B Is Dark Matter in the 100GeV range

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Recent observations of galactic cosmic rays have shown significant deviations from standard models, particularly in the 1-500 GeV energy range. These anomalies challenge traditional explanations of cosmic ray production in supernova remnants and suggest the need for new physics in particle acceleration. A notable 20-30% excess in the positron ratio remains unexplained, potentially indicating contributions from dark matter decay or pulsars. The discussion highlights that while dark matter is not definitively expected in the 100 GeV range, it aligns with various WIMP models, particularly those involving supersymmetry. The urgency for solid energy range findings is emphasized, especially as some detection efforts face closure.
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arXiv:1703.05772 [pdf, other]

Newly-Discovered Anomalies in Galactic Cosmic Rays: Time for Exotic Scenarios?
Mikhail Malkov
Comments: Cosmic Rays beyond the Standard Model, San Vito, 2016, this http URL, conference paper
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

Recent observations of galactic cosmic rays (CR) in the 1-500 GeV energy range have revealed striking deviations from what deemed "standard." The anomalies cut across hadronic and leptonic CRs. I discuss findings that challenge physical mechanisms long held responsible for the CR production in galactic supernova remnants (SNR). I also consider some new physics of particle acceleration in SNR shocks that is not part of conventional models but may explain the anomalies. However, a possible 20-30\% excess remains unaccounted for in the e+/e+ ratio over the range of a few 100 GeV. If not explained by future models, it suggests an additional source of positrons such as a dark matter decay/annihilation or pulsar contribution. Earlier efforts to explain both the e+/e− and p/He anomalies with the "standard" models by adjusting the SNR environmental parameters and multiple sources are critically assessed.

Just as the title says, Is Dark Mater expected to be in the 100GeV range?
Thanks for replies.
 
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I don't know about 'expected', but it's certainly in the prime mass range for a variety of WIMP proposals. SUSY models in particular expect a mass in this range.

Section 3 of this paper has a nice graphic that shows the current status of the theoretical predictions (as well as direct dark matter searches):
https://arxiv.org/pdf/1406.5200.pdf
 
Thanks for reply Chalnoth, I hope that the Dark Matter particle is found soon as it seems some detectors will be closing down soon, I guess that a solid energy range would accelerate research, but how are we going to get a 3 sigma result from all the noise?
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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