Title: R&D On Beam Injection and Bunching Schemes In The Fermilab Booster,
Abstract: Fermilab is committed to upgrade its accelerator complex to support HEP
experiments at the intensity frontier. The ongoing Proton Improvement Plan
(PIP) enables us to reach 700 kW beam power on the NuMI neutrino targets. By
the end of the next decade, the current 400 MeV normal conducting LINAC will be
replaced by an 800 MeV superconducting LINAC (PIP-II) with an increased beam
power >50% of the PIP design goal. Both in PIP and PIP-II era, the existing
Booster is going to play a very significant role, at least for next two
decades. In the meanwhile, we have recently developed an innovative beam
injection and bunching scheme for the Booster called "early injection scheme"
that continues to use the existing 400 MeV LINAC and implemented into
operation. This scheme has the potential to increase the Booster beam intensity
by >40% from the PIP design goal. Some benefits from the scheme have already
been seen. In this paper, I will describe the basic principle of the scheme,
results from recent beam experiments, our experience with the new scheme in
operation, current status, issues and future plans. This scheme fits well with
the current and future intensity upgrade programs at Fermilab.