Bartolini, R.

Paper	Title	Page
MOPC033	Sapphire - A High Peak Brightness X-Ray Source as a Possible Option for a Next Generation UK Light Source	142
	R. P. Walker, C. Christou, J. H. Han, J. Kay Diamond, Oxfordshire R. Bartolini JAI, Oxford
	In the UK there is increasing interest in a radiation source which would provide ultra-fast (from 100 fs down to a few fs and potentially below) multi-keV X-ray pulses with high peak brightness, in order to study rapid dynamical processes in electronic and molecular systems, complementary to the newly operational Diamond Light Source which has been designed principally for high time-averaged X-ray brightness. In this paper we present the results of our initial studies for one option for a cost-effective, staged, linac based source suitable as a national facility which can act additionally as a portal to larger X-ray free-electron laser facilities in Europe, the US and Japan.
TUXM02	Performance and Trends of Storage Ring Light Sources	993
	R. Bartolini Diamond, Oxfordshire
	We present an overview of the performance of the latest generation of operating storage ring light sources. Emphasis is given to the comparison of design parameters to the achieved performances. Trends and innovations of established light sources to meet the increasing user’s demand for high brightness and different time structures will be presented. Report on upgrades and improvements will be given including orbit stability, top-up, feedback systems, lower-ID gap operation and a review of the activities for the generation of ultra-short radiation pulses in storage rings.
	Slides
TUPP020	Analysis of Collective Effects at the Diamond Storage Ring	1574
	R. Bartolini, C. Christou, R. T. Fielder, M. Jensen, A. F.D. Morgan, S. A. Pande, G. Rehm, C. A. Thomas Diamond, Oxfordshire
	The Diamond storage ring has achieved its nominal operating current of 300 mA in multi-bunch mode and up to 10 mA in single bunch mode. Several collective instabilities have been observed and their dependence on machine parameters such as chromaticities, RF voltage and fill pattern have been investigated. We report here the analysis of the observed current thresholds and rise times of the instabilities compared with analytical estimates and tracking simulations. We also present the results of the MAFIA simulations performed with the aim of understanding the main contribution to the impedance of the ring and establishing a machine impedance database.
WEPC002	Analysis of Beam Orbit Stability and Ground Vibrations at the Diamond Storage Ring	1980
	R. Bartolini, H. C. Huang, J. Kay, I. P.S. Martin Diamond, Oxfordshire
	With the aim of understanding and improving the beam orbit stability at the Diamond storage ring we launched an extensive campaign of ground and magnets vibration measurements in order to identify the sources of ground vibration and how they affect the beam orbit stability through the girder resonances. We present here the results of the measurements performed during 2007 along with a discussion of the possible remedies and the implications for the orbit feedback systems.
TUPP058	Impedance Estimation of Diamond Cavities	1673
	S. A. Pande, R. T. Fielder, M. Jensen Diamond, Oxfordshire R. Bartolini JAI, Oxford
	The RF straight section of the Diamond storage ring presently consist of two CESR type SCRF cavities with a provision to install a third cavity in the future. The cavities are equipped with HOM loads and are joined to the adjacent storage ring beam pipe using tapered transitions. The RF cavities are simulated with MAFIA, CST Studio and ABCI to estimate their contribution to the total ring impedance. We also measured the resonant frequencies and Q factors of residual HOMs in these cavities. In this paper, we present the results of our measurements and simulations which lead us to an estimation of the impedance of the RF straight.
WEPC029	Assessment of the Impact of External Stimuli on the Floor Stability of Diamond	2049
	J. Kay, H. C. Huang Diamond, Oxfordshire R. Bartolini JAI, Oxford
	Continuous vibration monitoring is carried out and the stability of the Diamond floor slab has been assessed with regard to how it has responded to various external stimuli. Data has been collected on weather conditions and comparison made at extremes with floor vibration. The impact of a high level walkway bridge on the hall floor has also been assessed and there was a unique opportunity for an operational facility to measure the vibration response during a complete power black-out. The impact of local construction work is also presented.
WEPC044	Top-Up Safety Simulations for the Diamond Storage Ring	2085
	I. P.S. Martin, C. P. Bailey, E. C. Longhi, R. P. Walker Diamond, Oxfordshire R. Bartolini, I. P.S. Martin JAI, Oxford
	To ensure that it is not possible for a train of injected electron bunches to pass down an open beam-line during top-up operation at the Diamond Light Source, an extensive program of tracking studies has been performed. Various error scenarios have been investigated, with realistic magnetic field, trajectory, aperture and energy errors all taken into account. We describe the tracking methods used, scenarios considered and the interlocks required in order to maintain user safety during top-up operation.
WEPC057	Preparation for Top-up Operation at Diamond	2121
	R. P. Walker, P. T. Bonner, F. Burge, Y. S. Chernousko, C. Christou, J. A. Dobbing, M. T. Heron, V. C. Kempson, I. P.S. Martin, G. Rehm, R. J. Rushton, S. J. Singleton, M. C. Wilson Diamond, Oxfordshire R. Bartolini JAI, Oxford
	We report on progress towards top-up operation of Diamond. We describe the extensive safety assessment that has carried out, including the measurements and simulations to assess the potential radiation doses in the case of poor injection efficiency or a top-up "accident", and the various levels of safety measures - procedures, software limits and personnel safety system interlocks - that have been implemented. We describe the top-up control algorithm, the technique used to maintain a given arbitrary filling pattern and the performance in practise. The work carried out to reduce the effect of the injection kickers on the stored beam is described, and the effect of the residual disturbance on user operation is discussed. The modifications to the timing system to provide hardware and software gating signals, and experience with the use of these, are also described.
WEPC119	First Year's Experience of Diamond Insertion Devices	2285
	E. C. Longhi, R. T. Fielder, I. P.S. Martin, J. C. Schouten, B. Singh Diamond, Oxfordshire R. Bartolini JAI, Oxford
	Diamond was commissioned at 3GeV with seven insertion devices (IDs) already installed. The phase 1 IDs include five in-vacuum permanent magnet undulators, an APPLE–2 variable polarization device, and a superconducting wiggler. Since initial commissioning of the ring, three more in-vacuum undulators have been installed, and another three devices will be installed in the coming year. In this paper, we describe commissioning, characterizing, and operating with these IDs.
THPC025	Further Advances in Understanding and Optimising Beam Dynamics in the Diamond Storage Ring	3032
	I. P.S. Martin, R. T. Fielder, E. C. Longhi, B. Singh Diamond, Oxfordshire R. Bartolini JAI, Oxford
	We report the results of recent beam dynamics studies of the Diamond storage ring. These studies were aimed at both improving our understanding of the machine operation as well as establishing a reliable, well corrected lattice with long lifetime and high injection efficiency suitable for later top-up operation. Particular attention has been given to measuring and controlling the linear optics of the lattice, to determining the various contributions to the overall beam lifetime and to optimising the sextupole strengths for good on and off momentum dynamic aperture. For each topic, detailed comparisons with model predictions are also described.
THPC053	Turn-by-turn Data Analysis at the Diamond Storage Ring	3101
	R. Bartolini, I. P.S. Martin, G. Rehm, J. Rowland Diamond, Oxfordshire
	The Diamond Storage Ring has been recently equipped with a set of two pinger magnets that can excite betatron oscillations to large amplitudes in both planes of motion. In conjunction with the turn-by-turn capabilities available at all BPMs, the system provides a powerful diagnostic tools for the characterisation of the linear and non-linear beam dynamics of the electron beam in the storage ring. We report the first results on the application of the Frequency Map Analysis and the measurement of the resonant driving terms at the Diamond Storage Ring.