skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Fiber Optic Based Thermometry System for Superconducting RF Cavities

Abstract

Thermometry is recognized as the best technique to identify and characterize losses in SRF cavities. The most widely used and reliable apparatus for temperature mapping at cryogenic temperatures is based on carbon resistors (RTDs). The use of this technology on multi-cell cavities is inconvenient due to the very large number of sensors required to obtain sufficient spatial resolution. Recent developments make feasible the use of multiplexible fiber optic sensors for highly distributed temperature measurements. However, sensitivity of multiplexible cryogenic temperature sensors was found extending only to 12K at best and thus was not sufficient for SRF cavity thermometry. During the course of the project the team of MicroXact, JLab and Virginia Tech developed and demonstrated the multiplexible fiber optic sensor with adequate response below 20K. The demonstrated temperature resolution is by at least a factor of 60 better than that of the best multiplexible fiber optic temperature sensors reported to date. The clear path toward at least 10times better temperature resolution is shown. The first to date temperature distribution measurements with ~2.5mm spatial resolution was done with fiber optic sensors at 2K to4K temperatures. The repeatability and accuracy of the sensors were verified only at 183K, but at this temperaturemore » both parameters significantly exceeded the state of the art. The results of this work are expected to find a wide range of applications, since the results are enabling the whole new testing capabilities, not accessible before.« less

Authors:
 [1]
  1. Microxact Inc.
Publication Date:
Research Org.:
Microxact Inc.
Sponsoring Org.:
USDOE Office of Science (SC)
Contributing Org.:
MicroXact Inc. (lead organization), JLab (partner, internally funded), Virginia Tech (subcontractor), Lake Shore Cryotronics (1st year only, partner, in-kind access to testing facilities).
OSTI Identifier:
1078125
Report Number(s):
DOE/SC0001964-1
DOE Contract Number:  
SC0001964
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Fiber optic sensing, temperature sensor, temperature mapping, cryogenic, fiber bragg grating

Citation Formats

Kochergin, Vladimir. Fiber Optic Based Thermometry System for Superconducting RF Cavities. United States: N. p., 2013. Web. doi:10.2172/1078125.
Kochergin, Vladimir. Fiber Optic Based Thermometry System for Superconducting RF Cavities. United States. https://doi.org/10.2172/1078125
Kochergin, Vladimir. 2013. "Fiber Optic Based Thermometry System for Superconducting RF Cavities". United States. https://doi.org/10.2172/1078125. https://www.osti.gov/servlets/purl/1078125.
@article{osti_1078125,
title = {Fiber Optic Based Thermometry System for Superconducting RF Cavities},
author = {Kochergin, Vladimir},
abstractNote = {Thermometry is recognized as the best technique to identify and characterize losses in SRF cavities. The most widely used and reliable apparatus for temperature mapping at cryogenic temperatures is based on carbon resistors (RTDs). The use of this technology on multi-cell cavities is inconvenient due to the very large number of sensors required to obtain sufficient spatial resolution. Recent developments make feasible the use of multiplexible fiber optic sensors for highly distributed temperature measurements. However, sensitivity of multiplexible cryogenic temperature sensors was found extending only to 12K at best and thus was not sufficient for SRF cavity thermometry. During the course of the project the team of MicroXact, JLab and Virginia Tech developed and demonstrated the multiplexible fiber optic sensor with adequate response below 20K. The demonstrated temperature resolution is by at least a factor of 60 better than that of the best multiplexible fiber optic temperature sensors reported to date. The clear path toward at least 10times better temperature resolution is shown. The first to date temperature distribution measurements with ~2.5mm spatial resolution was done with fiber optic sensors at 2K to4K temperatures. The repeatability and accuracy of the sensors were verified only at 183K, but at this temperature both parameters significantly exceeded the state of the art. The results of this work are expected to find a wide range of applications, since the results are enabling the whole new testing capabilities, not accessible before.},
doi = {10.2172/1078125},
url = {https://www.osti.gov/biblio/1078125}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon May 06 00:00:00 EDT 2013},
month = {Mon May 06 00:00:00 EDT 2013}
}