{"id":298,"date":"2025-11-15T11:22:34","date_gmt":"2025-11-15T11:22:34","guid":{"rendered":"https:\/\/astroadnan.com\/?p=298"},"modified":"2025-11-15T11:58:53","modified_gmt":"2025-11-15T11:58:53","slug":"brown-dwarf-formation-through-gravitational-collapse-insights-from-3d-numerical-simulations","status":"publish","type":"post","link":"https:\/\/astroadnan.com\/index.php\/2025\/11\/15\/brown-dwarf-formation-through-gravitational-collapse-insights-from-3d-numerical-simulations\/","title":{"rendered":"Brown Dwarf Formation through Gravitational Collapse: Insights from 3D Numerical Simulations"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The formation mechanism of Brown Dwarfs (BDs), whether akin to stars or ejected planetary-mass objects, remains debated. We present the first 3D radiation-MHD simulations of magnetized, turbulent, gravitationally unstable low-mass cores<math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><mo stretchy=\"false\">(<\/mo><\/math> <mn>0.05<\/mn> <mo>\u22120.1&nbsp;<\/mo><mrow data-mjx-texclass=\"ORD\"><msub><mi mathvariant=\"normal\">M<mo><sub>\u2299<\/sub><\/mo><\/mi><\/msub>)<\/mrow> collapsing into proto-BDs. Using the RAMSES code with adaptive mesh refinement, we model the full dynamical range<math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><\/math><mo stretchy=\"false\">(<\/mo><msup> <mn>10<\/mn><mrow data-mjx-texclass=\"ORD\"><sup><mn>5<\/mn><\/sup><\/mrow><\/msup> <mtext>&nbsp;\u2212<\/mtext> <msup><mn>10<\/mn><sup><mrow data-mjx-texclass=\"ORD\"><mn>22<\/mn><\/mrow>&nbsp;<\/sup><\/msup> <mrow data-mjx-texclass=\"ORD\"><msup><mi data-mjx-auto-op=\"false\">cm<mo><sup>\u22123<\/sup><\/mo><\/mi><\/msup>)<\/mrow>, including radiative transfer (flux limited diffusion) and non-ideal MHD (ambipolar diffusion). <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Our simulations self-consistently follow the isothermal collapse, first hydrostatic core formation, H$_{2}$ dissociation, and BD birth.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The resulting BDs have initial radii <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><\/math> <mo>\u2248 0.75<\/mo> <mrow data-mjx-texclass=\"ORD\"><msub><mi mathvariant=\"normal\">R<sub> <mo>\u2299<\/mo><\/sub> <\/mi><\/msub><\/mrow> and masses <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><\/math> <mo>\u2248<\/mo> <mn>0.8<\/mn> <mrow data-mjx-texclass=\"ORD\"><msub><mi mathvariant=\"normal\">M<mi data-mjx-auto-op=\"false\"><sub>Jup<\/sub><\/mi><\/mi> <\/msub><\/mrow>, growing via accretion as we follow the early evolution of the object. Crucially, we find that BDs may form similarly to low-mass stars but with a prolonged first-core phase, supporting a star-like formation scenario.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Recommended citation: Adnan Ali Ahmad, Beno\u00eet Commer\u00e7on, Gilles Chabrier, and Antonin Borderies, ApJL 991 L32 (2025) <\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link has-white-color has-text-color has-link-color wp-element-button\" href=\"https:\/\/ui.adsabs.harvard.edu\/abs\/2025ApJ...991L..32A\/abstract\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Download Paper<\/strong><\/a><\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The formation mechanism of Brown Dwarfs (BDs), whether akin to stars or ejected planetary-mass objects, remains debated. We present the first 3D radiation-MHD simulations of magnetized, turbulent, gravitationally unstable low-mass cores( 0.05 \u22120.1&nbsp;M\u2299) collapsing into proto-BDs. Using the RAMSES code with adaptive mesh refinement, we model the full dynamical range( 105 &nbsp;\u2212 1022&nbsp; cm\u22123), including [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-298","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/posts\/298","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/comments?post=298"}],"version-history":[{"count":6,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/posts\/298\/revisions"}],"predecessor-version":[{"id":323,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/posts\/298\/revisions\/323"}],"wp:attachment":[{"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/media?parent=298"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/categories?post=298"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/astroadnan.com\/index.php\/wp-json\/wp\/v2\/tags?post=298"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}