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In this contribution we provide a summary of the LHC hardware commissioning campaign following the second CERN Long Shutdown (LS2), initially targeting the nominal LHC energy of 7 TeV. A summary of the test procedures and tools used for testing the LHC superconducting circuits is given, together with statistics on the successful test execution. The paper then focuses on the experience and observations during the main dipole training campaign, describing the encountered problems, the related analysis and mitigation measures, ultimately leading to the decision to reduce the energy target to 6.8 TeV. The re-commissioning of two powering sectors, following the identified problems, is discussed in detail. The paper concludes with an outlook to the future hardware commissioning campaigns, discussing the lessons learnt and possible strategies moving forward., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

The start of the Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) facility at CERN in 2016 came with the need for a continuous image acquisition system. The international scientific collaboration responsible for this project requested low and high resolution acquisition at a capture rate of 10Hz and 1 Hz respectively. To match these requirements, GigE digital cameras were connected to a PXI system running PharLap, a real-time operating system, using dual port 1GB/s network cards. With new requirements for a faster acquisition with higher resolution, it was decided to add 10GB/s network cards and a Network Attached Storage (NAS) directly connected to the PXI system to avoid saturating the network. There was also a request to acquire high-resolution images on several cameras during a limited duration, typically 30 seconds, in a burst acquisition mode. To comply with these new requirements PharLap had to be abandoned and replaced with Linux RT. This paper describes the limitation of the PharLap system and the lessons learned during the transition to Linux RT. We will show the improvement of CPU stability and data throughput reached., Proceedings of the 18th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2021, Shanghai, China

The LINAC4 is now equipped with two laser profile and emittance meters, basically non destructive and not limited by beam power density. A pulsed laser is transported through fibres and focused into the 160 MeV H⁻ beam. Its interaction with the H⁻ ions detaches electrons that are collected by an electron-multiplier, while the resultingH⁰ particles, after being separated from the main H⁻ beam by a dipole magnet, are recorded by a diamond strip detector, few meters away from the interaction point. The emittance and profile are reconstructed from the laser step by step scan of the beam. After several years of feasibility tests and prototyping, this paper will present all details about the final HW and SW implementation and the 2022 experimental results., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

Successful integration of industrial equipment in the CERN accelerator complex relies mainly on 3 key components. The first part is the Controls Middleware (CMW). That provides a common communication infrastructure for the accelerator controls at CERN. The second part is timing. To orchestrate and align electronic and electrical equipment across the 27 km Large Hadron Collider (LHC) at sub nanosecond precision, an elaborate timing scheme is needed. Every component has to be configured and aligned within milliseconds and then trigger in perfect harmony with each other. The third and last bit is configuration management. The COTS devices have to be kept up to date, remotely managed and compatible with each other at all times. This is done through a combination of networked Pre eXecution Environments (PXE) mounting network accessible storage on the front ends, where operating systems and packages can be maintained across systems. In this article we demonstrate how COTS based National Instruments PXI and cRIO systems can be integrated in the CERN accelerator domain for measurement and monitoring systems., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

For distributed data acquisition and control system, clock synchronization between devices is key. The internal CPU clock of a CompactRIO has an accuracy of 40 ppm at 25 degree Celsius, which can cause up to 3 sec of drift per day. To compensate for this drift, common practice is to use a central clock (such as NTP) to synchronize the systems. In addition, the cRIO has an onboard FPGA which has its own 40 MHz clock. This clock is not synchronized with the CPU, and will also cause time drift. For short measurements, this drift is usually negligible, but for continuous data acquisition systems, running 24/7, the accumulated error has to be compensated. This article will show how we synchronized all clocks across multiple systems used for monitoring seismic activities in the LHC underground and surface areas. It will also describe the mechanism used to cross check synchronization by using the CERN developed White Rabbit timing system., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

LabVIEW with its graphical approach is suited for engineers used to design and implement systems based on schematics and designs. Being a graphical language, it can be challenging to keep track of drivers, runtime engines, deployments and configurations since most of the tools on the market aimed towards this are implemented for textual languages. Configuration management is possible in the development environment via version control systems such as perforce, however at CERN and in the open source software development community in general, the tendency is moving towards Git. In this paper we demonstrate how the combination of automated builds, packaging, versioning and consistent deployment can further ease and speed up development, while ensure robustness and coherency across systems. We also show how an in-house built tool called "RADE Installer" synchronizes both development environments and drivers across workstations, empowering graphical development at CERN, by merging the open source toolchains with the workflow of LabVIEW. RADE installer represents definitively a solution for LabVIEW to keep track of drivers, runtime engines, deployments and configurations., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

Particle accelerators are complex machines with fast and high power absorption peaks. Power quality is a critical aspect for correct operation. External and internal disturbances can have significant repercussions causing beam losses or severe perturbations. Mastering the load and understanding how network disturbances propagate across the network is a crucial step for developing the grid model and realizing the limits of the existing installations. Despite the fact that several off-the-shelf solutions for real time data acquisition are available, an in-house FPGA based solution was developed to create a distributed measurement system. The system can measure power and power quality on demand as well as acquire raw current and voltage data on a defined trigger, similar to a distributed oscilloscope. In addition, the system allows recording many digital signals from the high voltage switchgear enabling electrical perturbations to be easily correlated with the state of the network. The result is a scalable system with fully customizable software, written specifically for this purpose. The system prototype has been in service for two years and full-scale deployment is currently ongoing., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

AMQP was originally developed for the finance community as an open way to communicate the vastly increasing over-the-counter trace, risk and clearing market data, without the need for a proprietary protocol and expensive license. In this paper, we explore the possibility to use AMQP with MQTT extensions in a cross platform, cross language environment, where the communication bus becomes an extendible framework in which simple/thin software clients can leverage the many expert libraries at CERN., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

In the ever-growing control system at CERN, there is a need for having an easy to use, yet fast and flexible tool that interfaces with all the different middleware in the accelerator, experiments and technical infrastructures. With RADAR 2.0 we wanted to address this issue, making a LabVIEW based, drag and drop visual tool that hides much of the system complexity from the user and within seconds gives the operator a ready to use, fully functional control system GUI. RADAR 2.0 interfaces with the CERN Middleware (CMW), the CERN Accelerator and Logging system (CALS), OPC-UA and DIM. With its class based implementation it can easily be extended to other data sources (Files, Databases, middleware) on demand., Proceedings of the 16th Int. Conf. on Accelerator and Large Experimental Control Systems, ICALEPCS2017, Barcelona, Spain

Crystal collimation is a technique that relies on highly pure bent crystals to coherently deflect beam particles - through the channeling mechanisms - onto dedicated absorbers. Standard multi-stage collimation systems for hadron beams use amorphous materials as primary collimators and might be limited by nuclear interactions and ion fragmentation that are strongly suppressed in crystals. A crystal collimation setup was installed in the betatron cleaning insertion of the Large Hadron Collider (LHC) to demonstrate with LHC beams the feasibility of this concept and to compare its performance with that of the present system. Channeling was observed for the first time with 6.5 TeV beam and and plans for further crystal collimation beam tests at the LHC are discussed. Results of these first beam tests are presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Application logging and system diagnostics is nothing new. Ever since we had the first computers scientist and engineers have been storing information about their systems, making it easier to understand what is going on and, in case of failures, what went wrong. Unfortunately there are as many different standards as there are file formats, storage types, locations, operating systems, etc. Recent development in web technology and storage has made it much simpler to gather all the different information in one place and dynamically adapt the display. With the introduction of Logstash with Elasticsearch as a backend, we store, index and query data, making it possible to display and manipulate data in whatever form one wishes. With Kibana as a generic and modern web interface on top, the information can be adapted at will. In this paper we will show how we can process almost any type of structured or unstructured data source. We will also show how data can be visualised and customised on a per user basis and how the system scales when the data volume grows., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

To shorten the development time of supervision applications, CERN has developed the UNICOS framework, which simplifies the configuration of the front-end devices and the supervision (SCADA) layer. At CERN the SCADA system of choice is WinCC OA, but for specific projects (small size, not connected to accelerator operation or not located at CERN) a more customisable SCADA using LabVIEW is an attractive alternative. Therefore a similar system, called UNICOS in LabVIEW (UiL), has been implemented. It provides a set of highly customisable re-usable components, devices and utilities. Because LabVIEW uses different programming methods than WinCC OA, the tools for automatic instantiation of devices on both the front-end and supervision layer had to be re-developed, but the configuration files of the devices and the SCADA can be reused. This paper reports how the implementation was done, it describes the first project implemented in UiL and an outlook to other possible applications., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

With the wide-spread use of asynchronous web communication mechanisms like WebSockets and WebRTC, it has now become possible to distribute industrial controls data originated in field devices or SCADA software in a scalable and event-based manner to a large number of web clients in the form of rich interactive visualizations. There is however no simple, secure and performant way yet to query large amounts of aggregated historical data. This paper presents an implementation of a tool, able to make massive quantities of pre-indexed historical data stored in ElasticSearch available to a large amount of web-based consumers through asynchronous web protocols. It also presents a simple, Opensocial-based dashboard architecture, that allows users to configure and organize rich data visualizations (based on Highcharts Javascript libraries) and create navigation flows in a responsive mobile-friendly user interface. Such techniques are used at CERN to display interactive reports about the status of the LHC infrastructure (e.g. vacuum or cryogenics installations) and give access to fine-grained historical data stored in the LHC Logging database in a matter of seconds., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia

Given the time critical applications, the use of PXI and cRIO platforms in the accelerator complex at CERN, require the integration into the CERN timing system. In this paper the present state of integration of both PXI and cRIO platforms in the present General Machine Timing system and the White Rabbit Timing system, which is its successor, is described. PXI is used for LHC collimator control and for the new generation of control systems for the kicker magnets on all CERN accelerators. The cRIO platform is being introduced for transient recording on the CERN electricity distribution system and has potential for applications in other domains, because of its real-time OS, FPGA backbone and hot swap modules. The further development intended and what type of applications are most suitable for each platform, will be discussed., Proceedings of the 15th Int. Conf. on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2015, Melbourne, Australia