| Paper | Title | Other Keywords | Page |
|---|---|---|---|
| MOPWA019 | Status of the Robinson Wiggler Project at the Metrology Light Source | dipole, radiation, dynamic-aperture, damping | 132 |
|
|||
|
The beam lifetime in electron storage rings concerns machines running in decay mode as well as machines doing top-up. A standard procedure to increase the lifetime is via bunch lengthening as the lifetime depends on the electron density in the bunch. Bunch lengthening is typically achieved with higher harmonic (Landau) cavities. As noted in *, there are several advantages in using a different approach: it is possible to increase the bunch length by installing a Transverse Gradient (Robinson) Wiggler, which allows to transfer damping between the horizontal and the longitudinal plane. While increasing the bunch length, the horizontal emittance is being reduced yielding advantages regarding the source size depending on the magnet optics. At the Metrology Light Source, a primary source standard used by Germanys national metrology institute (Physikalisch-Technische Bundesanstalt)**, such a scheme is being investigated. The current state of the project including dynamic aperture effects and synchrotron radiation issues of the device is being presented in the following.
* T. Goetsch et al.,WEPRO028 in Proceedings of IPAC2014, Dresden (Germany), 2014 ** R. Klein et al., Phys. Rev. ST-AB 11, 110701, 2008 |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWA019 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPJE003 | Measuring Duke Storage Ring Lattice Using Tune Based Technique | storage-ring, quadrupole, lattice, electron | 293 |
|
|||
|
Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. The Duke electron storage ring is a dedicated driver for oscillator Free-Electron Lasers (FELs). A 34 m long straight section of the storage ring is used to host up to four FEL wigglers in several different configurations. A total of six wigglers, two planar OK-4 wigglers and four helical OK-5 wigglers, are available for FEL research. The storage ring magnetic lattice has to be designed with great flexibility to enable the storage ring operation with different FEL wigglers, at various wiggler settings, and for different electron beam energies. Since 2012, the storage ring has demonstrated all designed characteristics in terms of lattice flexibility and tuning. This work is aimed at gaining better understanding of the real storage ring lattice by performing a series of measurements of the beta-functions along the storage ring. Unlike the LOCO technique, the beta-functions in the quadrupoles are directly measured with good accuracy using a tune meassurement system. We will describe our experimental design and techniques, and measurement procedures. We will also report our preliminary results for the lattice characterization. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPJE003 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPJE067 | Applications of PLACET2 to the CTF3 Combiner Ring | dipole, simulation, quadrupole, optics | 462 |
|
|||
| The CTF3 Combiner Ring (CR) is an isochronous ring that employs RF-injection to combine multiple bunch trains (up to five) into a single one with higher bunch frequency. The length of the CR plays a critical role in obtaining the correct structure of the recombined train. PLACET2: the new recirculating version of the code PLACET is particularly suited to simulate the operational scenario. In order to validate this code, three different case studies have been considered: ring-length variations due to energy detuning, fast-beam decoherence due to uncorrected chromatic effects and vertical instabilities due to bunch-to-bunch wakefield effects. The first two effects have been measured during the last run and the predictions have been validated. The instability has been compared with previous studies. The results are presented and discussed. | |||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPJE067 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPMA053 | Characterizing Betatron Tune Knobs on Duke Storage Ring | lattice, storage-ring, operation, betatron | 672 |
|
|||
|
Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. The Duke electron storage ring is a dedicated driver for oscillator Free-Electron Lasers (FELs). A 34-m long straight section of the storage ring can host up to four FEL wigglers in several different configurations. The storage ring magnetic lattice has designed with great flexibility to enable the operation with different wiggler configurations and at different electron beam energies. To realize smooth storage ring operation with various electron beam and wiggler parameters, a sophisticated lattice feedforward compensation scheme and a set of betatron tune knobs have been designed, developed and implemented in the controls system. The built-in compensation and tune knobs have demonstrated to be highly useful to allow transparent operation of the storage ring. To fully understand the effectiveness of the lattice tuning scheme, experiments have been carried to characterize the betatron tune knobs. In this paper, we will outline the measurement techniques and procedures, report experimental results, and make important observations on the usefulness of developing an advanced light source storage ring using accurate knowledge of individual magnets with high-quality measured fields. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMA053 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPMA054 | Start-to-end Simulation of Free-electron Lasers | FEL, simulation, linac, electron | 675 |
|
|||
| Start-to-end (S2E) modeling of free-electron lasers (FELs) normally requires the use of multiple codes to correctly capture the physics in each region of the machine. Codes such as PARMELA, IMPACT-T or MICHELLE, for instance, may be used to simulate the injector. From there the linac and transport line may be handled by codes such as DIMAD, ELEGANT or IMPACT-Z. Finally, at the FEL a wiggler interaction code such as GENESIS, GINGER, or MINERVA must be used. These codes may be optimized to work with a wide range in magnitude of macro-particle numbers (from 104-108 in different codes) and have different input formats. It is therefore necessary to have translator codes to provide a bridge between each section. It is essential that these translators be able to preserve the statistical properties of the bunch while raising or lowering the number of macro-particles used between codes. In this work we show a suite of such translators designed to facilitate S2E simulations of an FEL with a new wiggler code, MINERVA, and use these codes to provide benchmarking of MINERVA against other common wiggler simulation codes. | |||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMA054 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPMN025 | Local Impedance Estimation of NSLS-II Storage Ring with Bumped Orbit | impedance, closed-orbit, damping, vacuum | 754 |
|
|||
|
Funding: DOE contract No: DE-AC02- 98CH10886 As the newly constructed 3rd generation light source, NSLS-II is expected to provide the synchrotron radiation of ultra high brightness and flux with advanced insertion devices. To minimize the beam emittance, damping wigglers are used and the small aperture is located at the straight section with the damping wiggler and the corresponding vacuum camber is NEG coated. We used the local bump method to find the effect on the beam from the narrow aperture and the paper shows the results. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMN025 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| MOPWI022 | Experimental Study of a Two-Color Storage Ring FEL | FEL, operation, storage-ring, electron | 1198 |
|
|||
|
Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. Multi-color Free-electron Lasers (FELs) have been developed on linac based FELs over the past two decades. On the storage ring, the optical klystron (OK) FEL in its early days was demonstrated to produce lasing at two adjacent wavelengths with their spectral separation limited by the bandwidth of single wiggler radiation. Here, we report a systematic experimental study on the two-color operation at the Duke FEL facility, the first experimental demonstration of a tunable two-color harmonic FEL operation of a storage ring based FEL. We demonstrate a simultaneous generation of two FEL wavelengths, one in infrared (IR) and the other in ultraviolet (UV) with a harmonic relationship. The experimental results show a good performance of the two-color FEL operation in terms of two-color wavelength tunability, power tunability and power stability. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWI022 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPWA051 | Elettra Status and Future Prospects | emittance, operation, insertion, insertion-device | 1529 |
|
|||
| The operational status of the Italian 2.4/2.0 GeV third generation light source Elettra is presented together with possible future upgrades and a vision to its future. | |||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA051 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPJE034 | A Preliminary Report from Louisiana State University CAMD Storage Ring Operating with an 11-pole 7.5 T Wiggler | operation, storage-ring, electron, injection | 1682 |
|
|||
|
Funding: Funded by the National Science Foundation. Louisiana State University installed a 7.5 T superconducting wiggler in May 2013 on the electron storage ring located at the Bennett Johnson, Sr. Center for Advanced Microstructures and Devices (CAMD). The wiggler’s influence on betatron tunes and functions, orbit, lifetime, performance, and other relevant beam parameters are described. We further comment on device operations and modifications to ring operations that were necessary to provide light for both wiggler and dipole stations. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPJE034 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPMA012 | Developing an Improved Pulsed Mode Operation for Duke Storage Ring Based FEL | FEL, operation, storage-ring, damping | 1860 |
|
|||
|
Funding: This work is supported in part by the US DoE grant # DE-FG02-97ER41033 The Duke FEL and High Intensity Gamma-ray Source (HIGS) facility is operated with an e-beam from 0.24 to 1.2 GeV and a photon beam from 190 to 1060 nm. Currently, the energy range of the gamma-ray beam is from 1 MeV to about 100 MeV, with the maximum total gamma-ray flux about 3·1010 gammas per second around 10 MeV. The FEL is typically operated in quasi-CW mode. Some HIGS user experiments can benefit tremendously from a pulsed mode of FEL operation. For that purpose, a fast steering magnet was developed years ago to modulate the FEL gain. This FEL gain modulator decouples the e-beam from the FEL beam in the interaction region for most of time, but periodically allows a brief overlap of the electron and FEL beams. This allows us to build up a high peak power FEL pulse from a well-damped electron beam. However, the use of this gain modulator at low e-beam energies can dramatically limit e-beam current due to beam instability and poor injection. To overcome these shortcomings, we have successfully tested an RF frequency modulation technique to pulse the FEL beam. In this paper, we will describe this development, and report our preliminary results of this improved pulsed FEL operation. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPMA012 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPMA014 | Extending OK5 Wiggler Operational Limit at Duke FEL/HIGS Facility | FEL, operation, electron, controls | 1863 |
|
|||
|
Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033 Since 2007 the HIGS facility has been operated to produce both linearly and circularly polarized gamma-ray beams using two FELs, the planar OK-4 FEL and helical OK-5 FEL. Presently, with the OK-5 FEL operating at 192 nm, we can produce circularly-polarized gamma-ray beams between 1 and 100 MeV for user applications. Gamma-ray production between 80 and 100 MeV required an extension of the OK-5 wiggler operation beyond the designed current limit of 3.0 kA. In 2009, we upgraded cooling and machine protection systems to successfully extend OK-5 operation to 3.5 kA. To realize HIGS gamma-ray operation beyond 100 MeV and ultimately toward 150 MeV (the pion-threshold energy), with various limitations of the VUV mirror technology, the OK-5 wigglers will need to be operated at an even higher current, between 3.6 and 4.0 kA. In this paper we present our technical solution to further extend the operation range of the OK-5 wigglers, and report our preliminary results with high-current wiggler operation. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPMA014 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPMA016 | Light Source and Accelerator Physics Research Program at Duke University | FEL, storage-ring, operation, electron | 1866 |
|
|||
|
Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. The light source and accelerator physics research program at Duke Free-Electron Laser Laboratory (DFELL), TUNL, is focused on the development of the storage ring based free-electron lasers (FELs), and a state-of-the-art Compton gamma-ray source, the High Intensity Gamma-ray Source (HIGS) which is driven by the storage ring FEL. With a maximum total flux about 3·1010 gamma/s and a spectral flux of more than 1,000 gamma/s/eV around 10 MeV, the HIGS is the world's most intense Compton gamma-ray source. Operated in the energy range from 1 to 100 MeV, the HIGS is a premier Compton gamma-ray facility in the world for a variety of nuclear physics research programs, both fundamental and applied. In this paper, we will describe our ongoing light source development to produce gamma-ray beams in the higher energy range of 100 and 158 MeV. We will also provide a summary of our recent accelerator physics and FEL physics research activities. |
|||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPMA016 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPTY022 | Alternative Optics Design of the CLIC Damping Rings with Variable Dipole Bends and High-field Wigglers | emittance, dipole, damping, optics | 2046 |
|
|||
| The CLIC Damping Rings baseline design aims to reach an ultra-low horizontal normalised emittance of 500nm-rad at 2.86GeV, based on the combined effect of TME arc cells and high-field super-conducting damping wigglers, while keeping the ring as compact as possible. In this paper, an alternative design is described, based on TME cells with longitudinally variable bends and an optimized Nb3Sn high-field wiggler. The impact of these changes on ring optics parameters and the associated optimisation steps are detailed taking account the dominant effect of intrabeam scattering. | |||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY022 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUPTY063 | FCC-ee: Energy Calibration | polarization, storage-ring, electron, simulation | 2177 |
|
|||
| FCC-ee aims to improve on electroweak precision measurements, with goals of 100 keV on the Z mass and width, and a fraction of an MeV on the W mass. Compared to LEP, this implies a much improved knowledge of the centre-of-mass energy when operating at the Z peak and WW threshold. This contribution will describe how it is planned to achieve this, by making systematic use of resonant depolarization. A number of difficulties have been identified, due in particular to the long polarization time and amplified ground motion. However the smaller emittance and energy spread of FCC-ee with respect to LEP should help achieve a much improved performance. | |||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY063 | ||
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||