{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T20:19:47Z","timestamp":1775161187755,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,7,30]],"date-time":"2018-07-30T00:00:00Z","timestamp":1532908800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>A method for measuring the weak value of spin for atoms is proposed using a variant of the original Stern\u2013Gerlach apparatus. A full simulation of an experiment for observing the real part of the weak value using the impulsive approximation has been carried out. Our predictions show a displacement of the beam of helium atoms in the metastable 23S1 state, \u0394w, that is within the resolution of conventional microchannel plate detectors indicating that this type of experiment is feasible. Our analysis also determines the experimental parameters that will give an accurate determination of the weak value of spin. Preliminary experimental results are shown for helium, neon and argon in the 23S1 and 3P2 metastable states, respectively.<\/jats:p>","DOI":"10.3390\/e20080566","type":"journal-article","created":{"date-parts":[[2018,7,30]],"date-time":"2018-07-30T11:55:08Z","timestamp":1532951708000},"page":"566","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Method for Measuring the Weak Value of Spin for Metastable Atoms"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4124-1057","authenticated-orcid":false,"given":"Robert","family":"Flack","sequence":"first","affiliation":[{"name":"Department of Physics and Astronomy, University College, Gower Street, London WC1E 6BT, UK"}]},{"given":"Vincenzo","family":"Monachello","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University College, Gower Street, London WC1E 6BT, UK"}]},{"given":"Basil","family":"Hiley","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University College, Gower Street, London WC1E 6BT, UK"}]},{"given":"Peter","family":"Barker","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University College, Gower Street, London WC1E 6BT, UK"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1351","DOI":"10.1103\/PhysRevLett.60.1351","article-title":"How the Result of a Measurement of a Component of the Spin of a Spin-1\/2 Particle Can Turn Out to be 100","volume":"60","author":"Aharonov","year":"1988","journal-title":"Phys. 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