Empirical test for relativistic kinetic theories based on the Sunyaev-Zel'dovich effect
arXiv:2009.04633 · doi:10.3847/1538-4357/abb6f6
Abstract
We propose a new method to determine the electron velocity (EV) distribution function in the intracluster gas (ICG) in clusters of galaxies based on the frequency dependence of the Sunyaev-Zel'dovich (SZ) effect. It is generally accepted that the relativistic equilibrium EV distribution is the one suggested by Juttner. However, there is an ongoing debate on the foundation of relativistic kinetic theory, and other distributions have also been proposed. The mildly relativistic intracluster gas (ICG) provides a unique laboratory to test relativistic kinetic theories. We carried out Monte Carlo simulations to generate SZ signal from a single-temperature gas assuming the Juttner EV distribution assuming a few per cent errors. We fitted SZ models based on non-relativistic Maxwellian, and its two relativistic generalizations, the Juttner and modified Juttner distributions. We found that a 1% error in the SZ signal is sufficient to distinguish between these distributions with high significance based on their different best-fit temperatures. However, in any LOS in a cluster, the ICG contains a range of temperatures. Using our N-body/hydrodynamical simulation of a merging galaxy cluster and assuming a 1% error in the SZ measurements in a LOS through a bow shock, we find that it is possible to distinguish between Juttner and modified Juttner distributions with high significance. Our results suggest that deriving ICG temperatures from fitting to SZ data assuming different EV distribution functions and comparing them to the temperature in the same cluster obtained using other observations would enable us to distinguish between the different distributions.11 pages, 8 figures, and 1 table, accepted for publication in the Astrophysical Journal
11 pages, 8 figures, and 1 table, accepted for publication in the Astrophysical Journal
References in corpus (15)
- A direct empirical proof of the existence of dark matter
- A Direct Multigrid Poisson Solver for Oct-Tree Adaptive Meshes
- Thermal equilibrium and statistical thermometers in special relativity
- The upGREAT dual frequency heterodyne arrays for SOFIA
- Relative entropy, Haar measures and relativistic canonical velocity distributions
- Covariant Equilibrium Statistical Mechanics
- A Hydrodynamical Solution for the "Twin-Tailed" Colliding Galaxy Cluster "El Gordo"
- Statistical thermodynamics of a two dimensional relativistic gas
- Towards a relativistic statistical theory
- Statistical kinetic treatment of relativistic binary collisions
- Analysis and Interpretation of Hard X-ray Emission from the Bullet Cluster (1E0657-56), the Most Distant Cluster of Galaxies Observed by RXTE
- One-dimensional nonrelativistic and relativistic Brownian motions: A microscopic collision model
- Pressure profiles of distant galaxy clusters in the Planck catalog
- An analysis of electron distributions in galaxy clusters by means of the flux ratio of iron lines FeXXV and XXVI
- Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZ