Mind the gap: The discrepancy between simulation and reality drives interpretations of the Galactic Center Excess by Sascha Caron et al. on Monday 21 November

The origin of the so-called Galactic Center Excess in GeV gamma rays has been

debated for more than 10 years. What makes this excess so interesting is the

possibility of interpreting it as additional radiation consistent with that

expected from dark matter annihilation. Alternatively, the excess could come

from undetected point sources. In this work, we examine the following

questions: Since the majority of the previously reported interpretations of

this excess are highly dependent on the simulation, how does the model used for

the simulation affect the interpretations? Are such uncertainties taken into

account? When different models lead to different conclusions, there may be a

general gap between these simulations and reality that influences our

conclusions. To investigate these questions, we build an ultra-fast and

powerful inference pipeline based on convolutional deep ensemble networks and

test the interpretations with a wide range of different models to simulate the

excess. We find that our conclusions (dark matter or not) strongly depend on

the type of simulation and that this is not revealed by systematic

uncertainties. Furthermore, we measure whether reality lies in the simulation

parameter space and conclude that there is a gap to reality in all simulated

models. Our approach offers a means to assess the severity of the reality gap

in future works. Our work questions the validity of conclusions (dark matter)

drawn about the GCE in other works: Has the reality gap been closed and at the

same time is the model correct?

arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.09796v1