Study of electron-proton beam-beam interaction in eRHIC (original) (raw)

eRHIC in Electron-Ion Operation

2019

The design effort for the electron-ion collider eRHIC has concentrated on electron-proton collisions at the highest luminosities over the widest possible energy range. The present design also provides for electron-nucleon peak luminosities of up to 4.7·10³³ cm⁻²s^{−1} with strong hadron cooling, and up to 1.7·10³³ cm⁻²s^{−1} with stochastic cooling. Here we discuss the performance limitations and design choices for electron-ion collisions that are different from the electron-proton collisions. These include the ion bunch preparation in the injector chain, acceleration and intrabeam scattering in the hadron ring, path length adjustment and synchronization with the electron ring, stochastic cooling upgrades, machine protection upgrades, and operation with polarized electron beams colliding with either unpolarized ion beams or polarized He-3.

RHIC Polarized Proton-Proton Operation at 100 GeV in Run 15

The first part of RHIC Run 15 consisted of ten weeks of polarized proton on proton collisions at a beam energy of 100 GeV at two interaction points. In this paper we discuss several of the upgrades to the collider complex that allowed for improved performance. The largest effort consisted in commissioning of the electron lenses, one in each ring, which are designed to compensate one of the two beambeam interactions experienced by the proton bunches. The e-lenses raise the per bunch intensity at which luminosity becomes beam-beam limited. A new lattice was designed to create the phase advances necessary for a beam-beam compensation with the e-lens, which also has an improved off-momentum dynamic aperture relative to previous runs. In order to take advantage of the new, higher intensity limit without suffering intensity driven emittance deterioration, other features were commissioned including a continuous transverse bunch-by-bunch damper in RHIC and a double harmonic RF cature scheme in the Booster. Other high intensity protections include improvements to the abort system and the installation of masks to intercept beam lost due to abort kicker pre-fires.

ERL based electron-ion collider eRHIC

2005

In this paper we describe eRHIC design based on the RHIC hadron rings and 10-to20 GeV energy recovery electron linac. RHIC requires a very large tunability range for c.m. energies while maintaining very high luminosity up to 1034 cm-2 s-1 per nucleon. The designs of this future polarized electron-hadron collider, eRHIC, based on a high current super-conducting energy-recovery linac (ERL) with energy of electrons up to 20 GeV, have a number of specific requirements on the ERL optics. Two of the most attractive features of this scheme are full spin transparency of the ERL at all operational energies and the capability to support up to four interaction points. We present two main layout of the eRHIC, the expected beam and luminosity parameter, and discuss the potential limitation of its performance.

eRHIC: The Electron Ion Collider at BNL and Its Spin Physics Program

AIP Conference Proceedings, 2005

We motivate the need for a future high luminosity, high energy polarized collider capable of deep inelastic scattering of polarized nucleons and nuclei. We propose that building a state of the art electron beam facility near the Relativistic Heavy Ion Collider (RHIC) complex to use one of its beams for such a facility would be the most cost effective way to achieve the physics goals. After a brief introduction to eRHIC project at BNL we present the spin physics program at eRHIC. The unpolarized e-A physics program and technical status of the collider design and detector ideas are discussed in other talks.

eRHIC-future machine for experiments on electron-ion collisions

Proceedings of …, 2006

The paper presents recent developments for the design of the high luminosity electron-ion collider, eRHIC, proposed on the basis of the existing RHIC machine. The goal of eRHIC is to provide collisions of electrons and positrons on ions and protons in the ...

High-energy high-luminosity electron-ion collider eRHIC

2011

In this paper, we describe a future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference. A new ERL accelerator, which provide 5-30 GeV electron beam, will ensure 10^33 to 10^34 cm^-2 s^-1 level luminosity.

RHIC Polarized Proton Operation for 2013

The 2013 operation of the Relativistic Heavy Ion Collider (RHIC) marks the second year of running under the RHIC II era. This year saw the implementation of several important upgrades designed to push the intensity frontier. Two new electron lenses to compensate beam-beam effects (e-lenses) have been partially installed, along with a new lattice designed for the e-lens operation. A new polarized proton source which generates about factor of 2 more intensity was commissioned as well as a host of RF upgrades ranging from a new longitudinal damper a new Landau cavity in RHIC to a new low level RF system and new beam bunching structure in AGS. We present an overview of the challenges and results from this years run.