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Title: Likelihood Analysis of the Minimal AMSB Model

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 $$\mu > 0$$.
ORCiD logo [1] ; ORCiD logo [2] ;  [3] ;  [4] ;  [5] ;  [2] ;  [4] ;  [4] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] ;  [2] ;  [12] ;  [2] ;  [13] ;  [4] ;  [4]
  1. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  2. Santiago de Compostela Univ. (Spain)
  3. Univ. of Warsaw (Poland); Univ. of Durham (United Kingdom)
  4. Imperial College, London (United Kingdom)
  5. Univ. of Illinois, Chicago, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  6. Antwerp Univ. (Belgium); European Organization for Nuclear Research (CERN), Geneva (Switzerland)
  7. Univ. of Melbourne (Australia)
  8. European Organization for Nuclear Research (CERN), Geneva (Switzerland); King's College London (United Kingdom)
  9. Bristol Univ. (United Kingdom)
  10. Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain)
  11. Univ. of Zurich (Switzerland)
  12. Univ. of Tokyo (Japan)
  13. Univ. of Minnesota, Minneapolis, MN (United States)
Publication Date:
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
Journal ID: ISSN 1434-6044; 1504084
Grant/Contract Number:
Published Article
Journal Name:
European Physical Journal. C, Particles and Fields
Additional Journal Information:
Journal Volume: C77; Journal Issue: 4; Journal ID: ISSN 1434-6044
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1354877