Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models

Autores
Padilla, Nelson David; Salazar Albornoz, Salvador; Contreras, Sergio; Cora, Sofía Alejandra; Ruiz, Andrés Nicolás
Año de publicación
2014
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The angular momentum of galactic discs in semi-analytic models of galaxy formation is usually updated in time as material is accreted to the disc by adopting a constant dimensionless spin parameter and little attention is paid to the effects of accretion with misaligned angular momenta. These effects are the subject of this paper, where we adopt a Monte Carlo simulation for the changes in the direction of the angular momentum of a galaxy disc as it accretes matter based on accurate measurements from dark-matter haloes in the Millennium II simulation. In our semi-analytic model implementation, the flips seen in the dark-matter haloes are assumed to be the same for the cold baryons; however, we also assume that in the latter the flip also entails a difficulty for the disc to increase its angular momentum which causes the disc to become smaller relative to a no-flip case. This makes star formation to occur faster, especially in low-mass galaxies at all redshifts allowing galaxies to reach higher stellar masses faster. We adopt a new condition for the triggering of starbursts during mergers. As these produce the largest flips it is natural to adopt the disc instability criterion to evaluate the triggering of bursts in mergers instead of one based on mass ratios as in the original model. The new implementation reduces the average lifetimes of discs by a factor of ∼2, while still allowing old ages for the present-day discs of large spiral galaxies. It also provides a faster decline of star formation in massive galaxies and a better fit to the bright end of the luminosity function at z = 0.
Instituto de Astrofísica de La Plata
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Astronomía
galaxies: evolution
galaxies: fundamental parameters
galaxies: general
galaxies: structure
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/93561

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spelling Stochastic angular momentum slews and flips and their effect on discs in galaxy formation modelsPadilla, Nelson DavidSalazar Albornoz, SalvadorContreras, SergioCora, Sofía AlejandraRuiz, Andrés NicolásAstronomíagalaxies: evolutiongalaxies: fundamental parametersgalaxies: generalgalaxies: structureThe angular momentum of galactic discs in semi-analytic models of galaxy formation is usually updated in time as material is accreted to the disc by adopting a constant dimensionless spin parameter and little attention is paid to the effects of accretion with misaligned angular momenta. These effects are the subject of this paper, where we adopt a Monte Carlo simulation for the changes in the direction of the angular momentum of a galaxy disc as it accretes matter based on accurate measurements from dark-matter haloes in the Millennium II simulation. In our semi-analytic model implementation, the flips seen in the dark-matter haloes are assumed to be the same for the cold baryons; however, we also assume that in the latter the flip also entails a difficulty for the disc to increase its angular momentum which causes the disc to become smaller relative to a no-flip case. This makes star formation to occur faster, especially in low-mass galaxies at all redshifts allowing galaxies to reach higher stellar masses faster. We adopt a new condition for the triggering of starbursts during mergers. As these produce the largest flips it is natural to adopt the disc instability criterion to evaluate the triggering of bursts in mergers instead of one based on mass ratios as in the original model. The new implementation reduces the average lifetimes of discs by a factor of ∼2, while still allowing old ages for the present-day discs of large spiral galaxies. It also provides a faster decline of star formation in massive galaxies and a better fit to the bright end of the luminosity function at z = 0.Instituto de Astrofísica de La PlataFacultad de Ciencias Astronómicas y Geofísicas2014-08info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf2801-2814http://sedici.unlp.edu.ar/handle/10915/93561enginfo:eu-repo/semantics/altIdentifier/url/http://mnras.oxfordjournals.org/content/443/3/2801.fullinfo:eu-repo/semantics/altIdentifier/url/https://ri.conicet.gov.ar/handle/11336/35185info:eu-repo/semantics/altIdentifier/issn/0035-8711info:eu-repo/semantics/altIdentifier/doi/10.1093/mnras/stu1321info:eu-repo/semantics/altIdentifier/hdl/11336/35185info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:19:26Zoai:sedici.unlp.edu.ar:10915/93561Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:19:26.981SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
title Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
spellingShingle Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
Padilla, Nelson David
Astronomía
galaxies: evolution
galaxies: fundamental parameters
galaxies: general
galaxies: structure
title_short Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
title_full Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
title_fullStr Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
title_full_unstemmed Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
title_sort Stochastic angular momentum slews and flips and their effect on discs in galaxy formation models
dc.creator.none.fl_str_mv Padilla, Nelson David
Salazar Albornoz, Salvador
Contreras, Sergio
Cora, Sofía Alejandra
Ruiz, Andrés Nicolás
author Padilla, Nelson David
author_facet Padilla, Nelson David
Salazar Albornoz, Salvador
Contreras, Sergio
Cora, Sofía Alejandra
Ruiz, Andrés Nicolás
author_role author
author2 Salazar Albornoz, Salvador
Contreras, Sergio
Cora, Sofía Alejandra
Ruiz, Andrés Nicolás
author2_role author
author
author
author
dc.subject.none.fl_str_mv Astronomía
galaxies: evolution
galaxies: fundamental parameters
galaxies: general
galaxies: structure
topic Astronomía
galaxies: evolution
galaxies: fundamental parameters
galaxies: general
galaxies: structure
dc.description.none.fl_txt_mv The angular momentum of galactic discs in semi-analytic models of galaxy formation is usually updated in time as material is accreted to the disc by adopting a constant dimensionless spin parameter and little attention is paid to the effects of accretion with misaligned angular momenta. These effects are the subject of this paper, where we adopt a Monte Carlo simulation for the changes in the direction of the angular momentum of a galaxy disc as it accretes matter based on accurate measurements from dark-matter haloes in the Millennium II simulation. In our semi-analytic model implementation, the flips seen in the dark-matter haloes are assumed to be the same for the cold baryons; however, we also assume that in the latter the flip also entails a difficulty for the disc to increase its angular momentum which causes the disc to become smaller relative to a no-flip case. This makes star formation to occur faster, especially in low-mass galaxies at all redshifts allowing galaxies to reach higher stellar masses faster. We adopt a new condition for the triggering of starbursts during mergers. As these produce the largest flips it is natural to adopt the disc instability criterion to evaluate the triggering of bursts in mergers instead of one based on mass ratios as in the original model. The new implementation reduces the average lifetimes of discs by a factor of ∼2, while still allowing old ages for the present-day discs of large spiral galaxies. It also provides a faster decline of star formation in massive galaxies and a better fit to the bright end of the luminosity function at z = 0.
Instituto de Astrofísica de La Plata
Facultad de Ciencias Astronómicas y Geofísicas
description The angular momentum of galactic discs in semi-analytic models of galaxy formation is usually updated in time as material is accreted to the disc by adopting a constant dimensionless spin parameter and little attention is paid to the effects of accretion with misaligned angular momenta. These effects are the subject of this paper, where we adopt a Monte Carlo simulation for the changes in the direction of the angular momentum of a galaxy disc as it accretes matter based on accurate measurements from dark-matter haloes in the Millennium II simulation. In our semi-analytic model implementation, the flips seen in the dark-matter haloes are assumed to be the same for the cold baryons; however, we also assume that in the latter the flip also entails a difficulty for the disc to increase its angular momentum which causes the disc to become smaller relative to a no-flip case. This makes star formation to occur faster, especially in low-mass galaxies at all redshifts allowing galaxies to reach higher stellar masses faster. We adopt a new condition for the triggering of starbursts during mergers. As these produce the largest flips it is natural to adopt the disc instability criterion to evaluate the triggering of bursts in mergers instead of one based on mass ratios as in the original model. The new implementation reduces the average lifetimes of discs by a factor of ∼2, while still allowing old ages for the present-day discs of large spiral galaxies. It also provides a faster decline of star formation in massive galaxies and a better fit to the bright end of the luminosity function at z = 0.
publishDate 2014
dc.date.none.fl_str_mv 2014-08
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/93561
url http://sedici.unlp.edu.ar/handle/10915/93561
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/http://mnras.oxfordjournals.org/content/443/3/2801.full
info:eu-repo/semantics/altIdentifier/url/https://ri.conicet.gov.ar/handle/11336/35185
info:eu-repo/semantics/altIdentifier/issn/0035-8711
info:eu-repo/semantics/altIdentifier/doi/10.1093/mnras/stu1321
info:eu-repo/semantics/altIdentifier/hdl/11336/35185
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
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2801-2814
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repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
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