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DOE OSTI · 1980118

Simulating magnetized neutron stars with discontinuous Galerkin methods

Deppe, Nils·Hébert, François·Kidder, Lawrence E.·Throwe, William·Anantpurkar, Isha·Armaza, Cristóbal·Bonilla, Gabriel S.·Boyle, Michael·Chaudhary, Himanshu·Duez, Matthew D.·Vu, Nils L.·Foucart, Francois·Giesler, Matthew·Guo, Jason S.·Kim, Yoonsoo·Kumar, Prayush·Legred, Isaac·Li, Dongjun·Lovelace, Geoffrey·Ma, Sizheng·Macedo, Alexandra·Melchor, Denyz·Morales, Marlo·Moxon, Jordan·Nelli, Kyle C.·O’Shea, Eamonn·Pfeiffer, Harald P.·Ramirez, Teresita·Rüter, Hannes R.·Sanchez, Jennifer·Scheel, Mark A.·Thomas, Sierra·Vieira, Daniel·Wittek, Nikolas A.·Wlodarczyk, Tom·Teukolsky, Saul A.
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Abstract

Discontinuous Galerkin methods are popular because they can achieve high order where the solution is smooth, because they can capture shocks while needing only nearest-neighbor communication, and because they are relatively easy to formulate on complex meshes. We perform a detailed comparison of various limiting strategies presented in the literature applied to the equations of general relativistic magnetohydrodynamics. We compare the standard minmod /ΛΠ N limiter, the hierarchical limiter of Krivodonova, the simple WENO limiter, the HWENO limiter, and a discontinuous Galerkin-finite-difference hybrid method. The ultimate goal is to understand what limiting strategies are able to robustly simulate magnetized Tolman-Oppenheimer-Volkoff stars without any fine-tuning of parameters. Among the limiters explored in the paper, the only limiting strategy we can endorse is a discontinuous Galerkin-finite-difference hybrid method.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS79 ASTRONOMY AND ASTROPHYSICSgeneral relativitynumerical relativity

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Deppe, Nils, Hébert, François, Kidder, Lawrence E., Throwe, William, Anantpurkar, Isha, Armaza, Cristóbal, Bonilla, Gabriel S., Boyle, Michael, Chaudhary, Himanshu, Duez, Matthew D., Vu, Nils L., Foucart, Francois, Giesler, Matthew, Guo, Jason S., Kim, Yoonsoo, Kumar, Prayush, Legred, Isaac, Li, Dongjun, Lovelace, Geoffrey, Ma, Sizheng, Macedo, Alexandra, Melchor, Denyz, Morales, Marlo, Moxon, Jordan, Nelli, Kyle C., O’Shea, Eamonn, Pfeiffer, Harald P., Ramirez, Teresita, Rüter, Hannes R., Sanchez, Jennifer, Scheel, Mark A., Thomas, Sierra, Vieira, Daniel, Wittek, Nikolas A., Wlodarczyk, Tom, Teukolsky, Saul A.. 2022-06-27. Simulating magnetized neutron stars with discontinuous Galerkin methods. https://doi.org/10.1103/physrevd.105.123031

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