{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T20:19:42Z","timestamp":1774901982195,"version":"3.50.1"},"reference-count":25,"publisher":"AIP Publishing","issue":"12","funder":[{"DOI":"10.13039\/100019784","name":"EUROfusion","doi-asserted-by":"publisher","award":["101052200"],"award-info":[{"award-number":["101052200"]}],"id":[{"id":"10.13039\/100019784","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Swiss Secretariat for Education,Research and Innovation"}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,12,1]]},"abstract":"<jats:p>Massive material injections in the JET tokamak have been observed to substantially affect resistive bolometer measurements, resulting in a spurious radiated power signal proportional to the quantity injected and reaching up to 8\u00a0MW. These bolometers are calibrated and designed to operate in near vacuum but certain scenarios requiring large gas injections can push the neutral pressure past nominal values. This study demonstrates that the bolometry measurement can be affected at neutral pressures above 0.1\u00a0Pa following injections with standard gas valves, shattered pellet injections, and particularly massive gas injections. The power measurement of resistive bolometers is based on the temperature difference between a measurement sensor exposed to radiation and a shielded reference sensor. We employ a thermal conductivity model to demonstrate that the conduction through the gas and the distinct geometries between the sensors can affect their cooling efficiency. This additional cooling pathway, coupled with the Joule heating from the applied voltage causes the equilibrium temperatures of the sensors to diverge. Being the very basis of the measure, this temperature difference induces a signal that is erroneously interpreted as radiated power. Experiments show large discrepancies in the response to neutral pressure among bolometer channels, attributed to variations in channel physical parameters. Nonetheless, the modeled total radiated power reproduces the experimental measurements within an order of magnitude, affirming the sensitivity of resistive bolometers to neutral pressure and gas species.<\/jats:p>","DOI":"10.1063\/5.0224783","type":"journal-article","created":{"date-parts":[[2024,12,11]],"date-time":"2024-12-11T18:49:18Z","timestamp":1733942958000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":1,"title":["Spurious radiated power signal following massive material injections in JET and the effect of neutral gas pressure on resistive bolometers"],"prefix":"10.1063","volume":"95","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-3905-2921","authenticated-orcid":false,"given":"N.","family":"Schoonheere","sequence":"first","affiliation":[{"name":"CEA, IRFM 1 , F-13108 Saint-Paul-les-Durance,","place":["France"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5327-4326","authenticated-orcid":false,"given":"C.","family":"Reux","sequence":"additional","affiliation":[{"name":"CEA, IRFM 1 , F-13108 Saint-Paul-les-Durance,","place":["France"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3751-7612","authenticated-orcid":false,"given":"H.","family":"Meister","sequence":"additional","affiliation":[{"name":"Max-Planck-Institut f\u00fcr Plasmaphysik 2 , D-85748 Garching,","place":["Germany"]}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-8736-6185","authenticated-orcid":false,"given":"P.","family":"Beyer","sequence":"additional","affiliation":[{"name":"Aix\u2013Marseille Universit\u00e9, CNRS 3 , PIIM UMR 7345, 13397 Marseille Cedex 20,","place":["France"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8480-0499","authenticated-orcid":false,"given":"P.","family":"Carvalho","sequence":"additional","affiliation":[{"name":"CCFE, Culham Science Centre 4 , Abingdon, Oxon OX14 3DB,","place":["United Kingdom"]}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6055-6045","authenticated-orcid":false,"given":"I.","family":"Coffey","sequence":"additional","affiliation":[{"name":"CCFE, Culham Science Centre 4 , Abingdon, Oxon OX14 3DB,","place":["United Kingdom"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1251-6392","authenticated-orcid":false,"given":"K.","family":"Lawson","sequence":"additional","affiliation":[{"name":"CCFE, Culham Science Centre 4 , Abingdon, Oxon OX14 3DB,","place":["United Kingdom"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4125-8465","authenticated-orcid":false,"given":"P.","family":"Puglia","sequence":"additional","affiliation":[{"name":"CEA, IRFM 1 , F-13108 Saint-Paul-les-Durance,","place":["France"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6207-2489","authenticated-orcid":false,"given":"U.","family":"Sheikh","sequence":"additional","affiliation":[{"name":"Ecole Polytechnique Federale de Lausanne (EPFL), Swiss Plasma Center (SPC) 5 , CH-1015 Lausanne,","place":["Switzerland"]}]},{"name":"JET Contributors","sequence":"additional","affiliation":[]},{"name":"the EUROfusion Tokamak Exploitation Team","sequence":"additional","affiliation":[]}],"member":"317","published-online":{"date-parts":[[2024,12,11]]},"reference":[{"key":"2024121114552782700_c1","doi-asserted-by":"publisher","first-page":"112012","DOI":"10.1088\/1741-4326\/ad3e16","article-title":"Overview of T and D\u2013T results in JET with ITER-like wall","volume":"64","year":"2024","journal-title":"Nucl. 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