Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userRF field-attenuation formulae for the multilayer coating model
317
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Formulae that describe the RF electromagnetic field attenuation for the multilayer coating model with a single superconductor layer and a single insulator layer deposited on a bulk superconductor are derived from a rigorous calculation with the Maxwell equations and the London equation.
rate research
Read More
The vortex penetration field of the multilayer coating model with a single superconductor layer and a single insulator layer formed on a bulk superconductor are derived. The same formula can be applied to a model with a superconductor layer formed on a bulk superconductor without an insulator layer.
The recent theoretical study on the multilayer-coating model published in Applied Physics Letters [1] is reviewed. Magnetic-field attenuation behavior in a multilayer coating model is different from a semi-infinite superconductor and a superconducting thin film. This difference causes that of the vortex-penetration field at which the Bean-Livingston surface barrier disappears. A material with smaller penetration depth, such as a pure Nb, is preferable as the substrate for pushing up the vortex-penetration field of the superconductor layer. The field limit of the whole structure of the multilayer coating model is limited not only by the vortex-penetration field of the superconductor layer, but also by that of the substrate. Appropriate thicknesses of superconductor and insulator layers can be extracted from contour plots of the field limit of the multilayer coating model given in Ref.[1].
A comment to the authors SRF Conference pre-print [1] was submitted by A. Gurevich to the arXiv [2]. In this response, we show that the arguments used in the comment are not valid. [1] arXiv:1309.3239 [2] arXiv:1309.5626
It has been observed cite{break} that breakdown in an 805 MHz pill-box cavi ty occurs at much lower gradients as an external axial magnetic field is inc reased. This effect was not observed with on open iris cavity. It is propose d that this effect depends on the relative angles of the magnetic and maximu m electric fields: parallel in the pill-box case; at an angle in the open ir is case. If so, using an open iris structure with solenoid coils in the iris es should perform even better. A lattice, using this principle, is presented, for use in 6D cooling for a Muon Collider. Experimental layouts to test th is principle are proposed.
The Electron Multipacting (EM) phenomenon is a limiting factor for the achievement of high luminosity in accelerators for positively charged particles and for the performance of RF devices. At CERN, the Super Proton Synchrotron (SPS) must be upgraded in order to feed the Large Hadron Collider (LHC) with 25 ns bunch spaced beams. At such small bunch spacing, EM may limit the performance of the SPS and consequently that of the LHC. To mitigate this phenomenon CERN is developing a carbon thin film coating with low Secondary Electron Yield (SEY) to coat the internal walls of the SPS dipoles beam pipes. This paper presents the progresses in the coating technology, the performance of the carbon coatings and the strategy for a large scale production.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
