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Title: Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target

Abstract

The NT-02 neutrino target in the NuMI beamline at Fermilab is a 95 cm long target made up of segmented graphite fins. It is the longest running NuMI target, which operated with a 120 GeV proton beam with maximum power of 340 kW, and saw an integrated total proton on target of 6.1 1020. Over the last half of its life, gradual degradation of neutrino yield was observed until the target was replaced. The probable causes for the target performance degradation are attributed to radiation damage, possibly including cracking caused by reduction in thermal shock resistance, as well as potential localized oxidation in the heated region of the target. Understanding the long-termstructural response of target materials exposed to proton irradiation is critical as future proton accelerator sources are becoming increasingly more powerful. As a result, an autopsy of the target was carried out to facilitate post-irradiation examination of selected graphite fins. Advanced microstructural imaging and surface elemental analysis techniques were used to characterize the condition of the fins in an effort to identify degradation mechanisms, and the relevant findings are presented in this paper.

Authors:
 [1];  [1];  [1];  [1];  [2];  [2];  [2];  [2];  [2]
  1. Fermilab
  2. PNL, Richland
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1347122
Report Number(s):
FERMILAB-CONF-16-406-AD
1517694
DOE Contract Number:
AC02-07CH11359
Resource Type:
Conference
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS

Citation Formats

Ammigan, K., Hurh, P., Sidorov, V., Zwaska, R., Asner, D. M., Casella, Casella,A.M, Edwards, D. J., Schemer-Kohrn, A. L., and Senor, D. J. Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target. United States: N. p., 2017. Web.
Ammigan, K., Hurh, P., Sidorov, V., Zwaska, R., Asner, D. M., Casella, Casella,A.M, Edwards, D. J., Schemer-Kohrn, A. L., & Senor, D. J. Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target. United States.
Ammigan, K., Hurh, P., Sidorov, V., Zwaska, R., Asner, D. M., Casella, Casella,A.M, Edwards, D. J., Schemer-Kohrn, A. L., and Senor, D. J. Fri . "Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target". United States. doi:. https://www.osti.gov/servlets/purl/1347122.
@article{osti_1347122,
title = {Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target},
author = {Ammigan, K. and Hurh, P. and Sidorov, V. and Zwaska, R. and Asner, D. M. and Casella, Casella,A.M and Edwards, D. J. and Schemer-Kohrn, A. L. and Senor, D. J.},
abstractNote = {The NT-02 neutrino target in the NuMI beamline at Fermilab is a 95 cm long target made up of segmented graphite fins. It is the longest running NuMI target, which operated with a 120 GeV proton beam with maximum power of 340 kW, and saw an integrated total proton on target of 6.1 1020. Over the last half of its life, gradual degradation of neutrino yield was observed until the target was replaced. The probable causes for the target performance degradation are attributed to radiation damage, possibly including cracking caused by reduction in thermal shock resistance, as well as potential localized oxidation in the heated region of the target. Understanding the long-termstructural response of target materials exposed to proton irradiation is critical as future proton accelerator sources are becoming increasingly more powerful. As a result, an autopsy of the target was carried out to facilitate post-irradiation examination of selected graphite fins. Advanced microstructural imaging and surface elemental analysis techniques were used to characterize the condition of the fins in an effort to identify degradation mechanisms, and the relevant findings are presented in this paper.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}

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