Session C02: Accelerators for Nuclear Physics Research: Status and Plans

EIC Design and Challenges for eRHIC

The US Nuclear Physics community strongly endorses the construction of an Electron-Ion Collider. This facility would provide unique opportunities to study how QCD implies nuclear structure, spatial distributions of gluons, formation of the nuclear spin and the saturation of gluon density in the nucleus and the nuclides. There are two different approaches being worked out to pave the path for such a collider with a luminosity of L$=$1E34/cm2/s, a center of mass energy range between 20 GeV and 140 GeV, and with both ion and electron beams polarized. Both solutions, one studied at Jefferson Laboratory, the other studied at Brookhaven National Laboratory are based on a high current double ring collider with a crossing angle collision geometry and strong hadron cooling which exceeds presently achieved cooling rates at high energy by at least two orders of magnitude. The report will describe the accelerator physics challenges of the EIC and then will give an overview of the designs of JLEIC being proposed by Jefferson Laboratory and the design of the eRHIC Electron Ion Collider being proposed by Brookhaven National Laboratory.   

EIC Design and Challenges for JLEIC

A high luminosity high polarization electron-ion collider with a center-of-mass energy range of 20 to 140 GeV was recommended by the 2015 NSAC Long Range Plan as the next accelerator facility to be built in the US for reaching the QCD frontier. At Jefferson Lab, the design study of such an electron-ion collider, JLEIC, based on the existing 12 GeV CEBAF SRF linac, has been actively pursued over the last ten years. JLEIC utilizes high bunch repetition colliding beams for achieving high luminosity up to 2x1034 /cm2/s. JLEIC also adopts a figure-8 shape for the two collider rings as well as the ion booster for its advantage in preserving high beam polarization. The JLEIC interaction region design was optimized to enable full acceptance particle detection. In this talk, I will give an overview of the JLEIC baseline design and also discuss the accelerator R&D challenges.\\ \\Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.   

FRIB Facility Goals, Status, and Plans

The Facility for Rare Isotope Beams (FRIB) is a major new scientific user facility under construction on the campus of the Michigan State University in USA for nuclear science research with beams of rare isotopes. With a total construction cost of \$730 million, the project has passed the 80\% complete mark and is managed toward early completion in 2021. FRIB is estimated to provide access to 80\% of all isotopes of elements lighter than uranium. With an average beam power two orders of magnitude higher than operating heavy-ion facilities, FRIB stands at the power frontier of the accelerator family. This paper summarizes the goals, status of design, technology development, construction, and commissioning, as well as plans of operations and upgrades.