Engineering topics

Gonin, I. V.

Publications and source records attributed to Gonin, I. V..

5 records

DOE OSTI2012

Multipole Effects Study for Project X Front End Cavities

Effects of RF field asymmetry along with multipoles have been studied in Project X front end cavities. One family of half wave resonators operating at 162.5 and two of spoke resonators operating at 325 MHz have been analysed. HWR and spoke res onators unlike elliptical cavities, do not have axial symmetry, hence a quadrupole perturbation to the beam is present. The purpose of this paper is to explain the approach and the calculation method used to understand and overcome the drawbacks due to th e RF field asymmetry.

43 PARTICLE ACCELERATORS↗

DOE OSTI2012

Effects of the RF Field Asymmetry in SC Cavities of the Project X

The low-energy SCRF section of CW SC linac of Project X starts from Half Wave Resonators (HWR) having operating frequency f=162.5 MHz, optimal beta= 0.11 and will accelerate the beam from 2 MeV up to 11 MeV. The preliminary analysis of beam dy namics shows that multipole effects caused by asymmetry of RF fields in HWR cavities aren t negligible. In this paper we present the analysis of influence of multipole effects on beam dynamics and discuss the possible solutions how to compensate these eff ects.

43 PARTICLE ACCELERATORS↗

DOE OSTI2012

Multipactor Simulation in SC Elliptical Shape Cavities

Typically multipactor exists near equator region in elliptical shape superconductive cavities. If the multipactor power zone dose not coincide with operating power, it is often the cavity has to pass through it before it reaches operating leve l of field. Results of multipactor simulations for several shapes of elliptical cavity are presented. New shape, which significantly suppresses multipactor, is found.

43 PARTICLE ACCELERATORS↗

DOE OSTI2012

SSR1 HOM Analysis and Measurements

Single spoke resonators (SSR1, β=0.22) are currently under development for Project X at Fermilab. In this paper, extensive Higher Order Mode (HOM) analysis carried out on SSR1 is reported including the simulated R/Q for monopoles, dipoles , and quadrupoles. HOM measurements carried out on several spoke cavities are also reported including the harmonic response and the bead pull measurements. Comparison between the measured R/Q values and the simulated ones are presented.

43 PARTICLE ACCELERATORS↗

DOE OSTI2012

Design of SSR1 Single Spoke Resonators for PXIE

The Project X Injector Experiment (PXIE) at Fermilab contains one cryomodule of Single Spoke Resonators operating at 325 MHz with a geometrical beta of 0.2. Two prototypes have been tested successfully at high gradients in the Fermilab Vertica l Test Stand (VTS). We have welded a Stainless Steel helium vessel on the first prototype and tested it in the spoke-dedicated Test Cryostat. With excellent results in hand, an order for ten bare resonators was placed with US industry. A new design for th e helium vessel was developed for these resonators with the main goal of reducing the sensitivity of the resonator to variations of the helium pressure to meet the requirements of PXIE. A new tuner was developed despite the good results of the first proto type. The new design was inevitable due to the different behavior of the resonator in the new helium vessel. Other aspects were improved such as the maintainability of the tuner motor and piezoelectric actuators allowing their replacement from access port s on the cryomodule's vacuum vessel.

43 PARTICLE ACCELERATORS↗