Darren Spruce

The MAX IV imaging concept

The MAX IV Laboratory is currently the synchrotron X-ray source with the beam of highest brilliance. Four imaging beamlines are in construction or in the project phase. Their common characteristic will be the high acquisition rates of phase-enhanced images. This high data flow will be managed at the local computing cluster jointly with the Swedish National Computing Infrastructure. A common image reconstruction and analysis platform is being designed to offer reliable quantification of the multidimensional images acquired at all the imaging beamlines at MAX IV.

Effective Cycling and Ramping

The National Synchrotron Radiation Centre Solaris, Krakow, Poland has been successfully built in collaboration with several institutes and organizations. The MAX IV Laboratory, Lund, Sweden and ElettraSincrotrone, Trieste, Italy, are the most important synchrotron partners. Solaris has built, as an adaptation of MAX IV, 1.5 GeV storage ring and linear accelerator based on the same components, therefore the device server for the magnet circuit has been developed by MAX IV. Ramping was included in expert consultancy services contract won by Elettra-Sincrotrone. Solving problem with the power supplies stability and thanks to snapshots usage as steps for the ramping it was possible to ramp the beam without losing current linearly.

Status of the Solaris Control System - Collaborations and Technology

The Solaris is a synchrotron light source starting just now in Krakow, Poland. It is built with strong collaboration with other European accelerator facilities. The MAX-IV project in Lund, Sweden and Tango Community are the most important partners in the project in respect to the control system. Solaris has built a twin copy of MAX-IV 1.5GeV ring and linear accelerator based on the same components as the ones of MAX-IV. Thus, both facilities share know-how and apply similar technologies for the control system, among them the Tango CS is used for software layer. Status of the control system in Krakow as well as collaborations and technological choices impact on its success are presented in this paper. THE ACCELERATOR AND BEAMLINES The Solaris machine is 1.5GeV storage ring the same as one of the MAX-IV supplied with a linear accelerator providing electron beam up to 600MeV. Since the linac is not providing full energy beam there is need of energy ramping in the storage ring. This is a difference to MAXIV setup. The Solaris project includes also two beamlines. One is using bending magnet radiation with XAS and PEEM end-stations and the other is basing on undulator source with an UARPES end-station [1]. The accelerators and beamlines are installed except few components of PEEM beamline and two Landau cavities in the storage ring. There is on-going commissioning of the accelerator [2]. The latest result is accumulation of 20mA current in the storage ring which then has been ramped to full energy of 1.5GeV. Currently certain optimization has been done that let us by the day of writing this paper (17.10.2015) accumulate the current of 48mA. The work is in progress to do energy ramping of this much od current. For now limitation are instabilities due to the ion trapping process. There is planned upgrade shutdown starting end of November 2015 till beginning of January 2016. During this period the landau cavities will be installed as well as missing components of the PEEM beamline. Network infrastructure will be supplemented with a new core switch to enable 10GBps connections through the whole network. It is also planned to do upgrade of the Tango control system to the newest version of Tango 9.1. After the shutdown commissioning of the beamlines will proceed. It is expected that the Solaris will be ready for the first external users in second half of 2016.

Timing System at MAX IV - Status and Development

A MAX IV construction of two storage rings (SR1.5GeV and SR3GeV) and a short pulse facility (SPF) has been proceeding over last years and will be finished in the middle of 2016. In 2014, few timing procurements were successfully finalized according to the MAX IV requirements (see [1] for details) and the installation works are ongoing along with the TANGO control system integration. The design covers the timing synchronization (TIM) and acquisition, fast orbit feedback (FOFB), fast machine protection system (FMPS) and integration of MAX IV operation modes. The LINAC commissioning started in 2014 and was successful together with the first beam line (FEMTOMAX). The SR3GeV commissioning started in August 2015 and is ongoing. The SR1.5GeV is being installed and will be commissioned in 2016. MAX IV OPERATION MODES MAX IV will work in 4 different modes: • LINAC 3GeV (LIN) • LINAC 3GeV + Short Pulse Facility (SPF) • LINAC 1.5GeV + Storage Ring 1.5GeV (SR1) • LINAC 3GeV + Storage Ring 3GeV (SR3) LIN and SPF are rated for 100Hz injection whereas SR1 and SR3 for 10Hz. Each mode is synchronized to its own radio frequency (RF). LIN and SPF are driven by 39 harmonics of the LINAC master oscillator (MO) 3GHz (2998500000/39=76884615.38Hz in reality, around 77MHz). The 39 harmonic is required for a synchronization of two laser systems, one at the beginning of the LINAC, other 400m away in the short pulse facility. This implementation also keeps the same constant phase for other frequencies: 100Hz LINAC injection trigger, 1kHz laser pumping frequency etc. SR1 is locked to 100MHz (RF1) and SR3 is locked to 100MHz (RF3) but those frequencies are a bit different as the real value comes from the construction and temperature parameters of storage rings. Both rings work in the same way, each SR TIM generates a LINAC injection trigger which is locked to its RF and in constant phase to its machine clock (MC). The MC phase shift (10ns step) defines the SR bucket number. SR3 stores 176 electron buckets and its MC is equal to 568kHz, whereas SR1 stores 32 electron buckets and its MC is equal to 3.12MHz. On top of that, the synchronization to mains electricity (ME) 50Hz will be implemented, so the injection will always be applied under constant parameters of high power devices. In summary, 3 different LINAC triggers are delivered: • LIN and SPF – TRIG0 (3GHz, 77MHz, 50Hz), • SR1 – TRIG1 (100MHz, 3.12MHz, 50Hz), • SR3 – TRIG3 (100MHz, 568kHz, 50Hz). The brackets include a set of frequencies which are synchronized one other. The future timing improvement considers adding 3GHz master oscillator (MO) to TRIG1 and TRIG3 (see “MO 3GHz SYNCHRONIZATION” section for more information).