Speaker
Description
The AWAKE experiment [1] will be taking data over the next two years
to establish the method of proton-driven plasma wakefield
acceleration. An R&D programme is being formulated for post-LS2 in
which the AWAKE experiment demonstrates [2] that bunches of about $10^9$
electrons with an energy of 10 GeV accelerated in about 10 m of
plasma are achievable and that the energy gain is scalable with
length. Given a clean electron beam of O(50 GeV) and of a much higher
rate than from the SPS secondary beam, new and improved fixed-target
or beam-dump experiments are possible. An example is the NA64
experiment [3] which is searching for hidden sector physics such as
dark photons using the secondary SPS electron beam at an intensity
of $\sim 10^6$ $e^-/{\rm s}$. With the expectation of being able to increase this
rate by at least a factor of 100 using the AWAKE beam, sensitivity to
new physics is correspondingly extended. An electron beam of
O(50 GeV) is also planned for the LHeC which under the AWAKE scheme
could be achieved in a plasma cell of ~50 m in length, although with
modest luminosities. This could open up the
possibility of an LHeC-type project at relatively low cost and
focusing on physics at low Bjorken-$x$ such as saturation and QCD in
general. An ultimate goal of the AWAKE technology is to use it to
produce an electron beam of 3 TeV and collide with an LHC proton
beam. This very high energy electron-proton collider [4] would
probe a completely new regime in which QCD and the structure of
matter is completely unknown. Again, this would be relatively low
luminosity, but this is offset by the rapidly rising cross sections
at low Bjorken $x$.
[1] AWAKE Coll., arXiv:1511.09032; arXiv:1512.05498
[2] E. Adli (AWAKE Coll.), IPAC2016 proceedings, p.2557-2560.
[3] https://na64.web.cern.ch
[4] A. Caldwell and M. Wing, arXiv:1606.00783
