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An Accelerator Research facility is a unique science and engineering challenge in that the requirements for developing a robust, optimized science facility are limited by engineering and cost limitations. Each facility is planned to achieve some science goal within a given schedule and budget and is then expected to operate for three decades. In three decades, the mechanical systems and the industrial IO to control them is not likely to change. In that same time, electronics will go through some 4 generations of change. The software that integrates the systems and provides tools for operations, automation, data analysis and machine studies will have many new standards. To help understand the process of designing and planning such a facility, we explain the specifications and requirements for the Electron Ion Collider (EIC) from both a physics and engineering perspective., Proceedings of the 5th North American Particle Accelerator Conference, NAPAC2022, Albuquerque, NM, USA

The first priority of RHIC operation in 2021 was the Au+Au collisions at 3.85 GeV/nucleon, which is the lowest energy to complete the 3-year Beam Energy Scan II physics program, with RF-based electron cooling. In addition, RHIC also operated for several other physics programs including fixed target experiments, O+O at 100 GeV/nucleon, Au+Au at 8.65 GeV/nucleon, and d+Au at 100 GeV/nucleon. This report presents the operational experience and the results from RHIC operation in 2021. With Au+Au collisions at 3.85 GeV/nucleon reported in a separate report, this paper focuses on the operation conditions for the other programs mentioned above., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

Beam Energy Scan phase II (BES-II) operation in the Relativistic Heavy Ion Collider (RHIC), aiming to explore the phase transition between quark-gluon plasma (QGP) and hadronic gas, exceeded the goal of a four-fold increase in the average luminosity over the range of five gold beam energies (9.8, 7.3, 5.75, 4.59 and 3.85 GeV/nucleon) compared to those achieved during Beam Energy Scan phase I (BES-I). We will present the achievements in BES-II together with a summary of the measures taken to improve RHIC performance in the presence of several beam dynamics effects, and details on improvements made during the operation at 3.85 GeV/nucleon in 2021., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

Python provides broad design freedom to programmers and a low barrier of entry for new software developers. These aspects have proven that unless standardized, a Python codebase will tend to diverge from a common style and architecture, becoming unmaintainable across the scope of a large controls system. Mitigating these effects requires a set of tools, standards, and procedures developed to assert boundaries on certain aspects of Python development ��� namely project organization, version management, and deployment procedures. Common tools like Git, GitLab, and virtual environments form a basis for development, with in-house utilities presenting their capabilities in a clear, developer-focused way. This paper describes the necessary constraints needed for development and deployment of large-scale Python applications, the function of the tools which comprise the development environment, and how these tools are leveraged to create simple and effective procedures to guide development., Proceedings of the 18th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2021, Shanghai, China

As part of the Beam Energy Scan (BES) physics program, RHIC operated in Fixed Target mode at various beam energies in 2020. The fixed target experiment, achieved by scraping the beam halo of the circulating beam on a gold ring inserted in the beam pipe upstream of the experimental detectors, extends the range of the center-of-mass energy for BES. The machine configuration, control of rates, and results of the fixed target experiment operation in 2020 will be presented in this report., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

Accelerator control systems generates and stores many time-series data related to the performance of an accelerator and its support systems. Many of these time series data have detectable change trends and patterns. Being able to timely detect and recognize these data change trends and patterns, analyse and predict the future data changes can provide intelligent ways to improve the controls system with proactive feedback/forward actions. With the help of advanced data mining and machine learning technology, these types of analyses become easier to produce. As machine learning technology matures with the inclusion of powerful model algorithms, data processing tools, and visualization libraries in different programming languages (e.g. Python, R, Java, etc), it becomes relatively easy for developers to learn and apply machine learning technology to online accelerator control system data. This paper explores time series data analysis and forecasting in the Relativistic Heavy Ion Collider (RHIC) control systems with the Waikato Environment for Knowledge Analysis (WEKA) system and its Java data mining APIs., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

RHIC provided Au-Au collisions at beam energies of 9.8, 7.3, 4.59 and 3.85 GeV/nucleon during the first year of the Beam Energy Scan II in 2019. The physics goals at the first two higher beam energies were achieved. At the two lower beam energies, bunched electron beam cooling has been demonstrated successfully. The accelerator performance was improved compared to when RHIC was operated at these energies in earlier years. This article will introduce the challenges to operate RHIC at low energies and the corresponding countermeasures, and review the improvement of accelerator performance during the operation in 2019., Proceedings of the North American Particle Accelerator Conference, NAPAC2019, Lansing, MI, USA

RHIC operated in fixed target mode at beam energies 4.59, 7.3, and 31.2 GeV/nucleon in 2019 as a part of the Beam Energy Scan II program. To scrape beam halo effectively at the fixed target which is 2.05 m away from the center of the STAR detectors, lattice design with relative large beta function at STAR was implemented at the two lower energies. The kickers of the base-band tune (BBQ) measurement system were engaged to dilute the beam transversely to maintain the event rate except for 31.2 GeV/nucleon. In addition, beam orbit control, tune and chromaticity adjustments were used to level the event rate. This paper will review the operational experience of RHIC in fixed target mode at various energies., Proceedings of the North American Particle Accelerator Conference, NAPAC2019, Lansing, MI, USA

This paper describes the development and use of an HTTP services architecture for building controls applications within the BNL Collider-Accelerator department. Instead of binding application services (access to live, database, and archived data, etc.) into monolithic applications using libraries written in C++ or Java, this new method moves those services onto networked processes that communicate with the core applications using the HTTP protocol and a RESTful interface. This allows applications to be built for a variety of different environments, including web browsers and mobile devices, without the need to rewrite existing library code that has been built and tested over many years. Making these HTTP services available via a reverse proxy server (NGINX) adds additional flexibility and security. This paper presents implementation details, pros and cons to this approach, and expected future directions., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

This paper describes a new web page creation system that allows web developers with limited programming experience to create interactive displays of control system data. Web pages can be created that display live control system data that updates in real-time, as well as data stored within our logging/archiving and database systems. Graphical, tabular, and textual displays are supported as well as standard interaction techniques via buttons, menus and tabs. The developer creates a web page using a custom web page builder. The builder presents a web page as a user-defined grid of tiled cells. The developer chooses the display style of each cell from a list of available cell types, then customizes its data content. Final polish can be applied using HTML and CSS. Specialized tools are available for creating mobile displays. This paper shows examples of the web pages created, and provides a summary of the experience of both the web developers and users., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

In keeping with a long tradition in the BNL Collider-Accelerator Department (C-AD) controls environment, we try to provide general and simple to use interfaces to the users of the controls. In the past we have built command line tools, Java tools, and C++ tools that allow users to easily access live and historical controls data. With more demand for access through other interfaces, we recently built a set of python and MATLAB modules to simplify access to control system data. This is possible, and made relatively easy, with the development of HTTP service interfaces to the controls*. While this paper focuses on the python and MATLAB tools built on top of the HTTP services, this work demonstrates clearly how the HTTP service paradigm frees the developer from having to work from any particular operating system or develop using any particular development tool., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

Accessing database resources from Accelerator Controls servers or applications with JDBC/ODBC and other dedicated programming interfaces have been common for many years. However, availability and performance limitations of these technologies were obvious as rich web and mobile communication technologies became more mainstream. HTTP REST services have become a more reliable and common way for easy accessibility for most types of data resources, include databases. Several commercial database REST services have become available in recent years, each with their own pros and cons. This paper presents a way for setting up a generic HTTP REST database service with technology that combines the advantages of application servers (such as Glassfish), JDBC drivers, and Java technology to make major RDBMS systems easy to access and handle data in a secure way. This allows database clients to retrieve data (user data or meta data) in standard formats such as XML or JSON., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

The repository of data for the Relativistic Heavy Ion Collider and associated pre-injector accelerators consists of well over half a petabyte of uncompressed data. By todays standard, this is not a large amount of data. However, a large fraction of that data has never been analyzed and likely contains useful information. We will describe in this paper our efforts to use machine learning techniques to pull out new information from existing data. Our focus has been to look at simple problems, such as associating basic statistics on certain data sets and doing predictive analysis on single array data. The tools we have tested include unsupervised learning using Tensorflow, multimode neural networks, hierarchical temporal memory techniques using NuPic, as well as deep learning techniques using Theano and Keras., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

In order to achieve higher instantaneous and integrated luminosities, the average Au bunch intensity in RHIC has been increased by 30% compared to the preceding Au run. This increase was accomplished by merging bunches in the RHIC injector AGS. Luminosity leveling for one of the two interaction points (IP) with collisions was realized by continuous control of the vertical beam separation. Parallel to RHIC physics operation, the electron beam commissioning of a novel cooling technique with potential application in eRHIC, Coherent electron Cooling as a proof of principle (CeCPoP), was carried out. In addition, a 56 MHz superconducting RF cavity was commissioned and made operational. In this paper we will focus on the RHIC performance during the 2016 Au-Au run., Proceedings of the North American Particle Accelerator Conf., NAPAC2016, Chicago, IL, USA

A beam energy scan of deuteron-gold collision, with center-of-mass energy at 19.6, 39, 62.4 and 200.7 GeV/n, was performed at the Relativistic Heavy Ion Collider in 2016 to study the threshold for quark-gluon plasma (QGP) production. The lattice, RF, stochastic cooling and other subsystems were in different configurations for the various energies. The operational challenges changed with every new energy. The operational experience at each energy, the operation performance, highlights and lessons of the beam energy scan are reviewed in this report., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Collisions with beams of highly asymmetric rigidities (proton-Gold and proton-Aluminum) were provided for the RHIC physics programs in 2015. Magnets were moved for the first time in RHIC prior to the run to accommodate the asymmetric beam trajectories during acceleration and at store. A special ramping scheme was designed to keep the revolution frequencies of the beams in the two rings equal. The unique operational experience of the asymmetric run will be reviewed., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Analysis of accelerator data has traditionally been done using custom tools, either developed locally or at other laboratories. The actual data repositories are openly available to all users, but it can take significant effort to mine the desired data, especially as the volume of these repositories increases to hundreds of terabytes or more. Much of the data analysis is done in real time when the data is being logged. However, sometimes users wish to apply improved algorithms, look for data correlations, or perform more sophisticated analysis. There is a wide spectrum of desired analytics for this small percentage of the problem domains. In order to address this tools have been built that allow users to efficiently pull data out of the repositories but it is then left up to them to post process that data. In recent years, the use of tools to bridge standard analysis systems, such as Matlab, R, or SciPy, to the controls data repositories, has been investigated. In this paper, the tools used to extract data from the repositories, tools used to bridge the repositories to standard analysis systems, and directions being considered for the future, will be discussed., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

The first part of RHIC Run 15 consisted of nine 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 this run. The largest effort consisted of commissioning of the electron lenses, one in each ring, which are designed to compensate one of the two beam-beam interactions experienced by the proton bunches. The e-lenses therefore 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 functioning 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 capture 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., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

Applications used for Collider-Accelerator Controls at Brookhaven National Laboratory typically run as console level programs on a Linux operating system. One essential requirement for accelerator controls applications is bidirectional synchronized IO data communication. Several new web frameworks (Vaadin, GXT, node.js, etc.) have made it possible to develop web based Accelerator Controls applications that provide all the features of console based UI applications that includes bidirectional IO. Web based applications give users flexibility by providing an architecture independent domain for running applications. Security is established by restricting access to users within the local network while not limiting this access strictly to Linux consoles. Additionally, the web framework provides the opportunity to develop mobile device applications that makes it convenient for users to access information while away from the office. This paper explores the feasibility of using the Vaadin web framework for developing UI applications for Collider-Accelerator controls at Brookhaven National Laboratory., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

The spin physics program in Relativistic Heavy Ion Collider (RHIC) requires fast polarimeter to monitor the polarization evolution on the ramp and during stores. Over past decade, the polarimeter has evolved greatly to improve its performance. These include dual chamber design, monitoring camera, Si detector selection (and orientation), target quality control, and target frame modification. The preamp boards have been modified to deal with the high rate problem, too. The ultra thin carbon target lifetime is a concern. Simulations have been carried out on the target interaction with beam. Modification has also been done on the frame design. Extra caution has been put on RF shielding to deal with the pickup noises from the nearby stochastic cooling kickers. This paper summarizes the recent operation performance of this delicate device., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

Since 2012 gold and all other ions for the RHIC injector chain have been provided by an Electron Beam Ion Source (EBIS). The source is followed by an RFQ, a short Linac, and a 30 m transport line. These components replace the Tandem van de Graaff and associated 840 m transfer line. They provide ions at 2 MeV per nucleon (kinetic energy) for injection into the AGS Booster. The setup and operation of Booster and AGS with various ions from the new source are reviewed., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

As the last missing step in phase 1 of the beam energy scan (BES-I), aimed at the search for the critical point in the QCD phase diagram, RHIC collided gold ions at a beam energy of 7.3 GeV/nucleon during the FY 2014 run. While this particular energy is close to the nominal RHIC injection energy of 9.8 GeV/nucleon, it is nevertheless challenging because it happens to be close to the AGS transition energy, which makes longitudinal beam dynamics during transfer from the AGS to RHIC difficult. We report on machine performance, obstacles and solutions during the FY 2014 low energy run., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The RHIC beam lifetime in polarized proton operation is dominated by the beam-beam effect, parameter modulations, and nonlinear magnet errors in the interaction region magnets. Sextupole and skew sextupole errors have been corrected deterministically for a number of years based on tune shift measurements with orbit bumps in the triplets. During the most recent polarized proton run 10- and 12-pole correctors were set through an iterative procedure, and used for the first time operationally in one of the beams. We report on the procedure to set these high-order multipole correctors and estimate their effect on the integrated luminosity., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The Relativistic Heavy Ion Collider (RHIC) has two main operating modes with heavy ions and polarized protons respectively. In addition to a continuous increase in the bunch intensity in all modes, two major new systems were completed recently mitigating the main luminosity limit and leading to significant performance improvements. For heavy ion operation stochastic cooling mitigates the effects of intrabeam scattering, and for polarized proton operation head-on beam-beam compensation mitigated the beam-beam effect. We present the performance increases with these upgrades for heavy ions and polarized protons, as well as an overview of all operating modes past and planned., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

After running uranium-uranium and copper-gold collisions in 2012, the high energy heavy ion run of the Relativistic Heavy Ion Collider (RHIC) for Fiscal Year 14 (Run14) is back to gold-gold (Au-Au) collisions at 100 GeV/nucleon. Following the level of performance achieved in Run12, RHIC is still looking to push both instantaneous and integrated luminosity goals. To that end, a new 56 MHz superconducting RF cavity was installed and commissioned, designed to keep ions in one RF bucket and improve luminosity by allowing a smaller beta function at the interaction point (IP) due to a reduced hourglass effect. The following presents an overview of these changes and reviews the performance of the collider., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany