Principal Component analysis studies of turbulence in optically thick gas
Autor(a) principal: | |
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Data de Publicação: | 2016 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFRN |
Texto Completo: | https://repositorio.ufrn.br/jspui/handle/123456789/29116 |
Resumo: | In this work we investigate the sensitivity of principal component analysis (PCA) to the velocity power spectrum in high-opacity regimes of the interstellar medium (ISM). For our analysis we use synthetic position–position–velocity (PPV) cubes of fractional Brownian motion and magnetohydrodynamics (MHD) simulations, post-processed to include radiative transfer effects from CO. We find that PCA analysis is very different from the tools based on the traditional power spectrum of PPV data cubes. Our major finding is that PCA is also sensitive to the phase information of PPV cubes and this allows PCA to detect the changes of the underlying velocity and density spectra at high opacities, where the spectral analysis of the maps provides the universal −3 spectrum in accordance with the predictions of the Lazarian & Pogosyan theory. This makes PCA a potentially valuable tool for studies of turbulence at high opacities, provided that proper gauging of the PCA index is made. However, we found the latter to not be easy, as the PCA results change in an irregular way for data with high sonic Mach numbers. This is in contrast to synthetic Brownian noise data used for velocity and density fields that show monotonic PCA behavior. We attribute this difference to the PCA's sensitivity to Fourier phase information. |
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Correia, C.Lazarian, A.Burkhart, B.Pogosya, D.Medeiros, José Renan de2020-06-01T02:33:19Z2020-06-01T02:33:19Z2016CORREIA, C. ; LAZARIAN, A. ; BURKHART, B. ; POGOSYAN, D. ; MEDEIROS, J. R. de . Principal Component analysis studies os turbulence in optically thick gas. The Astrophysical Journal, v. 818, p. 118, 2016. Disponível em: http://iopscience.iop.org/article/10.3847/0004-637X/818/2/118/meta. Acesso em: 20 Maio 2020. http://dx.doi.org/10.3847/0004-637X/818/2/118https://repositorio.ufrn.br/jspui/handle/123456789/2911610.3847/0004-637X/818/2/118Sociedade Astronômica AmericanaStructure – magnetohydrodynamicsPrincipal Component analysis studies of turbulence in optically thick gasinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleIn this work we investigate the sensitivity of principal component analysis (PCA) to the velocity power spectrum in high-opacity regimes of the interstellar medium (ISM). For our analysis we use synthetic position–position–velocity (PPV) cubes of fractional Brownian motion and magnetohydrodynamics (MHD) simulations, post-processed to include radiative transfer effects from CO. We find that PCA analysis is very different from the tools based on the traditional power spectrum of PPV data cubes. Our major finding is that PCA is also sensitive to the phase information of PPV cubes and this allows PCA to detect the changes of the underlying velocity and density spectra at high opacities, where the spectral analysis of the maps provides the universal −3 spectrum in accordance with the predictions of the Lazarian & Pogosyan theory. This makes PCA a potentially valuable tool for studies of turbulence at high opacities, provided that proper gauging of the PCA index is made. However, we found the latter to not be easy, as the PCA results change in an irregular way for data with high sonic Mach numbers. This is in contrast to synthetic Brownian noise data used for velocity and density fields that show monotonic PCA behavior. We attribute this difference to the PCA's sensitivity to Fourier phase information.engreponame:Repositório Institucional da UFRNinstname:Universidade Federal do Rio Grande do Norte (UFRN)instacron:UFRNinfo:eu-repo/semantics/openAccessLICENSElicense.txtlicense.txttext/plain; charset=utf-81484https://repositorio.ufrn.br/bitstream/123456789/29116/2/license.txte9597aa2854d128fd968be5edc8a28d9MD52TEXTPrincipalComponentAnalysisStudies_Medeiros_2016.pdf.txtPrincipalComponentAnalysisStudies_Medeiros_2016.pdf.txtExtracted texttext/plain34793https://repositorio.ufrn.br/bitstream/123456789/29116/3/PrincipalComponentAnalysisStudies_Medeiros_2016.pdf.txt3597584fb9c88321abe1366fdb17b5aaMD53THUMBNAILPrincipalComponentAnalysisStudies_Medeiros_2016.pdf.jpgPrincipalComponentAnalysisStudies_Medeiros_2016.pdf.jpgGenerated Thumbnailimage/jpeg1831https://repositorio.ufrn.br/bitstream/123456789/29116/4/PrincipalComponentAnalysisStudies_Medeiros_2016.pdf.jpg155a672f989da7084b0c8057224856fcMD54123456789/291162022-10-20 17:55:57.542oai:https://repositorio.ufrn.br:123456789/29116Tk9OLUVYQ0xVU0lWRSBESVNUUklCVVRJT04gTElDRU5TRQoKCkJ5IHNpZ25pbmcgYW5kIGRlbGl2ZXJpbmcgdGhpcyBsaWNlbnNlLCBNci4gKGF1dGhvciBvciBjb3B5cmlnaHQgaG9sZGVyKToKCgphKSBHcmFudHMgdGhlIFVuaXZlcnNpZGFkZSBGZWRlcmFsIFJpbyBHcmFuZGUgZG8gTm9ydGUgdGhlIG5vbi1leGNsdXNpdmUgcmlnaHQgb2YKcmVwcm9kdWNlLCBjb252ZXJ0IChhcyBkZWZpbmVkIGJlbG93KSwgY29tbXVuaWNhdGUgYW5kIC8gb3IKZGlzdHJpYnV0ZSB0aGUgZGVsaXZlcmVkIGRvY3VtZW50IChpbmNsdWRpbmcgYWJzdHJhY3QgLyBhYnN0cmFjdCkgaW4KZGlnaXRhbCBvciBwcmludGVkIGZvcm1hdCBhbmQgaW4gYW55IG1lZGl1bS4KCmIpIERlY2xhcmVzIHRoYXQgdGhlIGRvY3VtZW50IHN1Ym1pdHRlZCBpcyBpdHMgb3JpZ2luYWwgd29yaywgYW5kIHRoYXQKeW91IGhhdmUgdGhlIHJpZ2h0IHRvIGdyYW50IHRoZSByaWdodHMgY29udGFpbmVkIGluIHRoaXMgbGljZW5zZS4gRGVjbGFyZXMKdGhhdCB0aGUgZGVsaXZlcnkgb2YgdGhlIGRvY3VtZW50IGRvZXMgbm90IGluZnJpbmdlLCBhcyBmYXIgYXMgaXQgaXMKdGhlIHJpZ2h0cyBvZiBhbnkgb3RoZXIgcGVyc29uIG9yIGVudGl0eS4KCmMpIElmIHRoZSBkb2N1bWVudCBkZWxpdmVyZWQgY29udGFpbnMgbWF0ZXJpYWwgd2hpY2ggZG9lcyBub3QKcmlnaHRzLCBkZWNsYXJlcyB0aGF0IGl0IGhhcyBvYnRhaW5lZCBhdXRob3JpemF0aW9uIGZyb20gdGhlIGhvbGRlciBvZiB0aGUKY29weXJpZ2h0IHRvIGdyYW50IHRoZSBVbml2ZXJzaWRhZGUgRmVkZXJhbCBkbyBSaW8gR3JhbmRlIGRvIE5vcnRlIHRoZSByaWdodHMgcmVxdWlyZWQgYnkgdGhpcyBsaWNlbnNlLCBhbmQgdGhhdCB0aGlzIG1hdGVyaWFsIHdob3NlIHJpZ2h0cyBhcmUgb2YKdGhpcmQgcGFydGllcyBpcyBjbGVhcmx5IGlkZW50aWZpZWQgYW5kIHJlY29nbml6ZWQgaW4gdGhlIHRleHQgb3IKY29udGVudCBvZiB0aGUgZG9jdW1lbnQgZGVsaXZlcmVkLgoKSWYgdGhlIGRvY3VtZW50IHN1Ym1pdHRlZCBpcyBiYXNlZCBvbiBmdW5kZWQgb3Igc3VwcG9ydGVkIHdvcmsKYnkgYW5vdGhlciBpbnN0aXR1dGlvbiBvdGhlciB0aGFuIHRoZSBVbml2ZXJzaWRhZGUgRmVkZXJhbCBkbyBSaW8gR3JhbmRlIGRvIE5vcnRlLCBkZWNsYXJlcyB0aGF0IGl0IGhhcyBmdWxmaWxsZWQgYW55IG9ibGlnYXRpb25zIHJlcXVpcmVkIGJ5IHRoZSByZXNwZWN0aXZlIGFncmVlbWVudCBvciBhZ3JlZW1lbnQuCgpUaGUgVW5pdmVyc2lkYWRlIEZlZGVyYWwgZG8gUmlvIEdyYW5kZSBkbyBOb3J0ZSB3aWxsIGNsZWFybHkgaWRlbnRpZnkgaXRzIG5hbWUgKHMpIGFzIHRoZSBhdXRob3IgKHMpIG9yIGhvbGRlciAocykgb2YgdGhlIGRvY3VtZW50J3MgcmlnaHRzCmRlbGl2ZXJlZCwgYW5kIHdpbGwgbm90IG1ha2UgYW55IGNoYW5nZXMsIG90aGVyIHRoYW4gdGhvc2UgcGVybWl0dGVkIGJ5CnRoaXMgbGljZW5zZQo=Repositório de PublicaçõesPUBhttp://repositorio.ufrn.br/oai/opendoar:2022-10-20T20:55:57Repositório Institucional da UFRN - Universidade Federal do Rio Grande do Norte (UFRN)false |
dc.title.pt_BR.fl_str_mv |
Principal Component analysis studies of turbulence in optically thick gas |
title |
Principal Component analysis studies of turbulence in optically thick gas |
spellingShingle |
Principal Component analysis studies of turbulence in optically thick gas Correia, C. Structure – magnetohydrodynamics |
title_short |
Principal Component analysis studies of turbulence in optically thick gas |
title_full |
Principal Component analysis studies of turbulence in optically thick gas |
title_fullStr |
Principal Component analysis studies of turbulence in optically thick gas |
title_full_unstemmed |
Principal Component analysis studies of turbulence in optically thick gas |
title_sort |
Principal Component analysis studies of turbulence in optically thick gas |
author |
Correia, C. |
author_facet |
Correia, C. Lazarian, A. Burkhart, B. Pogosya, D. Medeiros, José Renan de |
author_role |
author |
author2 |
Lazarian, A. Burkhart, B. Pogosya, D. Medeiros, José Renan de |
author2_role |
author author author author |
dc.contributor.author.fl_str_mv |
Correia, C. Lazarian, A. Burkhart, B. Pogosya, D. Medeiros, José Renan de |
dc.subject.por.fl_str_mv |
Structure – magnetohydrodynamics |
topic |
Structure – magnetohydrodynamics |
description |
In this work we investigate the sensitivity of principal component analysis (PCA) to the velocity power spectrum in high-opacity regimes of the interstellar medium (ISM). For our analysis we use synthetic position–position–velocity (PPV) cubes of fractional Brownian motion and magnetohydrodynamics (MHD) simulations, post-processed to include radiative transfer effects from CO. We find that PCA analysis is very different from the tools based on the traditional power spectrum of PPV data cubes. Our major finding is that PCA is also sensitive to the phase information of PPV cubes and this allows PCA to detect the changes of the underlying velocity and density spectra at high opacities, where the spectral analysis of the maps provides the universal −3 spectrum in accordance with the predictions of the Lazarian & Pogosyan theory. This makes PCA a potentially valuable tool for studies of turbulence at high opacities, provided that proper gauging of the PCA index is made. However, we found the latter to not be easy, as the PCA results change in an irregular way for data with high sonic Mach numbers. This is in contrast to synthetic Brownian noise data used for velocity and density fields that show monotonic PCA behavior. We attribute this difference to the PCA's sensitivity to Fourier phase information. |
publishDate |
2016 |
dc.date.issued.fl_str_mv |
2016 |
dc.date.accessioned.fl_str_mv |
2020-06-01T02:33:19Z |
dc.date.available.fl_str_mv |
2020-06-01T02:33:19Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
CORREIA, C. ; LAZARIAN, A. ; BURKHART, B. ; POGOSYAN, D. ; MEDEIROS, J. R. de . Principal Component analysis studies os turbulence in optically thick gas. The Astrophysical Journal, v. 818, p. 118, 2016. Disponível em: http://iopscience.iop.org/article/10.3847/0004-637X/818/2/118/meta. Acesso em: 20 Maio 2020. http://dx.doi.org/10.3847/0004-637X/818/2/118 |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufrn.br/jspui/handle/123456789/29116 |
dc.identifier.doi.none.fl_str_mv |
10.3847/0004-637X/818/2/118 |
identifier_str_mv |
CORREIA, C. ; LAZARIAN, A. ; BURKHART, B. ; POGOSYAN, D. ; MEDEIROS, J. R. de . Principal Component analysis studies os turbulence in optically thick gas. The Astrophysical Journal, v. 818, p. 118, 2016. Disponível em: http://iopscience.iop.org/article/10.3847/0004-637X/818/2/118/meta. Acesso em: 20 Maio 2020. http://dx.doi.org/10.3847/0004-637X/818/2/118 10.3847/0004-637X/818/2/118 |
url |
https://repositorio.ufrn.br/jspui/handle/123456789/29116 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Sociedade Astronômica Americana |
publisher.none.fl_str_mv |
Sociedade Astronômica Americana |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFRN instname:Universidade Federal do Rio Grande do Norte (UFRN) instacron:UFRN |
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Universidade Federal do Rio Grande do Norte (UFRN) |
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UFRN |
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UFRN |
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Repositório Institucional da UFRN |
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Repositório Institucional da UFRN |
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