{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:58:29Z","timestamp":1760147909036,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T00:00:00Z","timestamp":1678752000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>A relevant aspect of the interactions between charged fermions and crystal targets is coherence, which can exist at both classical and quantum levels. In the case of antiprotons crossing crystal targets, there are theories and measurements of classical-level coherence effects, in particular, channeling effects. For the present study, we assume the existence of a low-energy regime where the electrostatic interactions between an antiproton and the crystal atoms lead to a local loss in the beam flux as their leading effect. We expect this assumption to be well-justified for antiproton (p\u00af) energies below 100 eV, with a progressive transition to a standard \u201cRutherford regime\u201d in the energy range 100\u20131000 eV. Under these conditions, the target can be treated as an optical absorber with a periodical structure, which can be simplified by considering a multi-layer planar structure only. As in standard optics, wave absorption is accompanied by interference and diffraction. Assuming sub-nanometer ranges for the relevant parameters and a realistic angular spread for the antiproton beam, we find narrow-angle focusing effects that reproduce the classical channeling effect at a qualitative level. We also find that diffraction dominates over interference, although this may strongly depend on the target details.<\/jats:p>","DOI":"10.3390\/sym15030724","type":"journal-article","created":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T06:57:11Z","timestamp":1678777031000},"page":"724","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optical Channeling of Low Energy Antiprotons in Thin Crystal Targets"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5647-0624","authenticated-orcid":false,"given":"Andrea","family":"Bianconi","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7875-5815","authenticated-orcid":false,"given":"Giovanni","family":"Costantini","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giulia","family":"Gosta","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marco","family":"Leali","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3612-1608","authenticated-orcid":false,"given":"Valerio","family":"Mascagna","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano","family":"Migliorati","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7865-8820","authenticated-orcid":false,"given":"Luca","family":"Venturelli","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Informazione, Universit\u00e0 degli Studi di Brescia, Via Branze 38, I-25123 Brescia, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, I-27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"021603","DOI":"10.1103\/PhysRevLett.121.021603","article-title":"Strong Reduction of the Effective Radiation Length in an Axially Oriented Scintillator Crystal","volume":"121","author":"Bandiera","year":"2018","journal-title":"Phys. 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