## Friday, May 10, 2019 ... //

### Pheno papers on $96\GeV$ Higgs, trilepton excess, and $60\GeV$ dark matter

I want to mention two new hep-ph papers about supersymmetry-like anomalies seen by the accelerators. In the paper

An N2HDM Solution for the possible $96\GeV$ Excess,
B+C+Heinemeyer discuss some detailed models for the apparent weak signals indicating a new Higgs boson of mass around $96\GeV$. Recall that the only well-established Higgs boson has the mass of $125\GeV$.

Concerning the $96\GeV$ little brother, the CMS has seen an excess in the diphoton channel; and decades ago, LEP has seen an excess in the bottom quark pair channel. Heinemeyer and friends say that these excesses may be explained by a two-Higgs model with an extra Higgs singlet. Is that surprising at all? There seems to be a lot of freedom to accommodate two independent excesses, right?

At any rate, concerning supersymmetric models, the NMSSM – next-to-minimal supersymmetric standard model – and its extension, µνSSM seem like aesthetically pleasing completions of the two-Higgs-plus-a-singlet models. In the model with the two Greek letters, the singlet is interpreted as a right-handed neutrino superfield and the seesaw mechanism is incorporated. These models look OK for the excesses – there are other reasons to prefer NMSSM over MSSM. But they're also less constrained and predictive than the MSSM, so I think the good news isn't remarkably victorious.

Another paper on the excesses is
The Return of the WIMP: Missing Energy Signals and the Galactic Center Excess
by Carena+Osborne+Shah+Wagner. They promote a model with the dark matter of mass $m_\chi = 60\GeV$ and its justification by anomalies that exist out there.

The dark matter of that mass would be the lightest neutralino. It could naturally agree with the 3-sigma trilepton ATLAS excess (and a confirmation by GAMBIT), the gamma ray excess at the center of our galaxy seen by Fermi-LAT, as well as the antiproton excess observed by AMS-02.

In their model, the LSP is a bino-like neutralino and another, wino-like neutralino should exist with the mass of $160\GeV$. $\tan\beta$ should be greater than ten. This paper may be viewed as a counter-argument against the recent efforts to claim that the central galactic gamma-ray excess was "due to some boring pulsars" only.

At any rate, dark matter of mass $60\GeV$ within supersymmetry is still plausible and somewhat recommended by some observations, much like the NMSSM-like new Higgs of mass $96\GeV$. I can't tell you the probability that these particles exist – it depends on lots of priors and methodology – but I am sure that it is just wrong and prejudiced to behave as if these probabilities were zero.