%0 Generic %1 asencio2023gordo %A Asencio, E. %A Banik, I. %A Kroupa, P. %D 2023 %K tifr %T The El Gordo galaxy cluster challenges ŁambdaCDM for any plausible collision velocity %U http://arxiv.org/abs/2308.00744 %X El Gordo (ACT-CL J0102-4915) is an extraordinarily large and bright galaxy cluster collision. In a previous study, we found that El Gordo is in $6.2\sigma$ tension with the $Łambda$CDM standard model when assuming the nominal mass and infall velocity values from the hydrodynamical simulations of Zhang et al. ($M_200 = 3.2 10^15 M_ødot$ and $V_infall = 2500~km~s^-1$, respectively). The recent weak lensing study of Kim et al. showed that the mass of El Gordo is actually $2.13^+0.25_-0.23 10^15 M_ødot$. Here we explore the level of tension between El Gordo and $Łambda$CDM for the new mass estimate, assuming several $V_infall$ values. We find that in order to reduce the tension below the $5\sigma$ level, the El Gordo subclusters should have $V_infall < 2300~km~s^-1$ ($V_infall < 1800~km~s^-1$ when considering the combined tension with the Bullet Cluster). To the best of our knowledge, the El Gordo hydrodynamical simulations conducted so far require $V_infall 2500~km~s^-1$ to simultaneously reproduce its morphology and its high X-ray luminosity and temperature. We therefore conclude that El Gordo still poses a significant challenge to $Łambda$CDM cosmology. Whether the properties of El Gordo can be reconciled with a lower $V_infall$ should be tested with new hydrodynamical simulations that explore different configurations of the interaction.

@misc{asencio2023gordo, abstract = {El Gordo (ACT-CL J0102-4915) is an extraordinarily large and bright galaxy cluster collision. In a previous study, we found that El Gordo is in $6.2\sigma$ tension with the $\Lambda$CDM standard model when assuming the nominal mass and infall velocity values from the hydrodynamical simulations of Zhang et al. ($M_{200} = 3.2 \times 10^{15} M_{\odot}$ and $V_{\textrm{infall}} = 2500~\textrm{km~s}^{-1}$, respectively). The recent weak lensing study of Kim et al. showed that the mass of El Gordo is actually $2.13^{+0.25}_{-0.23} \times 10^{15} M_{\odot}$. Here we explore the level of tension between El Gordo and $\Lambda$CDM for the new mass estimate, assuming several $V_{\textrm{infall}}$ values. We find that in order to reduce the tension below the $5\sigma$ level, the El Gordo subclusters should have $V_{\textrm{infall}} < 2300~\textrm{km~s}^{-1}$ ($V_{\textrm{infall}} < 1800~\textrm{km~s}^{-1}$ when considering the combined tension with the Bullet Cluster). To the best of our knowledge, the El Gordo hydrodynamical simulations conducted so far require $V_{\textrm{infall}} \geq 2500~\textrm{km~s}^{-1}$ to simultaneously reproduce its morphology and its high X-ray luminosity and temperature. We therefore conclude that El Gordo still poses a significant challenge to $\Lambda$CDM cosmology. Whether the properties of El Gordo can be reconciled with a lower $V_{\textrm{infall}}$ should be tested with new hydrodynamical simulations that explore different configurations of the interaction.}, added-at = {2023-08-03T06:03:22.000+0200}, author = {Asencio, E. and Banik, I. and Kroupa, P.}, biburl = {https://www.bibsonomy.org/bibtex/28f02aceb66f7d2dc43726514bcc90bd7/citekhatri}, description = {The El Gordo galaxy cluster challenges {\Lambda}CDM for any plausible collision velocity}, interhash = {f0e56a693e9aa72d0c3314f29a6cc8cc}, intrahash = {8f02aceb66f7d2dc43726514bcc90bd7}, keywords = {tifr}, note = {cite arxiv:2308.00744Comment: 8 pages, 1 figure. Accepted for publication in The Astrophysical Journal in this form}, timestamp = {2023-08-03T06:03:22.000+0200}, title = {The El Gordo galaxy cluster challenges {\Lambda}CDM for any plausible collision velocity}, url = {http://arxiv.org/abs/2308.00744}, year = 2023 }