Conveners
Design of SRF Cavities and HOM Damping Schemes
- Matthias Liepe (Cornell U.)
Design of SRF Cavities and HOM Damping Schemes
- Georg Hoffstaetter (Cornell University)
Design of SRF Cavities and HOM Damping Schemes
- Jacek Sekutowicz (DESY)
Design of SRF Cavities and HOM Damping Schemes
- James Maniscalco
Dr
Wencan Xu
(bnl)
10/2/18, 11:00 AM
Oral presentation
The RF system of eRHIC e- storage ring has to satisfy wide range of scenarios of eRHIC operation. This presentation will present the considerations and design of the fundamental and high harmonic SRF cavities for the storage ring. And the HOM damping scheme for these cavities will be discussed as well.
Mr
James Mitchell
(CERN)
10/2/18, 11:30 AM
Oral presentation
The Double Quarter Wave (DQW) crab cavity will be installed as part of the High-Luminosity LHC (HL-LHC) upgrade. Proof-of-principle tests are currently on-going in CERN’s Super Proton Synchrotron (SPS). For the tests, the DQW has three on-cell coaxial HOM couplers per cavity.
Currently, due to SPS space constraints, the HOM coupler is not optimal and a re-design is necessary for HL-LHC. ...
Dr
Andranik Tsakanian
(Helmholtz-Zentrum Berlin)
10/2/18, 1:00 PM
Oral presentation
The BESSY Variable pulse length Storage Ring (VSR) project is a future upgrade of the 3rd generation BESSY II light source. The key feature of the project is the simultaneous storage of long (ca. 15 ps) and short (ca. 1.7 ps) electron bunches under “standard” user optics. This challenging goal requires installation of SRF higher harmonic cavities of the fundamental 500 MHz at two different...
Jiquan Guo
(JLAB)
10/2/18, 1:45 PM
Oral presentation
Two accelerator projects at Helmholtz-Zentrum Berlin (HZB), bERLinPro and BESSY-VSR (Variable pulse length Storage Ring) upgrade, need to design three variants of SRF cavities, 1.3GHz cavities for bERLinPro and 1.5GHz/1.75GHz cavities for BESSY-VSR. These cavities have adopted waveguide HOM dampers in their design, with a few tens of watts HOM power in each load for bERLinPro cavities and a...
James Maniscalco
10/2/18, 2:15 PM
Oral presentation
Recent research into impurity-doped niobium and Nb3Sn have pushed towards unprecedentedly high quality factors and low cryogenic power consumption for SRF accelerators. These open the way to high frequency cavities (above the 1.3 GHz standard in contemporary SRF projects such as EXFEL and LCLS-II) which could significantly decrease costs for new accelerator facilities. In this talk we provide...
Mr
Shahnam Gorgi Zadeh
(Universität Rostock)
10/3/18, 9:30 AM
Oral presentation
An $e^+e^-$ collider is foreseen in the design of future circular collider (FCC-ee) to make precise measurements of the properties of the Z, W, H bosons and the top quark ($\text{t}\bar{\text{t}}$). The two limiting cases from the SRF point of view are the Z operation which is characterized by low voltage and high beam current (1.39 A) and the $\text{t}\bar{\text{t}}$ operation which requires...
Jiquan Guo
(JLAB)
10/3/18, 10:00 AM
Oral presentation
The JLab Electron-Ion Collider (JLEIC) proposed by Jefferson Lab is a high luminosity collider consists of a few high current sub-complexes, including a 3-12 GeV electron collider ring with up to 3 A beam current, a 20-100 GeV ion collider ring of up to 1 A, and a 20-55 MeV circulation bunched electron cooler ring with up to 1.5 A. Beam induced HOM problems are prevalent in the RF systems of...
Dr
Nasrin Nasresfahani
(Beams Department, RF Group, Beams and RF Studies Section)
10/3/18, 11:00 AM
Oral presentation
Extensive beam dynamic studies conducted in the framework of LIU (LHC Injectors Upgrade) project revealed a serious intensity limitation due to HOMs of the 200 MHz travelling wave cavities (TWCS) of SPS in the frequency range of 629-630 MHz. However, finding appropriate distributed damping scheme in cavities with large number of cells (like TWCs of SPS) usually accompanied with the...
Prof.
Ursula van Rienen
(University of Rostock)
10/3/18, 11:30 AM
Oral presentation
The characterization of higher order modes in chains of superconducting cavities with couplers is a challenging task that is typically accomplished using high-performance computers in combination with dedicated software packages. During the last years, an alternative approach has been developed at the University of Rostock. It is referred to as State-Space Concatenations (SSC) and allows for...
