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As other low emittance machine upgrades ALBA-II proposal considers operating in full coupling. In such configuration the horizontal emittance is further reduced while the lifetime is increased at the price of working close to equal fractional tunes. This mode of operation has not been adopted by any existing light source to date, and it presents a few disadvantages, like the optics degradation, injection efficiency reduction and beam size stability. In this paper the above mentioned difficulties are studied for the present ALBA storage ring in full coupling conditions., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

The polarization of the synchrotron radiation produced by a bending magnet can be selected by properly choosing the vertical emission angle. At beamlines this can be done by moving a slit to cut out unwanted polarization: this method is time consuming and not very reproducible. Another option is to fix the slit position and generate a local bump with the electron beam, and vary the emission angle at the source point such that the slit is illuminated with the desired polarization. At ALBA, we have implemented this option within the Fast Orbit Feedback, which allows to perform the angle switch in less than one minute without affecting the other beamlines. This report describes the implementation of this technique for the dipole beamline MISTRAL at the ALBA Synchrotron., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

Injection into the ALBA-II storage ring will be performed off-axis in a 4 meters straight section with a single multipole kicker. We present a novel topology for the coils of the injection kicker, named double dipole kicker (DDK). The resulting magnetic field is the superposition of two opposite dipoles, generated by four inner and four outer conductor rods. When the eight rods are powered, the dipole term cancels and the remaining multipole field is used for off-axis injection. Alternatively, when the four inner rods are switched off, an almost pure dipole is produced, that is useful for on-axis injection during the commissioning. A prototype of DDK is presently under design to be installed and tested in the existing ALBA storage ring. The positioning of the rods is calculated in order to maximise the kick efficiency in mrad/kA and minimise the disturbance to the orbit and the emittance of the stored beam. A metallic coating with optimised thickness along the inner ceramic vacuum chamber should provide compensation for the eddy currents induced field in order to minimize the disturbance to the stored beam while ensuring sufficiently low heat dissipation by the beam image currents., Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand

We propose a novel technique to measure the linear optics in storage rings based on the acquisition of the inverse orbit response matrix (iORM). The iORM consists in the orbit correctors magnets (OCM) strength changes needed to produce a local orbit variation in each beam position monitor (BPM). This measurement can be implemented by introducing sequentially small changes in the BPM offsets and logging the OCM setting variations when the orbit correction is running. Very high precision and accuracy in the OCM set-points is required which poses a considerable challenge. Since the orbit feedback (FOFB) is kept running, the iORM could potentially be acquired in parallel to users storage ring operation. Since the iORM is very linear and local, optics perturbations could be easily diagnosed online. This paper introduces the iORM measurement concept and presents the progress of these studies at ALBA, where the implementation of this technique is limited by hysteresis effects in the OCM and the FOFB performance., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The first lattice studied in 2019 for the ALBA upgrade was a 7BA lattice with two dispersion bumps, for localised chromatic correction. That lattice had limited dynamic aperture and momentum acceptance. In 2020 we started to explore a different approach to find an MBA lattice with distributed chromatic correction that meets the same emittance goal with larger dynamic aperture and momentum acceptance. The choice of the number of bendings per cell, as well as the tuning of the magnet gradients, is carried out by developing a light weight solver that performs both the emittance and chromaticity optimisation of the arcs and the matching of the linear optics in the straight sections. We present the status of the storage ring upgrade studies, the performance of the new developed lattice, together with the issues related with the injection scheme., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The orbit bump technique has been used at the ALBA Storage Ring to characterize with good precision the impedance of single machine elements, like the in-vacuum undulators or the CLIC stripline kicker. The results are compared with theoretical studies, as well as impedance measurements done at ALBA using other methods like the turn by turn betatron phase or from the analysis of the detuning slopes of the Transverse Mode Coupling Instability., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

ALBA has started a study that will produce the design of a new lattice for a diffraction limited photon source. The baseline lattice should preserve the present circumference and energy, and keep the insertion device beamline source points as much as possible unchanged. The first solution is a 16-fold periodic ring based on a 7BA cell with dispersion bump, paired sextupoles and anti-bends. An emittance of 155 pm·rad would be reached without longitudinal gradient in the dipole magnets., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The non-invasive diagnostics in the ALBA Booster-to-Storage (BTS) transfer consist of Beam Position Monitors (BPM) and Synchrotron Radiation Monitors (SRM), which together provide position, size and shape of the beam. However, they were not reliable enough for a systematic improvement of the transfer efficiency in the BTS, which has been fluctuating since day one. In order to optimize it, two major upgradse have been performed: first, the BPM electronics have been upgraded for single-pass beam detection, showing a factor 10 better position resolution than the former units. Secondly, the SRMs mechanics and automation were significantly improved to provide a more robust optics alignment. Both BPMs and SRMs are now routinely used to keep transmission efficiency along the BTS constant over weeks., Proceedings of the 6th Int. Beam Instrumentation Conf., IBIC2017, Grand Rapids, MI, USA

Injection into the ALBA storage ring presently uses a conventional local injection bump with four dipole kickers. However, following the promising results of the first tests with single multipole kicker injection at other light sources, studies to implement this new injection scheme have been started for ALBA. Two possible designs for the kicker have been considered: a pure octupole and a non-linear magnet similar to the BESSY type. A comparison between the expected performances of the two kicker designs has been carried out in terms of injection efficiency and transparency for the users. This paper summarises the beam dynamics results from multi-particle tracking simulations and the proposed kicker magnet design., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

A novel method to perform Beam Based Alignment has been tested at ALBA using the 10kHz fast acquisition BPMs together with an AC excitation of the corrector magnets allowing to speed up the beam based alignment process. The former approach relies on software synchronization and tango device servers to execute a series of DC corrector magnets and quadrupoles settings designed to avoid the quadrupole hysteresis effects. The approach that we present here is simpler, gives the same level of accuracy and precision and speeds up the measurement by a factor 10. The total measurement time has changed from 5 hours to 10 minutes., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

At ALBA the standard orbit response matrix measurement with DC corrector magnet (CM) modulation is being upgraded with an AC excitation of the correctors combined with the synchronized beam position monitor (BPM) acquisition data rate at 10 kHz. Several types of excitation waveforms (sinusoidal vs square types) and frequencies have been tested and compared to optimize the measurement precision and repeatability. The data acquisition time of the ALBA response matrix (88 horizontal and 88 vertical correctors) with the new AC method takes 1 minute to complete instead of 7 minutes of the standard technique., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The ALBA insertion device beamlines have a horizontal and vertical rms source size of 130 and 5.5 microns. Protein crystallography beamlines (Xaloc) would benefit from a reduction of the horizontal and increase of the vertical beam size, to gain spatial resolution and avoid anisotropy effects. A modified lattice with horizontal and vertical beam size of 74 and 9 microns has been setup and tested, breaking the ring symmetry, with different setting of the six neightbouring quadrupoles at each side of the Xaloc insertion device. Such configuration keeps the nominal emittance almost unvaried and the working point is recovered by small changes in the quadrupole strengths of the four symmetric matching sections. A dedicated setting of the nine available sextupole families has been obtained by numerical optimization of the dynamical apertures and tune shifts. The lattice settings have been satisfactorily tested. The measured lifetime is reduced a factor two and the injection efficiency decreases to 60%. Finally, the option of increasing the number of sextupole families, to recover the dynamic aperture and guarantee the injection efficiency, has been studied., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

A transverse impedance source manifests itself, among other ways, by producing a small defocusing kick which depends on the beam bunch charge. By repeating optics measurements for different bunch charges, it is possible to disentangle the contribution produced by each impedance source from the dominating focusing effects given by the machine optics. But hunting for such faint defocusing effects poses strong requirements on the precision and sensibility of the measurements, and slow machine drifts or different thermal conditions shall be avoided. In this report, we present a novel method to assess in a fast and precise manner machine optics for different bunch charges using BPM turn-by-turn data and hybrid filling patterns. Finally, measurements for different ALBA machine components like scrapers and In-vacuum undulators are compared with simulation results., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The N-BPM method recently developed for the LHC has significantly improved the precision of optics measurements which are based on beam position monitor (BPM) turn-by-turn data. The main improvement is owed to the consideration of correlations for statistical and systematic error sources, as well as increasing the amount of BPM combinations for one measurement. We present how this technique can be applied at light sources like ALBA, and compare the results with other methods., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

Turn-by-turn measurements paves the way for fast storage ring diagnostics. On the other hand turn-by-turn technique is by its very nature delicate, requiring an extensive system tuning and understanding. During last year several attempts to recover linear model informations from turn-by-turn measurements has been carried out in cooperation between the synchrotrons of SOLEIL and ALBA. A routine to extract phase advance and betatron amplitude from turn-by-turn measurements in presence of damping has been developed. Moreover a procedure to retrieve quadrupole errors from such observables has been developed tested and verified against the traditional diagnostics tools based on closed orbit measurements. A comparison between the different methods and the performance of the two different experimental setups are reported., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

A proposal of a low alpha lattice for the ALBA third generation light source is presented. Opposed to most of other machines, belonging to the same category, ALBA employs an optimized lattice making use of combined function dipoles. This has permitted a very compact design stripped out of all not strictly necessary quadrupoles resulting in a lack of flexibility. For such a reason the common approaches used in many other synchrotrons can not be directly applied to ALBA and a different strategy has to worked out., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

This paper summarizes the tasks carried out to develop a turn-by-turn (TBT) measurement system at ALBA. These tasks mainly include testing the MAF firmware for the libera BPMs and implementing the necessary analytical tools to infer the beam dynamics parameters. TBT measurements using an injection kicker are presented. Linear and non-linear beam dynamics results are compared with LOCO. Results are still preliminary since a good agreement with the linear model has not been achieved yet., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The ALBA light source has been operating in decay mode since May 2012. Now it is ready for top-up operation, which should become the standard operation mode for users from mid 2014. In this paper we are going to summarise the different steps that have taken place before the start of top-up operation: radiation safety simulations and measurements, upgrade of hardware and software interlocks, control software and injection optimisation., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

The synchrotron light source ALBA incorporates 6 insertion devices (2 Apple-II type undulators, 2 plannar in-vacuum undulators, 1 normal conducting multipole wiggler and 1 superconduction multipole wiggler) at the start of operation. The effect of the different IDs in the performance of the facility is evaluated, using several methods (kick maps, hard edge models, dynamic multipoles, …), including a comparison of the agreement of the different models and simulation codes. According to the results, and due mainly to the influence of the superconducting wiggler, a new working point has been selected., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The high order magnetic multipole components of all the magnets in the ALBA storage ring have been measured. Previous studies have simulated the effects of the HOMs using statistic methods. The magnets have been installed now in the tunnel, allowing for a better simulation of the future impact of the HOMs in the performance of the light source. In this paper, the effect of the high order multipoles of the dipole, quadrupole and sextupole magnets in the dynamic aperture and the Touschek lifetime are reviewed., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

The commissioning of the booster for the synchrotron light source ALBA should take place in the period December 2009-January 2010. In this paper, the beam dynamics aspects of the commissioning are described, including the studies performed, the main problems find during the commissioning and a comparison of the measured beam parameters to the design one. A description of the software tools used and developed for the task is included., Proceedings of the 1st International Particle Accelerator Conference, IPAC2010, Kyoto, Japan

A pinger magnet system consisting of two short kickers, one for each transversal plane, has been recently commissioned at the ALBA Synchrotron Light Source. The kickers can excite large betatron oscillations on the electron beam in order to probe the linear and non-linear beam dynamics regime together with the turn-by turn capabilities of the BPMs. The kickers are mounted in a single Ti coated ceramic vacuum chamber, have a length of 0.3 m each and provide a half sine pulse with a pulse length of 1 μs at an amplitude of 1.4 mrad and the pulser unit is based on solid state technology. This report summarises the steps followed from its design until its installation, electric and magnetic characterisation in the laboratory, and the first results with beam., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA