BNL, Upton, Long Island, New York, USA
Tech-X, Boulder, Colorado, USA
We have refined the design for the Rapid Cycling Synchrotron (RCS) polarized electron injector for eRHIC. The newer design includes bypasses for the eRHIC detectors and definition of the lattice layout in the existing RHIC tunnel. Additionally, we provide more details on the RF, alignment and orbit control, and magnet specifications.
BNL, Upton, Long Island, New York, USA
Fermilab, Batavia, Illinois, USA
The electron-ion collider eRHIC aims at a luminosity around 1034cm-2sec-1, using strong cooling of the hadron beam. Since the required cooling techniques are not yet readily available, an initial version with a peak luminosity of 3*1033cm-2sec-1 is being developed that can later be outfitted with strong hadron cooling. We will report on the current design status and the envisioned path towards 1034cm-2sec-1 luminosity.
BNL, Upton, Long Island, New York, USA
RIKEN Nishina Center, Wako, Japan
Utsunomiya University, Utsunomiya, Japan
The FY18 RHIC physics program calls for Ru-Ru and Zr-Zr collisions at 100GeV using isobaric Ruthenium and Zirconium ions, each having 96 nucleons. In the injector chain, these two ions have to come from tandem and EBIS source, respectively. To reduce systematic errors in the detector, the luminosity between the two species combinations is matched as closely as possible, and the species are switched frequently. Several bunch merges are needed in the Booster and AGS to reach the desired bunch intensity for RHIC. The setup and performance of Booster and AGS with these ions are reviewed.
BNL, Upton, Long Island, New York, USA
Low Energy RHIC Electron cooler (LEReC) project is presently under commissioning at Brookhaven National Laboratory (BNL). LEReC requires high average current up to 85mA and high-quality electron beam. A 400 kV DC gun equipped with a photocathode and laser system has been chosen to provide a source of high-quality electron beams. We started testing the DC gun during the RHIC run 2017. First electron beam from LEReC DC gun was delivered in April 2017 *. During the DC gun test critical elements of LEReC such as laser beam system, cathode exchange system, cathode QE lifetime, DC gun stability, beam instrumentation, the high-power beam dump system, machine protection system and controls have been tested. Average current of 10 mA for few hours of operation was reached in August 2017. In this paper we present experimental results and experience learned during the LEReC DC gun beam testing.
* D. Kayran et al., "First Results of Commissioning DC Photo-gun for RHIC Low Energy Electron Cooler (LEReC)", in Proc of ERL2017.
BNL, Upton, Long Island, New York, USA
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
A simple, analytically correct algorithm is developed for calculating 'pencil' beam coordinates using the signals from an ideal cylindrical beam position monitor (BPM) with four pickup electrodes (PUEs) of infinitesimal widths. The algorithm is then applied to simulations of realistic BPMs with finite width PUEs. Surprisingly small deviations are found. Simple empirically determined correction terms reduce the deviations even further. Finally, the algorithm is used to study the impact of beam-size upon the precision of BPMs in the non-linear region. As an example of the data acquisition speed advantage, a FPGA-based BPM readout implementation of the new algorithm has been developed and characterized