I Is El Gordo's Collision Velocity Challenging ΛCDM?

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El Gordo's collision velocity continues to present challenges to the ΛCDM model despite a revised mass estimate that slightly reduces the tension. Detailed simulations indicate that the observed characteristics of El Gordo cannot be reconciled with a significantly slower collision velocity, which is more consistent with ΛCDM predictions. The ongoing debate highlights the need for further investigation into the implications of such high-velocity collisions on cosmic structure formation. Previous studies, including those on the Bullet Cluster and MOND, provide additional context to the discussion. The findings suggest that El Gordo remains a critical case for understanding the limitations of the ΛCDM framework.
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Data from Chandra X ray telescope, show ΛCDM tension with El Gordo large galaxy cluster collision.
The article is here https://phys.org/news/2023-09-titanic-galaxy-cluster-collision-early.html

"The results of our previous study were questioned by some scientists once an updated mass estimate for El Gordo was published and came in slightly lower. This does reduce the tension with ΛCDM, but it is still highly significant for any plausible collision velocity. Hundreds of detailed simulations show that El Gordo cannot look like the photos with a much slower collision velocity that could plausibly arise in ΛCDM."

Paper here https://iopscience.iop.org/article/10.3847/1538-4357/ace62a
Previous paper here from 2020 with a discussion of the bullet cluster and MOND (4.3)

Previous data from Webb on the same issue. https://iopscience.iop.org/article/10.3847/2041-8213/ac9a50

Info on Chandra https://en.m.wikipedia.org/wiki/Chandra_X-ray_Observatory
 
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