10} q \; ~{\rm GeV}$, there is a large flux of
accelerated $X$ in the disk today, with a momentum distribution $\propto
1/p^{2.5}$ extending to $(\beta p)_{max} \sim 5 \times10^4 q \; ~{\rm GeV}$.
Even though acceleration in supernova shocks is efficient, ejecting $X$ from
the galaxy, $X$ are continually replenished by diffusion into the disk from the
halo or confinement region. For $m \mathop{}_{\textstyle \sim}^{\textstyle >}
10^{10} q \; ~{\rm GeV}$, $X$ cannot be accelerated above the escape velocity
within the lifetime of the shock. The accelerated $X$ form a component of
cosmic rays that can easily reach underground detectors, as well as deposit
energies above thresholds, enhancing signals in various experiments. We find
that nuclear/electron recoil experiments place very stringent bounds on $X$ at
low $q$; for example, $X$ as dark matter is excluded for $q$ above $10^{-9}$
for any $m$. For larger $q$, stringent bounds on the fraction of dark matter
that can be $X$ are set by Cherenkov and ionization detectors. Nevertheless,
very small $q$ is highly motivated by the kinetic mixing portal, and we
identify regions of $(m,q)$ that can be probed by future experiments.
