Many mature methods to measure the betatron function of a lattice rely on beam position monitor (BPM) data and the model of the whole machine. In this study, specific sections of the Relativistic Heavy Ion Collider (RHIC) were analyzed, taking advantage of BPMs separated by drift spaces near interaction points (IPs) and B3/B4 magnet sections of RHIC. This (local) approach would provide a alternative measure of the linear optics at specific regions which can be compared to previous (global) methods. This process utilizes the phase transfer matrix built from existing BPM data from RHIC using Linear Regression (LR) techniques. Non-AC dipole BPM data as well as AC dipole data was used to measure the linear optics. It was found that the local method yields comparable beta beat to global methods; however, it differs significantly around IP6. This study demonstrates that using LR analysis has advantages and disadvantages, and that further studies are needed to improve the method.

For the 2024 100 GeV proton run at RHIC, the new sPHENIX detector will require a maximum amount of collisions within ±10 cm of its central Interaction Point (IP), and preferably few or no collisions outside this range. To maximize the collisions within the vertex, a large crossing angle of up to 2 mrad will be used, operating the Large Piwinski Angle (LPA) scheme. To compensate for the reduction in luminosity from the large Piwinski angle, a β=50 cm lattice has been designed and supported with dynamic aperture simulations. To further compensate the luminosity reduction, injector studies have been performed to support up to a 45% increase in the injected intensity relative to the previous 100 GeV run in 2015.1

The utilization of machine learning techniques in accelerator research has yielded remarkable advancements in optimization strategies. This paper presents a pioneering study employing a machine learning algorithm, GPTune, to optimize beam intensity by adjusting parameters within the EBIS injection and extraction beam lines. Demonstrating significant enhancements, our research showcases a remarkable 22% and 70% improvements in beam intensity at two different measurement locations.

The design of the electron-ion collider (EIC) at Brookhaven National Laboratory is well underway, aiming at a peak electron-proton luminosity of 10e+34 cm^-1·sec^-1. This high luminosity, the wide center-of-mass energy range from 29 to 141 GeV (e-p) and the high level of polarization require innovative solutions to maximize the performance of the machine, which makes the EIC one of the most challenging accelerator projects to date. The complexity of the EIC will be discussed, and the project status and plans will be presented.

Electron cooling of ion beams employing RF-accelerated electron bunches was successfully used for the RHIC physics program in 2020 and 2021. Electron cooler LEReC uses a high-voltage photoemission electron gun with stringent requirements for beam current, beam quality, and stability. The electron gun has a photocathode with a high-power fiber laser, and a novel cathode production, transport, and exchange system. It has been demonstrated that the high-voltage photoemission gun can continually produce a high-current electron beam with a beam quality suitable for electron cooling. We describe the operational experience with the LEReC dc photoemission gun in RHIC and discuss the important aspects needed to achieve the required beam current, beam quality, and stability. We also present recent gun tests in which stable operation at 50 mA CW beam current was established, as well as future plans.

The Normal-Conducting Radio-Frequency (NCRF) systems for the Electron-Ion Collider Hadron Storage Ring (EIC HSR) consist of 4 unique cavity resonators. The HSR NCRF systems are composed of a 24.6 MHz capture and acceleration system, a combined 49.2 MHz and 98.4 MHz bunch splitting system, and a 197 MHz storage system for collider operations. This paper presents the preliminary design of the HSR NCRF systems. We describe the unique approach taken to optimize HSR performance while limiting the total number NCRF systems, reducing the NCRF systems contributions to the total HSR impedance while reducing operating complexity.

Many mature methods to measure the betatron function of a lattice rely on beam position monitor (BPM) data and the model of the whole machine. In this study, specific sections of the Relativistic Heavy Ion Collider (RHIC) were analyzed, taking advantage of BPMs separated by drift spaces near interaction points (IPs) and B3/B4 magnet sections of RHIC. This (local) approach would provide a alternative measure of the linear optics at specific regions which can be compared to previous (global) methods. This process utilizes the phase transfer matrix built from existing BPM data from RHIC using Linear Regression (LR) techniques. Non-AC dipole BPM data as well as AC dipole data was used to measure the linear optics. It was found that the local method yields comparable beta beat to global methods; however, it differs significantly around IP6. This study demonstrates that using LR analysis has advantages and disadvantages, and that further studies are needed to improve the method.

A new high-luminosity Electron-Ion Collider (EIC) is being developed at BNL. Beam collisions occur at IP-6, involving two rings: the Electron Storage Ring (ESR) and the Hadron Storage Ring (HSR). The vacuum system of both rings is newly developed and impedance optimization is progressing. Beam-induced heating and thermal analysis are performed for both rings to manage and control thermal distribution. The study explores collective effects across the Rapid Cycling Synchrotron (RCS), ESR, and HSR using simulated single bunch wakefields. Discussions encompass impedance analysis, collective effects and beam interactions, and the impact of ion and electron clouds on beam dynamics.

High energy colliders provide a critical tool in nuclear physics study by probing the fundamental structure and dynamics of matter. Optimizing the collider’s machine parameters is both computationally and experimentally expensive. A fast and robust optimization framework that includes both beam-beam and the detailed machine lattice will be crucial to attaining the best performance of the collider. In this paper, we report on the development of an integrated framework that includes an advanced Bayesian optimization software GPTune, a self-consistent beam-beam simulation code BeamBeam3D, and the detailed lattice model from MAD-X. Some application results to the RHIC facility optimization will also be presented.