{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T16:55:59Z","timestamp":1790960159282,"version":"4.1.0"},"reference-count":51,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"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>Soil moisture sensors in hyper-arid rangeland face temperatures beyond the range over which their electronics are specified, yet insulation placed around a neutron detector is a scatterer and risks being read as a change in soil water. We evaluate this trade-off computationally for a helium-3-free, boron-10-lined cosmic-ray neutron sensor fitted with an external hydrophobic silica aerogel sleeve. A voxel model of the instrument in a domain of its own size gives response functions, normalized to a maximum of 1.0 and applied to the spectrum of a 1000 m field simulation with no detector. A 20 mm sleeve raises the weighted epithermal count by 3.0%, constant to 0.0007 across a factor of six in soil water. The wet-to-dry scaling factor N(0.05)\/N(0.30) is 2.1533\u00b10.0161 bare and 2.1530\u00b10.0160 sleeved, a ratio of 0.9999. The sleeve changes the count rate and not the moisture response, and the offset is absorbed into the calibration constant when calibration follows assembly. A diurnal thermal calculation gives an interior peak of 59.9 \u00b0C bare against a specified limit of 45 \u00b0C, and 40.7 \u00b0C sleeved. Every result is from simulation; field deployment remains future work.<\/jats:p>","DOI":"10.3390\/s26196266","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T16:50:38Z","timestamp":1790959838000},"page":"6266","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hydrophobic Silica Aerogel Thermal Protection for a Low-Power, Helium-3-Free Cosmic-Ray Neutron Soil Moisture Sensor in Hyper-Arid Rangeland"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-9216-4444","authenticated-orcid":false,"given":"Nujud","family":"Badawi","sequence":"first","affiliation":[{"name":"Department of Physics, College of Science, University of Hafr Al Batin (UHB), Al Jamiah, Hafr Al Batin 39524, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1679-0225","authenticated-orcid":false,"given":"Abdel Nasser","family":"Tawfik","sequence":"additional","affiliation":[{"name":"Department of Physics, Islamic University of Madinah, Madinah 42351, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3758-2385","authenticated-orcid":false,"given":"Abousrie A.","family":"Farag","sequence":"additional","affiliation":[{"name":"Department of Agricultural Systems Engineering, College of Agricultural and Food Sciences, King Faisal University, Al-Ahsa 31982, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"validation","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8795-2470","authenticated-orcid":false,"given":"Azzah Aziz","family":"AlShehri","sequence":"additional","affiliation":[{"name":"Department of Science and Technology, University College at Nairiyah, University of Hafr Al Batin (UHB), Nairiyah 31981, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5772","DOI":"10.1002\/2015WR017169","article-title":"Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons","volume":"51","author":"Zreda","year":"2015","journal-title":"Water Resour. 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