Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves
A kilonova is a short-lived explosive event in the Universe, resulting from the merger of two compact objects. Despite its importance as a primary source of heavy elements through r -process nucleosynthesis, its nature is not well understood due to its rarity. In this work, we introduce a model that...
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/ad06b0 |
| _version_ | 1797613727751602176 |
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| author | Donggeun Tak Z. Lucas Uhm James H. Gillanders |
| author_facet | Donggeun Tak Z. Lucas Uhm James H. Gillanders |
| author_sort | Donggeun Tak |
| collection | DOAJ |
| description | A kilonova is a short-lived explosive event in the Universe, resulting from the merger of two compact objects. Despite its importance as a primary source of heavy elements through r -process nucleosynthesis, its nature is not well understood due to its rarity. In this work, we introduce a model that determines the density of a radially stratified relativistic ejecta. We apply the model to kilonova ejecta and explore several hypothesized velocity profiles as a function of the merger’s ejection time. These velocity profiles result in diverse density profiles of the ejecta, for which we conduct radiative transfer simulations using tardis with the solar r -process composition. Consequently, we investigate the impact of the ejecta velocity profile on the resulting evolution of the lightcurve and spectra through the line transitions of heavy elements. The change in the rate at which these elements accumulate in the line-forming region leaves its imprint on the kilonova lightcurve at specific wavelengths, causing the lightcurves to decay at different rates. Furthermore, in several profiles, plateau-like behaviors (slow and/or flat decline) are also observed. In conclusion, this work proposes potential scenarios of the evolution of kilonova due to the ejecta velocity profile. |
| first_indexed | 2024-03-11T06:59:47Z |
| format | Article |
| id | doaj.art-9ee4e82af81049eb828c50cdbd540d43 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-11T06:59:47Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-9ee4e82af81049eb828c50cdbd540d432023-11-17T09:21:07ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01958212110.3847/1538-4357/ad06b0Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova LightcurvesDonggeun Tak0https://orcid.org/0000-0002-9852-2469Z. Lucas Uhm1James H. Gillanders2https://orcid.org/0000-0002-8094-6108SNU Astronomy Research Center, Seoul National University , Seoul 08826, Republic of Korea; Korea Astronomy and Space Science Institute , Daejeon 34055, Republic of Korea ; uhm@kasi.re.krKorea Astronomy and Space Science Institute , Daejeon 34055, Republic of Korea ; uhm@kasi.re.krAstrophysics sub-Department, Department of Physics, University of Oxford , Keble Road, Oxford, OX1 3RH, UKA kilonova is a short-lived explosive event in the Universe, resulting from the merger of two compact objects. Despite its importance as a primary source of heavy elements through r -process nucleosynthesis, its nature is not well understood due to its rarity. In this work, we introduce a model that determines the density of a radially stratified relativistic ejecta. We apply the model to kilonova ejecta and explore several hypothesized velocity profiles as a function of the merger’s ejection time. These velocity profiles result in diverse density profiles of the ejecta, for which we conduct radiative transfer simulations using tardis with the solar r -process composition. Consequently, we investigate the impact of the ejecta velocity profile on the resulting evolution of the lightcurve and spectra through the line transitions of heavy elements. The change in the rate at which these elements accumulate in the line-forming region leaves its imprint on the kilonova lightcurve at specific wavelengths, causing the lightcurves to decay at different rates. Furthermore, in several profiles, plateau-like behaviors (slow and/or flat decline) are also observed. In conclusion, this work proposes potential scenarios of the evolution of kilonova due to the ejecta velocity profile.https://doi.org/10.3847/1538-4357/ad06b0SupernovaeNeutron starsRadiative transfer |
| spellingShingle | Donggeun Tak Z. Lucas Uhm James H. Gillanders Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves The Astrophysical Journal Supernovae Neutron stars Radiative transfer |
| title | Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves |
| title_full | Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves |
| title_fullStr | Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves |
| title_full_unstemmed | Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves |
| title_short | Exploring the Impact of the Ejecta Velocity Profile on the Evolution of Kilonova: Diversity of the Kilonova Lightcurves |
| title_sort | exploring the impact of the ejecta velocity profile on the evolution of kilonova diversity of the kilonova lightcurves |
| topic | Supernovae Neutron stars Radiative transfer |
| url | https://doi.org/10.3847/1538-4357/ad06b0 |
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