TUOCB2
JLab, Newport News, Virginia, USA
The design strategy of an electron-ion collider for reaching high luminosities is presently based on application of strong cooling of the ion beams during collisions. In this paper, we present the main design parameters for JLEIC, a Jefferson Lab proposal of an electron-ion collider, to reach ultimate high luminosity up to 2x1034 /cm2/s.
JLab, Newport News, Virginia, USA
MIPT, Dolgoprudniy, Moscow Region, Russia
Science and Technique Laboratory Zaryad, Novosibirsk, Russia
The figure-8-shaped ion collider ring of Jefferson Lab Electron-Ion Collider (JLEIC) is transparent to the spin. It allows one to preserve proton and deuteron polarizations using weak stabilizing solenoids when accelerating the beam up to 100 GeV/c. When the stabilizing solenoids are introduced into the collider's lattice, the particle spins precess about a spin field, which consists of the field induced by the stabilizing solenoids and the zero-integer spin resonance strength. During acceleration of the beam, the induced spin field is maintained constant while the resonance strength experiences significant changes in the regions of interference peaks. The beam polarization depends on the field ramp rate of the arc magnets. Its component along the spin field is preserved if acceleration is adiabatic. We present the results of our theoretical analysis and numerical modeling of the spin dynamics during acceleration of protons and deuterons in the JLEIC ion collider ring. We demonstrate high stabil-ity of the deuteron polarization in figure-8 accelerators. We analyze a change in the beam polarization when crossing the transition energy.
SLAC, Menlo Park, California, USA
JLab, Newport News, Virginia, USA
Self Employment, Private address, USA
We present an update on the lattice design of the electron ring of the Jefferson Lab Electron-Ion Collider (JLEIC). The electron and ion collider rings feature a unique figure-8 layout providing optimal conditions for preservation of beam polarization. The rings include two arcs and two intersecting long straight sections containing a low-beta interaction region (IR) with special optics for detector polarimetry, electron beam spin rotator sections, ion beam cooling sections, and RF-cavity sections. Recent development of the electron ring lattice has been focused on minimizing the beam emittance while providing an efficient non-linear chromaticity correction and large dynamic aperture. We describe and compare three lattice designs, from which we determine the best option.
ODU, Norfolk, Virginia, USA
JLab, Newport News, Virginia, USA
ODU, Norfolk, Virginia, USA
JLab, Newport News, Virginia, USA
BNL, Upton, Long Island, New York, USA
LBNL, Berkeley, California, USA
Crab crossing scheme is essential collision scheme to achieve high luminosity for the future electron-ion collider (EIC). Since the ion beam is long when cooling is not present, the nonlinear dependence of the crabbing kick may present a challenge to the beam dynamics of the ion beam, hence a impact to the luminosity lifetime. In this paper, we present the initial result of the weak-strong and strong-strong beam-beam tracking with the crab crossing scheme. The result provides beam dynamics guidance in choosing the proper frequency the crab cavity for the future EIC.
BNL, Upton, Long Island, New York, USA
Synchrotron radiation is a potential source of background in the detector of any future electron-ion collider. In the case of the eRHIC ring-ring design, a 22mrad crossing angle eliminates the need for a separator dipole, which would otherwise be a major source of synchrotron radiation. However, electrons in the transverse tails experience strong magnetic fields in the low-beta quadrupoles near the interaction point. Despite the low electron density in the tails the resulting hard radiation generated in these strong fields is a major concern, and a set of masks needs to be in place to shield the detector from these photons. We present simulation studies and a first design of a synchrotron radiation masking scheme.
BNL, Upton, Long Island, New York, USA
The ring-ring electron-ion collider eRHIC aims at an electron-ion luminosity in the range from 1032 to 1033cm-2sec-1 over a center-of-mass energy range from 20 to 140GeV. To minimize the technical risk the design is based on existing technologies and beam parameters that have already been achieved routinely in hadron-hadron collisions at RHIC, and in electron-positron collisions elsewhere. This design has evolved considerably over the last two years, and a high level of maturity has been achieved. We will present the latest design status and give an overview of studies towards evaluating the feasibility.
BNL, Upton, Long Island, New York, USA
Requirements for the proposed BNL eRHIC Ring-Ring Electron Ion Collider (EIC) are discussed, together with the dependence of luminosity with the beam divergence and forward proton acceptance. Parameters are given for four cases. The first two use no cooling and could represent a first phase of operation. The next two use strong cooling and increased beam currents. In each case parameters are given that 1) meets the requirement for forward proton acceptance, and 2) has somewhat higher divergences giving somewhat higher luminosity.