TUPPM1R1
ANL, Lemont, Illinois, USA
Stochastic cooling of electrons and positrons using their extreme ultraviolet radiation is considered. A few beneficial modifications of a stochastic cooling technique are described – a petaherz-scale bandwidth, ability to apply many uncorrelated corrections to particle offsets in one cooling system, cascade amplified stochastic cooling – all resulting in a simpler and more flexible cooling system producing fast cooling without the amplifier. This approach to cooling electron and positron beams easily outperforms radiation cooling in preparing low-emittance and low-energy-spread beams in moderate-energy storage rings. An option for using this technique to maintain a "cold" electron beam for an electron cooling of protons in Electron Ion Collider is considered.
ANL, Lemont, Illinois, USA
RadiaSoft LLC, Boulder, Colorado, USA
Coherent electron cooling* using a plasma-cascade amplifier (PCA)** can provide significantly faster cooling of hadrons than the conventional microwave stochastic cooling due to a wide bandwidth of a pickup, a kicker, and an amplifier. The PCA creates unstable plasma oscillations by modulating the plasma frequency by varying the transverse beam size along the beam line. An alternative approach to the amplifier studied in this work is to modulate the plasma frequency by a sequence of wiggler magnets separated by weak chicanes. We present a new derivation of the amplifier spectral gain function following the initial analysis presented in ***. Numerical simulations of the gain function were also done using electron beam parameters projected for the Electron Ion Collider. The numerical results consistently show higher gains than those obtained using the analytical gain function.
* V. Litvinenko, Ya. Derbenev, Phys. Rev. Lett., 102, (2009)114801.
** V. Litvinenko et al., Phys. Rev. Accel. Beams, 24, (2021)014402.
*** G. Stupakov, A. Zholents, COOL2021