Likelihood analysis of the minimal AMSB model

Journal Article · 27 April 2017 · European Physical Journal. C, Particles and Fields

DOI: https://doi.org/10.1140/epjc/s10052-017-4810-0 · OSTI ID:1353303

Bagnaschi, E.; Borsato, M. ; Sakurai, K.; Buchmueller, O.; Cavanaugh, R.; Chobanova, V.; Citron, M.; Costa, J. C.; De Roeck, A.; Dolan, M. J.; Ellis, J. R.; Flächer, H.; Heinemeyer, S.; Isidori, G.; Lucio, M.; Luo, F.; Santos, D. Martínez; Olive, K. A.; Richards, A.; Weiglein, G.

We perform a likelihood analysis of the minimal Anomaly-Mediated Supersymmetry Breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that a wino-like or a Higgsino-like neutralino LSP, $$m_{\tilde \chi^0_{1}}$$, may provide the cold dark matter (DM) with similar likelihood. The upper limit on the DM density from Planck and other experiments enforces $$m_{\tilde \chi^0_{1}} \lesssim 3~TeV$$ after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the $$\tilde \chi_0^1$$, the measured value of the Higgs mass favours a limited range of $$\tan \beta \sim 5$$ (or for $$\mu > 0$$, $$\tan \beta \sim 45$$) but the scalar mass $$m_0$$ is poorly constrained. In the wino-LSP case, $$m_{3/2}$$ is constrained to about $900~TeV$ and $${m_{\tilde \chi^0_{1}}}$$ to $$2.9\pm0.1~TeV$$, whereas in the Higgsino-LSP case $$m_{3/2}$$ has just a lower limit $$\gtrsim 650TeV$$ ($$\gtrsim 480TeV$$) and $$m_{\tilde \chi^0_{1}}$$ is constrained to $$1.12 ~(1.13) \pm0.02~TeV$$ in the $$\mu>0$$ ($$\mu<0$$) scenario. In neither case can the anomalous magnetic moment of the muon, $${(g-2)_\mu}$$, be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, {though there} are some prospects for direct DM detection. On the other hand, if the $${m_{\tilde \chi^0_{1}}}$$ contributes only a fraction of the cold DM density, {future LHC $$E_T$$-based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant}, and interference effects enable $${\rm BR}(B_{s, d} \to \mu^+\mu^-)$$ to agree with the data better than in the SM in the case of wino-like DM with $$\mu > 0$$.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 1353303
• Alternate ID(s): OSTI ID: 1354877
• Report Number(s): CERN-PH-TH-2016-220; arXiv:1612.05210; FERMILAB-PUB-16-502-CMS; DESY-16-155; KCL-PH-TH-2016-58; CERN-TH-2016-220; IFT-UAM-CSIC-16-112; IPMU-16-0157; FTPI-MINN-16-30; UMN-TH-3610-16; IPPP-16-104; 268; PII: 4810
• Journal Information: European Physical Journal. C, Particles and Fields, Journal Name: European Physical Journal. C, Particles and Fields Vol. 77 Journal Issue: 4; ISSN 1434-6044
• Publisher: SpringerCopyright Statement
• Country of Publication: Germany
• Language: English