arXiv subjects

S. Cheban

Publications and source records attributed to S. Cheban.

6 recordsLinked to original sources

arXiv2026

Development of Design for the STS Extraction Magnet System

The Oak Ridge National Laboratory STS Project will enhance the Spallation Neutron Source by adding a new neutron source. The upgrade includes a 30% increase in beam energy and a 50% boost in beam current, doubling the accelerator's power capability to 2.8 MW. The Ring-to-Second-Target Beam Transport (RTST) system is vital in directing high-energy proton beams to the new second target station. New magnets have to fit into a restricted space within the existing beamline to add the new extraction line. New, fast kicker magnets (Pulsed Dipole), a focusing quad with an aperture for both beamlines (Large Quad) and the replacement of existing 21Q40 Quads with 'Narrow Quads' having identical fields as the existing design are Fermilab's responsibility. The design of these magnets poses unique challenges, as in addition to the high requirements on the quality of magnetic fields, they are subject to major restrictions related to their dimensions.

physics.acc-ph↗

arXiv2023

First Results From Nanoindentation of Vapor Diffused Nb3Sn Films on Nb

The mechanical vulnerability of the Nb3Sn-coated cavities is identified as one of the significant technical hurdles toward deploying them in practical accelerator applications in the not-so-distant future. It is crucial to characterize the material's mechanical properties in ways to address such vulnerability. Nanoindentation is a widely used technique for measuring the mechanical properties of thin films that involves indenting the film with a small diamond tip and measuring the force-displacement response to calculate the film's elastic modulus, hardness, and other mechanical properties. The nanoindentation analysis was performed on multiple vapor-diffused Nb3Sn samples coated at Jefferson Lab and Fermilab coating facilities for the first time. This contribution will discuss the first results obtained from the nanoindentation of Nb3Sn-coated Nb samples prepared via the Sn vapor diffusion technique.

physics.acc-ph↗

arXiv2023

Preservation of the High Quality Factor and Accelerating Gradient of Nb3Sn-coated Cavity During Pair Assembly

Two CEBAF 5-cell accelerator cavities have been coated with Nb3Sn film using the vapor diffusion technique. One cavity was coated in the Jefferson Lab Nb3Sn cavity coating system, and the other in the Fermilab Nb3Sn coating system. Both cavities were measured at 4 K and 2 K in the vertical dewar test in each lab and then assembled into a cavity pair at Jefferson Lab. Previous attempts to assemble Nb3Sn cavities into a cavity pair degraded the superconducting properties of Nb3Sn-coated cavities. This contribution discusses the efforts to identify and mitigate the pair assembly challenges and will present the results of the vertical tests before and after pair assembly. Notably, one of the cavities reached the highest gradient above 80 mT in the vertical test after the pair assembly.

physics.acc-ph↗

arXiv2023

Design Status of BCC Cryomodule for LCLS-II HE

A Buncher or Capture Cavity (BCC) Cryomodule is currently in development at Fermilab for use in a second injector for LCLS-II-HE. The BCC Cryomodule is designed to contain one 1.3 GHz cavity and one solenoid magnet as part of a 100MeV low emittance injector. The design considerations for the Cryomodule are similar to the LCLS-II cryomodule with additional requirements to account for additional vacuum loading at the end of this vessel due to the termination of the insulating vacuum. To accomplish this design, the cryomodule is being developed using the experience gained during the development of the LCLS-II cryomodule. The design, analysis, and status of the Cryomodule will be discussed.

physics.acc-ph↗

arXiv2022

Validation of the 650 MHZ SRF tuner on the low and high beta cavities for PIP-II at 2 K*

The PIP-II linac will include thirty-six beta=0.61 and twenty-four beta=0.92 650 MHz 5 cell elliptical SRF cavities. Each cavity will be equipped with a tuning system consisting of a double lever slow tuner for coarse frequency tuning and a piezoelectric actuator for fine frequency tuning. The same tuner will be used for both the beta=0.61 and beta=0.92 cavities. Results of testing the cavity-tuner system for the beta=0.61 will be presented for the first time.

physics.acc-ph↗

arXiv2015

Mu2e Technical Design Report

The Mu2e experiment at Fermilab will search for charged lepton flavor violation via the coherent conversion process mu- N --> e- N with a sensitivity approximately four orders of magnitude better than the current world's best limits for this process. The experiment's sensitivity offers discovery potential over a wide array of new physics models and probes mass scales well beyond the reach of the LHC. We describe herein the preliminary design of the proposed Mu2e experiment. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2 approval.

physics.ins-det↗