Cosmological constraints on the gas depletion factor in galaxy clusters
| Autor: | Holanda, R. F. L., Busti, V. C., Gonzalez, J. E., Andrade-Santos, F., Alcaniz, J. S. |
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| Rok vydání: | 2017 |
| Předmět: | |
| Zdroj: | JCAP12(2017)016 |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1088/1475-7516/2017/12/016 |
| Popis: | The evolution of the X-ray emitting gas mass fraction ($f_{gas}$) in massive galaxy clusters can be used as an independent cosmological tool to probe the expansion history of the Universe. Its use, however, depends upon a crucial quantity, i.e., the depletion factor $\gamma$, which corresponds to the ratio by which $f_{gas}$ is depleted with respect to the universal baryonic mean. This quantity is not directly observed and hydrodynamical simulations performed in a specific cosmological model (e.g., a flat $\Lambda$CDM cosmology) have been used to calibrate it. In this work, we obtain for the first time self-consistent observational constraints on the gas depletion factor combining 40 X-ray emitting gas mass fraction measurements and luminosity distance measurements from type Ia supernovae. Using Gaussian Processes to reconstruct a possible redshift evolution of $\gamma$, we find no evidence for such evolution, which confirms the current results from hydrodynamical simulations. Moreover, our constraints on $\gamma$ can be seen as a data prior for cosmological analyses on different cosmological models. The current measurements are systematic limited, so future improvements will depend heavily on a better mass calibration of galaxy clusters and their measured density profiles. Comment: 7 pages, 2 figure, 1 table, JCAP Accepted |
| Databáze: | arXiv |
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