{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T18:36:25Z","timestamp":1761762985565,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,2,12]],"date-time":"2015-02-12T00:00:00Z","timestamp":1423699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The measurement of ionizing radiation (IR) is a crucial issue in different areas of interest, from environmental safety and industrial monitoring to aerospace and medicine. Optical fiber sensors have recently proven good candidates as radiation dosimeters. Here we investigate the effect of IR on germanosilicate optical fibers. A piece of Ge-doped fiber enclosed between two fiber Bragg gratings (FBGs) is irradiated with gamma radiation generated by a 6 MV medical linear accelerator. With respect to other FBG-based IR dosimeters, here the sensor is only the bare fiber without any special internal structure.  A near infrared laser is frequency locked to the cavity modes for high resolution measurement of radiation induced effects on the fiber optical parameters. In particular, we observe a variation of the fiber thermo-optic response with the radiation dose delivered, as expected from the interaction with Ge defect centers, and demonstrate a detection limit of 360 mGy. This method can have an impact in those contexts where low radiation doses have to be measured both in small volumes or over large areas, such as radiation therapy and radiation protection, while bare optical fibers are cheap and disposable.<\/jats:p>","DOI":"10.3390\/s150204242","type":"journal-article","created":{"date-parts":[[2015,2,12]],"date-time":"2015-02-12T12:08:24Z","timestamp":1423742904000},"page":"4242-4252","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Ionizing Radiation Detectors Based on Ge-Doped Optical Fibers Inserted in Resonant Cavities"],"prefix":"10.3390","volume":"15","author":[{"given":"Saverio","family":"Avino","sequence":"first","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO),  via Campi Flegrei 34\u2014Comprensorio A. Olivetti, 80078 Pozzuoli (Na), Italy"}]},{"given":"Vittoria","family":"D'Avino","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto di Biostrutture e Bioimmagini,  via Tommaso De Amicis 95, 80131 Napoli, Italy"}]},{"given":"Antonio","family":"Giorgini","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO),  via Campi Flegrei 34\u2014Comprensorio A. Olivetti, 80078 Pozzuoli (Na), Italy"}]},{"given":"Roberto","family":"Pacelli","sequence":"additional","affiliation":[{"name":"Universit\u00e0 di Napoli Federico II, Dipartimento di Scienze Biomediche Avanzate,  via Pansini 5, 80131 Napoli, Italy"}]},{"given":"Raffaele","family":"Liuzzi","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto di Biostrutture e Bioimmagini,  via Tommaso De Amicis 95, 80131 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0058-4029","authenticated-orcid":false,"given":"Laura","family":"Cella","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto di Biostrutture e Bioimmagini,  via Tommaso De Amicis 95, 80131 Napoli, Italy"}]},{"given":"Paolo","family":"De Natale","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO), Largo Enrico Fermi 6, 50125 Firenze, Italy"}]},{"given":"Gianluca","family":"Gagliardi","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO),  via Campi Flegrei 34\u2014Comprensorio A. Olivetti, 80078 Pozzuoli (Na), Italy"}]}],"member":"1968","published-online":{"date-parts":[[2015,2,12]]},"reference":[{"key":"ref_1","unstructured":"(1980). Radiation Quantities and Units, ICRU. ICRU Report 33."},{"key":"ref_2","unstructured":"Webb, S. (1997). The Physics of Three-Dimensional Radiation Therapy\u2014Advances in Technology, IOP Publishing Ltd."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"(2001). Intensity Modulated radiation Collaborative Working Group, Intensity-modulated radiotherapy. Current status and issues of interest. Int. J. Radiat. Oncol. Biol. Phys., 51, 880\u2013914.","DOI":"10.1016\/S0360-3016(01)01749-7"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2081","DOI":"10.1088\/0031-9155\/48\/14\/304","article-title":"Ionization chamber dosimetry of small photon fields: A Monte Carlo study on stopping-power ratios for radiosurgery and IMRT beams","volume":"48","author":"Andreo","year":"2003","journal-title":"Phys. Med. 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