Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data
Studying compact-star binaries and their mergers is integral to determining progenitors for observable transients. Today, compact-star mergers are typically studied via state-of-the-art computational fluid dynamics codes. One such numerical technique, smoothed particle hydrodynamics (SPH), is freque...
| Main Authors: | , , , , |
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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/acd75a |
| _version_ | 1797698314597040128 |
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| author | M. Alexander R. Kaltenborn Michael J. Falato Oleg Korobkin Irina Sagert Wesley P. Even |
| author_facet | M. Alexander R. Kaltenborn Michael J. Falato Oleg Korobkin Irina Sagert Wesley P. Even |
| author_sort | M. Alexander R. Kaltenborn |
| collection | DOAJ |
| description | Studying compact-star binaries and their mergers is integral to determining progenitors for observable transients. Today, compact-star mergers are typically studied via state-of-the-art computational fluid dynamics codes. One such numerical technique, smoothed particle hydrodynamics (SPH), is frequently chosen for its excellent mass, energy, and momentum conservation. The natural treatment of vacuum and the ability to represent highly irregular morphologies make SPH an excellent tool for the study of compact-star binaries and mergers. For many scenarios, including binary systems, the outcome of simulations is only as accurate as the initial conditions. For SPH, it is essential to ensure that the particles are distributed regularly, representing the initial density profile but without long-range correlations. Particle noise in the form of high-frequency local motion and low-frequency global dynamics must be damped out. Damping the latter can be as computationally intensive as the actual simulation. We discuss a new and straightforward relaxation method, halted-pendulum relaxation (HPR), to remove global oscillation modes of SPH particle configurations. In combination with effective external potentials representing gravitational and orbital forces, we show that HPR has an excellent performance in efficiently relaxing SPH particles to the desired density distribution and removing global oscillation modes. We compare the method to frequently used relaxation approaches and test it on a white dwarf binary model at its Roche-lobe overflow limit. We highlight the importance of our method in achieving accurate initial conditions and its effect on achieving circular orbits and realistic accretion rates when compared with other general relaxation methods. |
| first_indexed | 2024-03-12T03:52:28Z |
| format | Article |
| id | doaj.art-6940d4c64d8a4faea96f3b97ffa8c344 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T03:52:28Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-6940d4c64d8a4faea96f3b97ffa8c3442023-09-03T12:16:06ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-0195216010.3847/1538-4357/acd75aHalted-pendulum Relaxation: Application to White Dwarf Binary Initial DataM. Alexander R. Kaltenborn0https://orcid.org/0000-0002-9604-7908Michael J. Falato1https://orcid.org/0000-0002-4510-7325Oleg Korobkin2https://orcid.org/0000-0003-4156-5342Irina Sagert3https://orcid.org/0000-0002-1487-0360Wesley P. Even4https://orcid.org/0000-0002-5412-3618Center for Theoretical Astrophysics, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; Theoretical Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USACenter for Theoretical Astrophysics, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USACenter for Theoretical Astrophysics, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; Theoretical Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USACenter for Theoretical Astrophysics, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USACenter for Theoretical Astrophysics, Los Alamos National Laboratory , Los Alamos, NM 87545, USA; Theoretical Division, Los Alamos National Laboratory , Los Alamos, NM 87545, USAStudying compact-star binaries and their mergers is integral to determining progenitors for observable transients. Today, compact-star mergers are typically studied via state-of-the-art computational fluid dynamics codes. One such numerical technique, smoothed particle hydrodynamics (SPH), is frequently chosen for its excellent mass, energy, and momentum conservation. The natural treatment of vacuum and the ability to represent highly irregular morphologies make SPH an excellent tool for the study of compact-star binaries and mergers. For many scenarios, including binary systems, the outcome of simulations is only as accurate as the initial conditions. For SPH, it is essential to ensure that the particles are distributed regularly, representing the initial density profile but without long-range correlations. Particle noise in the form of high-frequency local motion and low-frequency global dynamics must be damped out. Damping the latter can be as computationally intensive as the actual simulation. We discuss a new and straightforward relaxation method, halted-pendulum relaxation (HPR), to remove global oscillation modes of SPH particle configurations. In combination with effective external potentials representing gravitational and orbital forces, we show that HPR has an excellent performance in efficiently relaxing SPH particles to the desired density distribution and removing global oscillation modes. We compare the method to frequently used relaxation approaches and test it on a white dwarf binary model at its Roche-lobe overflow limit. We highlight the importance of our method in achieving accurate initial conditions and its effect on achieving circular orbits and realistic accretion rates when compared with other general relaxation methods.https://doi.org/10.3847/1538-4357/acd75aHydrodynamical simulationsAstronomical simulationsWhite dwarf starsCompact binary stars |
| spellingShingle | M. Alexander R. Kaltenborn Michael J. Falato Oleg Korobkin Irina Sagert Wesley P. Even Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data The Astrophysical Journal Hydrodynamical simulations Astronomical simulations White dwarf stars Compact binary stars |
| title | Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data |
| title_full | Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data |
| title_fullStr | Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data |
| title_full_unstemmed | Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data |
| title_short | Halted-pendulum Relaxation: Application to White Dwarf Binary Initial Data |
| title_sort | halted pendulum relaxation application to white dwarf binary initial data |
| topic | Hydrodynamical simulations Astronomical simulations White dwarf stars Compact binary stars |
| url | https://doi.org/10.3847/1538-4357/acd75a |
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