The Consequences of Assuming m=0 for Global Model-Fitting
A recent re-analysis of Whole Earth Telescope observations of GD 358 obtained in 1990 suggest that asteroseismology of additional DBV white dwarfs can lead to independent constraints on the important, but poorly determined, 12C(α, γ)16O nuclear reaction rate. Data exist for several other DBV white d...
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| Format: | Article |
| Language: | English |
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De Gruyter
2003-06-01
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| Series: | Open Astronomy |
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| Online Access: | https://doi.org/10.1515/astro-2017-0048 |
| _version_ | 1818665103623454720 |
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| author | Metcalfe Travis S. |
| author_facet | Metcalfe Travis S. |
| author_sort | Metcalfe Travis S. |
| collection | DOAJ |
| description | A recent re-analysis of Whole Earth Telescope observations of GD 358 obtained in 1990 suggest that asteroseismology of additional DBV white dwarfs can lead to independent constraints on the important, but poorly determined, 12C(α, γ)16O nuclear reaction rate. Data exist for several other DBV white dwarfs, but relatively few modes are detected and there is often no multiplet structure to aid in the identification of the spherical harmonic indices l,m. I use a new grid of one million DBV models covering a broad range of masses, temperatures, and surface helium layer masses to investigate the consequences of assuming m=0 for global model-fitting. I find that when the spherical degree is known and the rotation period is of order 1 day, the model-fitting procedure applied to modes with unknown m values will still correctly identify the families of possible solutions, and has a high probability of identifying the same globally optimal solution found when the m-value is known. |
| first_indexed | 2024-12-17T05:43:19Z |
| format | Article |
| id | doaj.art-096fd9bec85a45ea9d1197ef9d157b0b |
| institution | Directory Open Access Journal |
| issn | 2543-6376 |
| language | English |
| last_indexed | 2024-12-17T05:43:19Z |
| publishDate | 2003-06-01 |
| publisher | De Gruyter |
| record_format | Article |
| series | Open Astronomy |
| spelling | doaj.art-096fd9bec85a45ea9d1197ef9d157b0b2022-12-21T22:01:22ZengDe GruyterOpen Astronomy2543-63762003-06-0112224725110.1515/astro-2017-0048astro-2017-0048The Consequences of Assuming m=0 for Global Model-FittingMetcalfe Travis S.0Theoretical Astrophysics Center, Aarhus University, DanmarkA recent re-analysis of Whole Earth Telescope observations of GD 358 obtained in 1990 suggest that asteroseismology of additional DBV white dwarfs can lead to independent constraints on the important, but poorly determined, 12C(α, γ)16O nuclear reaction rate. Data exist for several other DBV white dwarfs, but relatively few modes are detected and there is often no multiplet structure to aid in the identification of the spherical harmonic indices l,m. I use a new grid of one million DBV models covering a broad range of masses, temperatures, and surface helium layer masses to investigate the consequences of assuming m=0 for global model-fitting. I find that when the spherical degree is known and the rotation period is of order 1 day, the model-fitting procedure applied to modes with unknown m values will still correctly identify the families of possible solutions, and has a high probability of identifying the same globally optimal solution found when the m-value is known.https://doi.org/10.1515/astro-2017-0048methodsnumerical-starsindividual (gd 358)-starsoscillations-starswhite dwarfs |
| spellingShingle | Metcalfe Travis S. The Consequences of Assuming m=0 for Global Model-Fitting Open Astronomy methods numerical-stars individual (gd 358)-stars oscillations-stars white dwarfs |
| title | The Consequences of Assuming m=0 for Global Model-Fitting |
| title_full | The Consequences of Assuming m=0 for Global Model-Fitting |
| title_fullStr | The Consequences of Assuming m=0 for Global Model-Fitting |
| title_full_unstemmed | The Consequences of Assuming m=0 for Global Model-Fitting |
| title_short | The Consequences of Assuming m=0 for Global Model-Fitting |
| title_sort | consequences of assuming m 0 for global model fitting |
| topic | methods numerical-stars individual (gd 358)-stars oscillations-stars white dwarfs |
| url | https://doi.org/10.1515/astro-2017-0048 |
| work_keys_str_mv | AT metcalfetraviss theconsequencesofassumingm0forglobalmodelfitting AT metcalfetraviss consequencesofassumingm0forglobalmodelfitting |