MOB2IO02
JLab, Newport News, Virginia, USA
An Electron Ion Collider (EIC) has been identified in the Nuclear Physics Long Range Plan as the priority facility for new construction. This talk presents the overview and status of the Jefferson Lab design of an EIC (JLEIC). It features frequent collisions of small electron and ion bunches providing a luminosity of 1033-1034 cm-1s-1 in a broad range of the center-of-mass energy. The small size of ion bunches is maintained against intra-beam scattering by a novel high-energy bunched beam electron cooling system. The figure-8 shape of the electron and all ion rings allows for preservation and ease of manipulation of the electron polarization and the spin of any ion species. The interaction region is designed to accommodate a full-acceptance detector with complete coverage and geometry tagging in the forward and ultra-forward directions. The talk highlights recent progress in the JLEIC accelerator design and various aspects of R&D including the electron and ion complexes, integrated interaction region design, optimization of non-linear dynamics, electron and light ion polarization schemes, RF systems, crab crossing scheme, high-energy electron cooling, and magnet design.
JLab, Newport News, Virginia, USA
SLAC, Menlo Park, California, USA
Self Employment, Private address, USA
The JLEIC is proposed as a next-generation facility for the study of strong interaction (QCD). Achieving its goal luminosity of up to 1034 cm-2s−1 requires good dynamical properties and a large dynamic aperture (DA) of ~ ±10 σ of the beam size. The limit on the DA comes primarily from non-linear dynamics, element misalignments, magnet multipole components, and detector solenoid effect. This paper presents a complete simulation including all of these effects. We first describe an orbit correction scheme and determine tolerances on element misalignments. And beta beat, betatron tunes, coupling, and linear chromaticity perturbations also be corrected. We next specify the requirements on the multipole components of the interaction region magnets, which dominate the DA in the collision mode. Finally, we take special care of the detector solenoid effects. Some of the complications are an asymmetric design necessary for a full acceptance detector with a crossing angle of 50 mrad. Thus, in addition to coupling, the solenoid causes closed orbit excursion and excites dispersion. It also breaks the figure-8 spin symmetry. We present a scheme with correction of all of these effects.
ANL, Argonne, Illinois, USA
JLab, Newport News, Virginia, USA
The current baseline design for the JLab EIC (JLEIC) ion accelerator complex is based on a pulsed superconducting linac, an 8-GeV booster followed by a dual function 20-100 GeV booster and collider ring. Both the 8-GeV booster and collider ring will use super-ferric magnets with fields up to 3 Tesla. We here propose an alternative cost-effective and low-risk design where the 8-GeV booster is replaced with a more compact 3-GeV booster using room-temperature magnets. The electron storage ring, which is part of the electron complex, will also serve as large booster for the ions, up to 11 GeV. We also propose two stages for the JLEIC. A first low-energy stage up to 60 GeV, where room-temperature magnets (up to 1.6 Tesla) will be used for the ion collider ring, to be later replaced with 6 Tesla superconducting magnets in a second stage of the project providing up to 200 GeV energy. In this second stage, the 1.6 T room-temperature magnets will replace the PEP-II magnets in the electron storage ring to boost the ions to higher energies (25 GeV or higher) for appropriate injection into the higher energy collider. Details and feasibility of the proposed plan will be presented and discussed.
JLab, Newport News, Virginia, USA
SLAC, Menlo Park, California, USA
Self Employment, Private address, USA
The short lengths of colliding bunches in the proposed Jefferson Lab Electron-Ion Collider (JLEIC) allow for small beta-star values at the interaction point (IP) yielding a high luminosity. The strong focusing associated with the small beta-stars results in high natural chromaticities and potentially a beam smear at the IP. Rapid growth of the electron equilibrium emittances and momentum spread with energy further complicates the situation. We investigated nonlinear dynamics correction schemes that overcome these problems and allow for stable beam dynamics and sufficient beam lifetime at the highest electron energy. In this paper, we present and compare tracking simulation results for various schemes considering their emittance contributions.
JLab, Newport News, Virginia, USA
MIPT, Dolgoprudniy, Moscow Region, Russia
Science and Technique Laboratory Zaryad, Novosibirsk, Russia
The figure-8 JLEIC collider ring opens wide possibilities for manipulating proton and deuteron spin directions during an experiment. Using 3D spin rotators, one can, at the same time, efficiently control the polarization direction as well as the spin tune value. The 3D spin rotators allow one to arrange a system for reversals of the spin direction in all beam bunches during an experiment, i.e. a spin-flipping system. To preserve the polarization, one has to satisfy the condition of adiabatic change of the spin direction. When adjusting the polarization direction, one can stabilize the spin tune value, which completely eliminates resonant beam depolarization during the spin manipulation process. We provide the results of numerical modeling of a spin-flipping system in the JLEIC ion collider ring. The presented results demonstrate the feasibility of organizing a spin-flipping system using a 3D rota-tor. The figure-8 JLEIC collider provides a unique capability of doing high-precision experiments with polarized ion beams.
SLAC, Menlo Park, California, USA
JLab, Newport News, Virginia, USA
Self Employment, Private address, USA
The Jefferson Lab Electron-Ion Collider (JLEIC) is being designed to achieve a high luminosity of up to 1034 1/(cm2*sec). The latter requires a small beam size at the interaction point demanding a strong final focus (FF) quadrupole system. The strong beam focusing in the FF unavoidably creates a large chromaticity which has to be compensated in order to avoid a severe degradation of momentum acceptance. This has to be done while preserving sufficient dynamic aperture. An additional design requirement for the chromaticity compensation optics in the electron ring is preservation of the low beam emittance. This paper reviews the development and selection of a chromaticity correction scheme for the electron collider ring.
JLab, Newport News, Virginia, USA
GWU, Washington, USA
UCR, Riverside, California, USA
Muons, Inc, Illinois, USA
Skew Parametric-resonance Ionization Cooling (Skew PIC) is an extension of the Parametric-resonance Ionization Cooling (PIC) framework that has previously been explored as the final 6D cooling stage of a high-luminosity muon collider. The addition of skew quadrupoles to the PIC magnetic focusing channel induces coupled dynamic behavior of the beam that is radially periodic. The periodicity of the radial motion allows for the avoidance of unwanted resonances in the horizontal and vertical transverse planes, while still providing periodic locations at which ionization cooling components can be implemented. Properties of the linear beam dynamics have been previously reported and good agreement exists between theory, analytic solutions, and simulations. Progress on aberration compensation in the coupled correlated optics channel is presented and discussed.
UCR, Riverside, California, USA
GWU, Washington, USA
JLab, Newport News, Virginia, USA
Muons, Inc, Illinois, USA