The Future Circular Collider, FCC-ee, is a proposed next generation electron-positron collider aiming to provide large luminosities at beam energies from 45.6 up to 182.5 GeV. This collider faces a major challenge to deliver the design performance in the presence of realistic lattice errors. A commissioning strategy has been developed including dedicated optics designs, efficient beam-based alignment and optics corrections based on refined optics measurements. First specifications on main magnets, corrector circuits, and instrumentation have also been investigated. A summary of all these aspects is presented in this paper.

Abstract The orbit correction system (OCS) of the Canadian Light Source (CLS) comprises of 48 sets of BERGOZ beam position monitors (BPM). Each BPM has the ability to measure the position of the beam in both the X and Y directions and can record data at a rate of 1000 times per second. Inverse Response Matrix (IRM) is utilized to determine the optimal strength of the 48 sets of orbit correctors in both the X and Y directions, in order to ensure that the beam follows its desired path. The suggestion in this study is to replace the singular value decomposition (SVD) function with a neural network algorithm, which will act as the central processing unit of the orbit correction system. The training model’s design includes three hidden layers, and within each layer, there are 96 nodes. The neural network’s outputs for regular operations in CLS exhibit a mean square error (MSE) of 10 −7 . Various difficult scenarios were created to test the OCS at 8.0 mA, using offsets in different sections of the storage ring. However, the new model was able to produce the necessary orbit correctors (OC) signals without any trouble.

The number of cells in a pi-mode standing wave (SW) accelerating structure for the Compact Linear Collider (CLIC) project is limited by mode overlap with nearby modes. The distributed coupling scheme avoids mode overlap by treating each cell as independent. Designs of cells suitable for distributed coupling with strong wakefield suppression by waveguide damping have not previously been studied. In this paper we develop a SW cell to be used in a distributed coupling structure that can satisfy the CLIC transverse wake potential limit. From the middle cell of the CLIC-G* traveling wave (TW) structure, a SW cell is designed and then adapted to perform as a cell in a distributed coupling structure. Its wake potentials in an ideal case of open boundaries are reduced to satisfy the wake potential threshold. An electric boundary is added to the model to simulate total reflection at the distribution network. A horizontal coupler cell that connects to the distribution network such that the reflected wakefields remain similar to the open boundary case is simulated. A triplet module which takes advantage of cell-to-cell coupling to reduce reflected wake potential is presented.

Machine learning has recently been applied and deployed at several light source facilities in the domain of accelerator physics. Here, an approach based on machine learning to produce a fast-executing model is introduced that predicts the polarization and energy of the radiated light produced at an insertion device. This paper demonstrates how a machine learning model can be trained on simulated data and later calibrated to a smaller, limited measured data set, a technique referred to as transfer learning. This result will enable users to efficiently determine the insertion device settings for achieving arbitrary beam characteristics.

The Canadian Light Source (CLS) synchrotron uses four fast kicker magnets to inject electrons into the storage ring from a 2.9 GeV booster ring. The injection occurs over several turns of the stored beam, which is also perturbed by the injection kickers. The resultant oscillations of the stored beam can negatively affect beamline experiments, so it is desirable to implement an injection scheme which does not disturb the stored beam. Transparent injection is desired for planned top-up operations of the CLS storage ring. Many alternative injection techniques were examined as they apply to the CLS storage ring. Pulsed multipole magnets and a non-linear kicker (NLK) are the most viable options for integration with the current ring. Non-linear kicker designs are also being considered for the proposed CLS2 and studying the NLK in the limitations of the current machine provides insight to guide the work on the new machine. Simulation with the accelerator code ELEGANT shows the viability of the non-linear kicker design as developed at BESSY, MAX IV and SOLEIL for transparent injection at the CLS.

A key feature of third-generation light sources is their small vertical opening angle, which is difficult to measure experimentally. To reconstruct the vertical phase space, one can scan the beam’s position using X-ray synchrotron radiation (XSR) and a pinhole camera and scan the vertical beam size. The XSR diagnostic beamline, operational in the wavelength region of λ = 0.05 0.15 nm, in Canadian Light Source (CLS) is qualified to measure the beam position with X-ray radiation. Vertical iterations of 100 μm were executed to the beam’s original orbit and the image position was scanned through the pinhole camera. The outcomes of this experiment are: 1) the vertical beam positions that are monitored by BPMs positioned in the Double Bend Achromat (DBA) lattice in CLS on both sides of the X-ray’s source point, 2) the X-ray image of the beam that is projected through the pinhole and converted to visible light to be captured on the CCD camera. The bumps were simulated using Matlab Middle Layer (MML) for Accelerator control systems in MATLAB to get an insight of the source point’s position in the XSR’s bending magnet.

The first Southern Hemisphere X-band Laboratory for Accelerators and Beams (X-LAB) is under construction at the University of Melbourne [1], The lab will host a CERN X-band test stand containing two 12 GHz 6 MW klystron amplifiers. By power combination through hybrid couplers and the use of pulse compressors, up to 50 MW of peak power can be sent to any of to either of the two test slots at pulse repetition rates up to 400 Hz. The test stand is dedicated to RF conditioning and testing CLIC’s high gradient accelerating structures beyond 100 MV/m [2]. It will also form the basis for developing a compact accelerator for medical applications, such as radiotherapy and compact light sources. Australian researchers working as part of a collaboration between the University of Melbourne, international univer-sities, national industries, the Australian Synchrotron -ANSTO, Canadian Light Source and the CERN believe that creating a laboratory for novel accelerator research in Australia could drive technological and medical innovation. We also gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at X-LAB, radiation fields at high-energy accelerators, and the radiation monitoring system used at X-LAB. The bunker design to achieve a dose rate less than annual dose limit of 1 mSv is also shown.

The Canadian Light Source (CLS) is a 3rd generation synchrotron that is used to produce extremely bright synchrotron light that can be used for research. The light at the CLS is produced by an electron storage ring which has an emmitance of 20 nm. A 4th generation synchrotron (CLS2) is planned which will reduce the emmitance to less than 1 nm and thus reduce the transverse beam size significantly, making it very challenging to measure. A double slit interferometer can be used to measure small transverse beamsizes, as first described by Mitsuhashi. An x-ray double slit interferometer will be designed and tested at the current CLS with the goal of using this setup at CLS2.

The Canadian Light Source (CLS), Canada’s only syn-chrotron light source, is considering a linear accelerator (LINAC) upgrade. As a result, the radio frequency (RF) structure in the downstream Energy Compression System (ECS) needs to be redesigned. In this paper, we describe the design process followed to determine the geometry of the RF structure cells and coupler.

The Canadian Light Source has been in operation since 2005 and is now looking at a design concept to upgrade to a fourth generation storage ring. A brief overview is given of a possible accelerator complex layout, including some details on the lattice design and injection system. A full energy linac is being explored as an option for top-up injection and to future proof the facility for a potential FEL upgrade.

The Canadian Light Source (CLS) synchrotron operates with four in-vacuum insertion devices, three in-vacuum undulators, and one in-vacuum wiggler. Presently, each of the devices occupies half of a straight section. The wiggler is unique in our ring as it is both in-vacuum and shares a straight section with an in-vacuum undulator. We have observed gap dependent beam instabilities in the undulator located in the straight section. To better understand the problem, the cause of the instabilities was investigated using 3D electromagnetic modelling. First, the 'trapped' RF modes (natural resonances) for this undulator chamber, their Q value, and their peak frequencies were analyzed using eigenmode simulation. Secondly, beam excitation of the eigenmodes was simulated with the Wakefield solver. Herein we present the results of this electromagnetic modelling.

Abstract—This paper reports a study on the optimal magnetic design of a compact quadrupole electromagnet for the Canadian Light Source (CLS 2.0). The nature of the design is to determine a quadrupole with low relative higher order harmonics and better field quality. The design problem was formulated as an optimization model, in which the objective function is the higher order harmonics (multipole errors) and the variable to be optimized is the material distribution on the pole. The higher order harmonics arose in the quadrupole due to truncating the ideal hyperbola at a certain point to make the pole. In this project, the arisen harmonics have been optimized both transversely and longitudinally by adjusting material on the poles in a controlled way. For optimization, finite element analysis (FEA) has been conducted. A better higher order harmonics amplitudes and field quality have been achieved through the optimization. On the basis of the optimized magnetic design, electrical and cooling calculation has been performed for the magnet.

The resolution of a conventional telescope used to image visible-light synchrotron radiation is often limited by diffraction effects. To improve resolution, the double-slit interferometer method was developed at KEK and has since become popular around the world. Based on the Van Cittert-Zernike theorem relating transverse source profile to transverse spatial coherence, the particle beam size can be inferred by recording fringe contrast as a function of interferometer slit separation. In this paper, we describe the SPEAR3 double-slit interferometer, develop a theoretical framework for the interferometer and provide experimental results. Of note the double-slit system is 'rotated' about the beam axis to map the dependence of photon beam coherence on angle.

A recent upgrade to the high power RF network of the linac at the Australian Synchrotron (AS) included a SLED Type 1 Pulse Compressor which has allowed for the operation of the 100 MeV linac using a single klystron. We explore the effects of the SLED installation on the properties of the beam extracted from the linac with a particular focus on the energy spread and bunch train profile. Additionally, the optical fibre beam loss monitor (oBLM), also recently commissioned, was employed to provide shot-by-shot feedback on loss location and intensity to investigate the change in beam losses.

In July 2016, the first X-band test facility operating with two interwoven RF pulses produced from 6 MW klystron was commissioned at CERN. Outputting up to 49 MW after pulse compression [1], the new test stand allows testing of two structures concurrently with a combined repetition rate of up to 400 Hz. Commissioning of two of the four lines has been completed and testing of high gradient accelerating structures for the Compact Linear Collider has commenced. Operations have been ongoing for more than a year, where dedicated control algorithms have been developed to conditioning the structure and to keep the pulse compressors tuned. Significant progress has been made in understanding the conditioning of two structures that are sharing an interlock and vacuum system. The higher pulse repetition rate has demonstrated a significantly reduction in the time required to condition accelerating structures.