Hyped Signal of Decaying Dark Matter becomes phantom signal in Updated Analysis

What is dark matter/energy anyway? A fig leaf of the imagination? Like the infamous terra incognita?

"In 2014, astrophysicists caught a glimpse of what they thought was their white whale: evidence of the nature of the mysterious and elusive dark matter that makes up 85 percent of the universe’s material. They spotted X-ray activity thought to result from decaying dark matter, as typical matter would not have been able to produce such a signal. With this exciting discovery, a window seemed to have finally opened into dark matter’s secrets.

The problem, however, is that according to new research, the signal (called the 3.5 keV line) probably never existed in the first place. By re-creating the original studies’ analysis techniques and applying new, more comprehensive tools, a team of astrophysicists concluded that the 3.5 keV line originally arose from flaws in data analysis. The team reports their findings in the April 1 issue of The Astrophysical Journal. ..."

From the abstract:

"The 3.5 keV line is a purported emission line observed in galaxies, galaxy clusters, and the Milky Way whose origin is inconsistent with known atomic transitions and has previously been suggested to arise from dark matter decay. We systematically reexamine the bulk of the evidence for the 3.5 keV line, attempting to reproduce six previous analyses that found evidence for the line. We only reproduce one of the analyses; in the other five, we find no significant evidence for a 3.5 keV line when following the described analysis procedures on the original data sets. For example, previous results claimed 4σ evidence for a 3.5 keV line from the Perseus cluster; we dispute this claim, finding no evidence for a 3.5 keV line. We find evidence for background mismodeling in multiple analyses. We show that analyzing these data in narrower energy windows diminishes the effects of mismodeling but returns no evidence for a 3.5 keV line. We conclude that there is little robust evidence for the existence of the 3.5 keV line. Some of the discrepancy of our results from those of the original works may be due to the earlier reliance on local optimizers, which we demonstrate can lead to incorrect results. For ease of reproducibility, all code and data are publicly available."

Hyped Signal of Decaying Dark Matter Vanishes in Updated Analysis "In 2014, scientists observed X-ray activity from distant galaxies that was thought to be the first evidence of dark matter decay — a landmark discovery that could significantly advance efforts to characterize this puzzling substance. However, a new study from the Flatiron Institute and collaborators suggests that imperfect analysis methods used to detect the activity — called the 3.5 keV line — likely produced a phantom signal."

Was There a 3.5 keV Line? (open access)

Two views of the Perseus galaxy cluster — one of the original sites thought to exhibit a 3.5 keV line — captured by the XMM-Newton and Chandra telescopes