Engineering topics

Zaplatin, Evgeny

Publications and source records attributed to Zaplatin, Evgeny.

3 records

DOE OSTI2018

Microphonics Passive Damping

Different types of external loads on the resonator walls predetermine the main working conditions of the SRF cavities. The most important of them are very high electromagnetic fields that result in strong Lorentz forces and the pressure on cavity walls from the helium tank that also deforms the cavity shape. For pulsed operation, the Lorentz forces usually play the decisive role for the cavity design. For CW operation, the liquid helium vessel pressure instability even for 2K operations is the source of large microphonics. All deformations resulting from any type of external loads on cavity walls lead to shifts in the working RF frequency in the range of hundreds of kHz. Taking into account high Q-factor of SC cavities such a large frequency shift takes the cavity out of operation. Here we present and discuss the achievements and problems of microphonics passive damping in different type SRF cavities.

43 PARTICLE ACCELERATORS↗

DOE OSTI2014

Processing and Testing of the SRF Photoinjector Cavity for BERLinPro

The BERLinPro project is a compact, c.w. SRF energy recovery linac (ERL) that is being built to develop the accelerator physics and technology required to operate the next generation of high current ERLs. The machine is designed to produce a 50 MeV 100 mA beam, with better than 1 mm-mrad emittance. The electron source for the ERL will be a SRF photoinjector equipped with a multi-alkali photocathode. In order to produce a SRF photoinjector to operate reliably at this beam current HZB has undertaken a 3 stage photoinjector development program to study the operation of SRF photoinjectors in detail. The 1.4 cell cavity being reported on here is the second stage of this development, and represents the first cavity designed by HZB for use with a high quantum efficiency multi-alkali photocathode. This paper will describe the work done to prepare the cavity for RF testing in the vertical testing dewar at Jefferson Laboratory as well as the results of these RF tests.

Burrill, Andrew↗

DOE OSTI2013

Towards a 100mA Superconducting RF Photoinjector for BERLinPro

For BERLinPro, a 100 mA CW-driven SRF energy recovery linac demonstrator facility, HZB needs to develop a photo-injector superconducting cavity which delivers a at least 1mm*mr emittance beam at high average current. To address these challenges of producing a high peak brightness beam at high repetition rate, at first HZB tested a fully superconducting injector with a lead cathode*,followed now by the design of a SC cavity allowing operation up to 4 mA using CW-modified TTF-III couplers and inserting a normal conducting high quantum efficiency cathode using the HZDR-style insert scheme. This talk will present the latest results and an overview of the measurements with the lead cathode cavity and will describe the design and optimization process, the first production results of the current design and an outlook to the further development steps towards the full power version.

Neumann, Axel↗