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The Proton Power Upgrade (PPU) Project is approved for the Spallation Neutron Source at Oak Ridge National Laboratory and will double the proton beam power capability from 1.4 MW to 2.8 MW with 2 MW beam power available to the first target station. A second target station is planned and will utilize the remaining beam power in the future. The proton power increase will be supported with the addition of twenty-eight new superconducting cavities powered by 700 kW peak power klystrons to increase beam energy while increases to the beam current will be done with a combination of existing RF margin, and DTL HPRF upgrades. The original low-level RF control system has proven to be reliable over the past 15 years of operations, but obsolescence issues mandate a replacement system be developed for the PPU project. The replacement system is realized in a µTCA.4 platform using a combination of commercial off-the-shelf boards and custom hardware to support the requirements of PPU. This paper presents the prototype hardware, firmware, and software development activities along with preliminary testing results of the new system., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

We will present currents status of the CeC experiment at RHIC and discuss plans for future. Special focus will be given to unexpected experimental results obtained during RHIC Run 18 and discovery of a previously unknown type of microwave instability. We called this new phenomenon micro-bunching Plasma Cascade Instability (PCI). Our plan for future experiments includes suppressing this instability in the CeC accelerator and using it as a broad-band amplifier in the CeC system., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

In this talk we will present the status of the Coherent electron Cooling demonstration experiment at BNL and our proposed step using plasma-cascade micro-bunching amplifier. We will present both the progress and the stumbling blocks with this challenging project. The presentation will also contain relevant theory and simulations. Finally, we will present the design of our next experiment and prediction for CeC cooling 26.5 GeV/u hadron beam in RHIC., Proceedings of the 12th Workshop on Beam Cooling and Related Topics, COOL2019, Novosibirsk, Russia

The Coherent Electron Cooling (CeC) Proof-of-Principle experiment [1], installed in the RHIC tunnel at BNL, has completed its second run. In this experiment, an FEL is used to amplify patterns imprinted on the cooling electron beam by the RHIC ion bunches and then the imprinted pattern is fed back to the ions to achieve cooling of the ion beam. Diagnostics for the CeC experiment have been fully commissioned during this year’s run. An overview of the beam instrumentation is presented, this includes devices for measurements of beam current, position, profile, bunch charge, emittance, as well as gun photocathode imaging and FEL infra-red light emission diagnostics. Design details are discussed and beam measurement results are presented., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

Electron cooler with bunched electron beam is being commissioned at the Relativistic Heavy Ion Collider at BNL. For the cooler to operate the energies of the hadron and electron beams should be matched with high accuracy. We have developed time-of-flight technique based on the phase measurement of the beam induced signal in the beam position monitors separated by a drift. We present the method description and experimental results., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

Coherent electron cooling is new cooling technique to be tested at BNL. Presently we are in the commissioning stage of the accelerator system. In this paper we present status of various systems and achieved beam parameters as well as operational experience. Near term future plans are also discussed., Proceedings of the North American Particle Accelerator Conf., NAPAC2016, Chicago, IL, USA

The operating parameters for Brookhaven National Laboratory's Low Energy RHIC Electron Cooling (LEReC) project create a unique challenge. To ensure proper beam trajectories for cooling, the relative position between the electron and the ion beam needs to be known to within 50μm. In addition, time of flight needs to be provided for electron beam energy measurement. Various issues have become apparent as testing has progressed, such as mismatches in cable impedance and drifts due to temperature sensitivity. This paper will explore the difficulties related to achieving the level of accuracy required for this system, as well as the potential solutions for these problems., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

A new BPM electronics module (V301) has been developed at BNL that uses the latest System on a Chip (SoC) technologies to provide a system with better performance and lower cost per module than before. The future of RHIC ion runs will include new RF conditions as well as a wider dynamic range in intensity. Plans for the use of electron beams, both in ion cooling applications and a future electron-ion collider, have also driven this architecture toward a highly configurable approach. The RF input section has been designed such that jumpers can be changed to allow a single board to provide ion or electron optimized analog filtering. These channels are sampled with four 14-bit 400MSPS A/D converters. The SoC's ARM processor allows a Linux OS to run directly on the module along with a controls system software interface. The FPGA is used to process samples from the ADCs and perform position calculations. A suite of peripherals including dual Ethernet ports, uSD storage, and an interface to the RHIC timing system are also included. A second revision board which includes ultra-low jitter ADC clock synthesis and distribution and improved power supplies is currently being commissioned., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

The 3.8 km circumference Relativistic Heavy Ion Collider (RHIC) at BNL has been in operation since 2000. An electron-ion collider (eRHIC), which is in the design phase, plans to use one of the existing ion rings and new electron rings constructed in the existing tunnel to provide collisions of up to 21.2 GeV electrons with up to 100 GeV gold ions, 250 GeV polarized protons, as well as other species. Many new real-time systems will be required to satisfy the needs of eRHIC, including over 2000 beam position monitors, 1000 beam loss monitors, 18 current monitors, feedback systems, controls for about 10,000 power supplies, machine protection system, new beam timing systems, and more. The selected architecture must be flexible, expandable, cost-effective, reliable, and easy to maintain. Interface with existing and new accelerator timing systems is required, and compatibility with existing infrastructure and equipment must be maintained. Embedded modules based on the Xilinx Zynq gate array, with direct Ethernet connection and on-board Linux, housed in multi-slot chassis (VME, VPX, TCA, etc.) is under consideration. Preliminary design concepts for the architecture will be presented., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

High-gradient CW photo-injectors operating at high ac-celerating gradients promise to revolutionize many sci-ences and applications. They can establish the basis for super-bright monochromatic X-ray and gamma-ray sources, high luminosity hadron colliders, nuclear- waste transmutation or a new generation of microchip produc-tion. In this paper we report on our operation of a super-conducting RF electron gun with a record-high accelerat-ing gradient at the CsK2Sb photocathode (i.e. ~ 20 MV/m) generating a record-high bunch charge (i.e., 2 nC). We briefly describe the system and then detail our experimental results., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

RHIC will be run at low ion beam center-of-mass energies of 7.7 - 20 GeV/nucleon, much lower than the typical operations at 100 GeV/nucleon. The primary motivation is to explore the existence and location of the critical point on the QCD phase diagram. An electron accelerator is being constructed to provide Low Energy RHIC electron Cooling (LEReC) to cool both the blue & yellow RHIC ion beams by co-propagating a 10 - 50 mA electron beam of 1.6 - 2.6 MeV. This cooling facility will include a 400 keV DC gun, SRF booster cavity and a beam transport with multiple phase adjusting RF cavities to bring the beam to one ring to allow electron-ion co-propagation for ~21 m, then through a 180° U-turn electron transport so that the same electron beam can similarly cool the other counter-rotating ion beam, and finally to a beam dump. The injector commissioning is planned to start in early 2017 and full LEReC commissioning planned to start in early 2018. The instrumentation systems that will be described include current transformers, BPMs, profile monitors, multi-slit and single slit scanning emittance stations, time-of-flight and magnetic energy measurements, and beam halo & loss monitors., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain