| Paper | Title | Page |
|---|---|---|
| MOPOR018 | Single Bunch Instability Studies at Diamond Light Source | 637 |
|
||
| Single bunch instability thresholds, the associated coherent tune shifts and the bunch lengthening have been studied at Diamond light source for nominal optics. Measurements were taken under different settings of chromaticity, radio-frequency (RF) voltage and aperture of the insertion devices (IDs). The macro-particle code sbtrack was used to evaluate the instability thresholds and bunch lengthening where different impedance contributions are taken into account such as the resistive wall impedance, a broad-band resonator model and inductive impedance for the longitudinal plane. A comparison of simulation using the developed model impedance with measurements is shown for all cases. | ||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR018 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| MOPOW055 | Injection Using a Non-linear Kicker Located in the Existing Injection Straight at Diamond Storage Ring | 840 |
|
||
|
Injection studies using a non-linear kicker for the Diamond storage ring have been carried out previously*. These studies have been recently extended to investigate whether the non-linear kicker can be located in the injection straight downstream of the septum and outside the existing dipole kicker bump. If so, injection with a non-linear kicker becomes independent of the optics used, making it suitable for use in both standard and low alpha mode. With this configuration, the existing injection scheme could also be left in place, leaving open the possibility to study both schemes in situ before potentially removing the existing dipole kickers at a later date. In order to operate with the non-linear kicker, the injected beam needs to exit the transfer line at an angle of 3mrad; this has been successfully demonstrated during machine development time. The concept and feasibility studies of this scheme are presented in this paper.
* T. Pulampong, et al., Proc. IPAC 2013, Shanghai, WEPWA065, (2013) |
||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOW055 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| TUPOR012 | THz Coherent Synchrotron Radiation from Ultra-low Alpha Operating Mode at Diamond Light Source | 1682 |
|
||
| Diamond Light Source is regularly operated in low-alpha mode to provide THz coherent synchrotron radiation (CSR) and short X-ray pulses for users. In order to maintain the wide frequency range of the coherent radiation whilst improving the signal to noise ratio, an ultra-low alpha mode has been considered to shorten the bunch length even further. In order to study this mode, the analysis of single bunch dynamics resulting from a variety of wakefield sources has been investigated using a single bunch multiparticle tracking code. These results are compared with measurements recorded using a Fourier transform infrared (FTIR) interferometer on the MIRIAM beam-line at Diamond. | ||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR012 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPOW048 | Preparations for the Double Double Bend Achromat Installation in Diamond Light Source | 2953 |
|
||
| We present the status of preparations for a major installation in the Diamond storage ring which is due to take place in 2016, namely the conversion of one cell of the ring from a double bend achromat (DBA) structure, to a double-DBA, or DDBA. We present results of measurements of the new narrow bore, high strength, quadrupoles and sextupoles, as well as the four new gradient dipoles. Fabrication of entirely new narrow-gap vacuum vessel strings, a mixture of copper and stainless steel is also described. The status of assembly of the two 7m long girders is presented, as well as other preparatory engineering, power supply, controls and high level software work. | ||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW048 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPMR001 | Online Suppression of the Sextupole Resonance Driving Terms in the Diamond Storage Ring | 3381 |
|
||
|
Suppression of the sextupole resonance driving terms (RDTs) is a widely used technique for optimising the theoretical on and off-momentum dynamic aperture for electron storage rings. Recently, this technique was applied online to the Diamond storage ring, with suppression of individual RDTs achieved via a sextupole family to RDT response matrix*. In this paper we present recent studies of the method, in which the ability to improve the lifetime and injection efficiency are investigated. An extension of the technique is investigated by combining it with the Robust Conjugate Direction Search (RCDS) optimisation algorithm**.
*J. Bengtsson, et al., Phys. Rev. ST Accel. Beams 18, 074002, (2015). **X. Huang, et al., Nucl. Instrum. Methods Phys. Res. Sect. A 726, 77, (2013). |
||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMR001 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPMR050 | Studies to Install a Multipole Wiggler by Removing a Chromatic Sextupole in the Diamond Storage Ring | 3518 |
|
||
| Investigations are underway for the possible use of an achromat to install a short multipole wiggler by removing a chromatic sextupole in cell-11 of the storage ring. The effect on emittance and energy spread are found to be small, however the impact on lifetime and injection are very significant if the chromaticity is corrected normally (globally). The MOGA genetic algorithm is used to optimize the lifetime and injection efficiency in this case. We used local mirror chromatic sextupole and other chromatic sextupole family for chromaticity correction in which case the genetic algorithm found solution that restores lifetime and injection efficiency. In this paper the results of MOGA simulations using various schemes for chromaticity correction and test results in presently operational optics will be discussed. | ||
| DOI • | reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMR050 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |