Magnets
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Open Access
Abstract: At Diamond injection is performed by means a of a four kicker off-axis system, relying on a perfect timing and amplitude setting to produce a closed bump. Ageing of some of the kicker vessel components has progressively spoiled the performance of the system, causing oscillations in the stored beam. Various schemes to control these oscillations have been considered including introducing an additional compensating kicker, and installing a non-linear injection kicker. Results of simulations analysing these schemes are presented, along with measurements taken in the storage ring using an existing pinger magnet. The effects of the reduction on the quality of beam seen by beamlines is also considered.
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Jun 2019
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Magnets
Optics
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Open Access
Abstract: In order to generate space for a short, out-of-vacuum multipole wiggler for the DIAD beamline, a single sextupole was removed from one of the DBA arcs in the Diamond Storage Ring during June 2018. The removal of this sextupole presented a number of challenges to the operation of the storage ring, requiring a re-optimisation of the remaining sextupole strengths*, a change in tune-point and modification of the orbit and coupling correction schemes. In this paper we describe the implementation of these changes, and provide an assessment of the impact that the installed wiggler has made on the storage ring parameters.
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Jun 2019
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Magnets
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Open Access
Abstract: Plans for upgrade of the Diamond Light Source aim to reduce beam emittance by a factor of 20 or better. This is motivated by demand for photon flux with significantly high brightness and transverse coherence. The baseline lattice design for the Diamond-II upgrade has been recently proposed, however alternative design are under investigation to reduce the emittance even further. This paper presents a new lattice design based on implementation of bending magnets with transverse field gradient only.
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Jun 2019
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Magnets
Optics
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Open Access
Abstract: The Dual Imaging and Diffraction (DIAD) beamline X-ray source is a ten pole mini wiggler. By locating the mini wiggler in place of an existing sextupole magnet, the DIAD beamline is built at a bending magnet beamline position in Diamond. To accommodate the unusual beam trajectory, a new front end was designed for the DIAD beamline. The particular designs and specifications including an improved front end slits design, as well as the synchrotron and dipole ray tracing of the front end are presented in this paper. The development process of delivering the front end - the project challenges, approach and activities are also described along with the technical challenges.
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Dec 2018
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Electrical Engineering
Magnets
Mechanical Engineering
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Open Access
Abstract: Now that all of the original straight sections in the Diamond storage ring are occupied, novel ways of converting bending magnet beamline locations into insertion device beamlines have been considered. Recently one cell of the 24 cells was reconfigured in to a Double-Double Bend Achromat (DDBA) to provide a new location for an Undulator and enable a formerly designated bending magnet beamline to become an Insertion Device Beamline*. Extending this concept for the new Dual Imaging and Diffraction (DIAD) Beamline proved to have a strong impact on lifetime and injection efficiency, so instead it was decided to remove a Sextupole magnet in one cell and substitute it with a short fixed gap Wiggler. The accelerator physics, mechanical and electrical design aspects associated with the change are described.
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Dec 2018
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Magnets
Optics
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Open Access
Abstract: The Diamond storage ring has recently been modified by replacing one of the original double bend achromat (DBA) cells with a double-DBA (DDBA) cell. The new cell marks a fundamental break to the machine symmetry, and the final engineered solution shares many design features in common with modern multi-bend achromat cells. In this paper we review the impact that the modification has had on the linear and nonlinear optics, collective effects, and overall performance. Where appropriate, comparison to model predictions are also made.
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Jun 2018
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Accelerator Physics
Insertion Devices
Magnets
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Open Access
Abstract: At Diamond Light Source we are considering an upgrade of the machine aimed at significantly reduced emittance (la factor 20), that follows a worldwide trend in similar synchrotron radiation sources. An important aspect in the design of the upgrade is the optimization of the photon beam properties, such as flux, brilliance, spot size, divergence or coherence of the new sources and how these are translated into requirements on the electron beam and on the machine design. We present a study based on a combination of accelerator physics tracking codes (AT, elegant) and of radiation codes (SPECTRA, SRW, SHADOW), with the aim at bridging the gap between machine and beamlines.
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Jun 2018
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Magnets
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Open Access
Abstract: Generalized MBA (Multi-Bend-Achromat) Chasman-Green type lattices, with a low-dispersion mid-straight, have been studied and refined by pursuing a generalized Higher Order Achromat to control the non-linear dynamics to obtain a robust design. New candidate lattice have been produced aiming for a horizontal emittance of 150 pm×rad for off-axis injection and 75 pm×rad for on-axis, the latter making use of reverse bends. The results of these studies and evaluations have been summarized in this paper.
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Jun 2018
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Controls
Magnets
Optics
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Open Access
Abstract: MAX-IV has introduced a paradigm shift in the design philosophy for the "Engineering-Science" in the quest for a diffraction limited Synchrotron Light Source. Similarly, SLS-2 has introduced a systematic method for controlling the Linear Optics beyond some 20 years of TME inspired paper designs; by introducing Reverse Bends to disentangle dispersion and focusing, which enables Longitudinal Gradient Bends to efficiently reduce the emittance. Similarly, we outline a systematic approach for how to control the Nonlinear Dynamics for these systems, by a method that was pioneered for the conceptual design of the Swiss Light Source in the mid-1990s; subsequently benchmarked and validated by the commissioning.
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Jun 2018
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Diagnostics
Magnets
Mechanical Engineering
Optics
Vacuum
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R.
Bartolini
,
C.
Abraham
,
M.
Apollonio
,
C. P.
Bailey
,
M. P.
Cox
,
A.
Day
,
R. T.
Fielder
,
N. P.
Hammond
,
M. T.
Heron
,
R.
Holdsworth
,
J.
Kay
,
I. P. S.
Martin
,
S.
Mhaskar
,
A.
Miller
,
T.
Pulampong
,
G.
Rehm
,
E. C. M.
Rial
,
A.
Rose
,
A.
Shahveh
,
B.
Singh
,
A.
Thomson
,
R. P.
Walker
Open Access
Abstract: Diamond has recently successfully commissioned a major change in the lattice consisting of the substitution of a standard double-bend achromat (DBA) cell with a modified four-bend achromat (4BA) cell called “double-double bend achromat” (DDBA). This work stems from the original studies initiated in 2012 towards a Diamond upgrade and provides the benefit of an additional straight section in the ring available for insertion devices. This paper reviews the DDBA design and layout, the implications for technical subsystems, the associated engineering challenges and the main results of the commissioning completed in April 2017.
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May 2018
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