{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T17:08:34Z","timestamp":1769879314558,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,15]],"date-time":"2020-12-15T00:00:00Z","timestamp":1607990400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003407","name":"Ministero dell\u2019Istruzione, dell\u2019Universit\u00e0 e della Ricerca","doi-asserted-by":"publisher","award":["2017APKP7T"],"award-info":[{"award-number":["2017APKP7T"]}],"id":[{"id":"10.13039\/501100003407","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>In the past decades, there has been an increasing literature on the presence of an inertial energy cascade in interplanetary space plasma, being interpreted as the signature of Magnetohydrodynamic turbulence (MHD) for both fields and passive scalars. Here, we investigate the passive scalar nature of the solar wind proton density and temperature by looking for scaling features in the mixed-scalar third-order structure functions using measurements on-board the Ulysses spacecraft during two different periods, i.e., an equatorial slow solar wind and a high-latitude fast solar wind, respectively. We find a linear scaling of the mixed third-order structure function as predicted by Yaglom\u2019s law for passive scalars in the case of slow solar wind, while the results for fast solar wind suggest that the mixed fourth-order structure function displays a linear scaling. A simple empirical explanation of the observed difference is proposed and discussed.<\/jats:p>","DOI":"10.3390\/e22121419","type":"journal-article","created":{"date-parts":[[2020,12,15]],"date-time":"2020-12-15T21:11:02Z","timestamp":1608066662000},"page":"1419","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["On Yaglom\u2019s Law for the Interplanetary Proton Density and Temperature Fluctuations in Solar Wind Turbulence"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3403-647X","authenticated-orcid":false,"given":"Giuseppe","family":"Consolini","sequence":"first","affiliation":[{"name":"INAF-Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere, 100, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6096-0220","authenticated-orcid":false,"given":"Tommaso","family":"Alberti","sequence":"additional","affiliation":[{"name":"INAF-Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere, 100, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3182-6679","authenticated-orcid":false,"given":"Vincenzo","family":"Carbone","sequence":"additional","affiliation":[{"name":"Dipartimento di Fisica, Universit\u00e0 della Calabria, Ponte P. Bucci, 87036 Rende, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bruno, R., and Carbone, V. (2016). Turbulence in the Solar Wind, Springer.","DOI":"10.1007\/978-3-319-43440-7"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/BF00748891","article-title":"Magnetohydrodynamic Structures Waves and Turbulence in the Solar Wind-Observations and Theories","volume":"73","author":"Tu","year":"1995","journal-title":"Space Sci. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Frisch, U. (1995). Turbulence. The Legacy of A.N. 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