We compare the performance of energy-based and entropy-conserving schemes for modeling nonthermal energy components, such as unresolved turbulence and cosmic rays, using idealized fluid dynamics tests and isolated galaxy simulations. While both methods are aimed to model advection and adiabatic compression or expansion of different energy components, the energy-based scheme numerically solves the nonconservative equation for the energy density evolution, while the entropy-conserving scheme uses a conservative equation for modified entropy. Using the standard shock tube and Zel’dovich pancake tests, we show that the energy-based scheme results in a spurious generation of nonthermal energy on shocks, while the entropy-conserving method evolves the energy adiabatically to machine precision. We also show that, in simulations of an isolated
Tests of the standard model of particle physics should be carried out over the widest possible range of energies. Here we present our plans and progress for an atomic parity non-conservation experiment using the heaviest alkali, francium (
- NSF-PAR ID:
- 10367652
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Quantum Science and Technology
- Volume:
- 7
- Issue:
- 2
- ISSN:
- 2058-9565
- Page Range / eLocation ID:
- Article No. 024001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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