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LHC limits on the Higgs-portal WIMPs

LHC limits on the Higgs-portal WIMPs. arXiv: 1407.6882 in collaboration with M. Endo ( U.Tokyo ). Portal models to Hidden Sector. Consider another world where particles are SM singlets ( Hidden Sector ). The particles interact to our SM world through Gravity. DM ?. SM. Hidden. G.

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LHC limits on the Higgs-portal WIMPs

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  1. LHC limits on the Higgs-portal WIMPs arXiv: 1407.6882 in collaboration with M. Endo (U.Tokyo)

  2. Portal models to Hidden Sector Consider another world where particles are SM singlets (Hidden Sector). The particles interact to our SM world through Gravity. DM ? SM Hidden G Neutrino Portal Sterile neutrino Also, they may interact through… Dark Photon Vector Portal Axino-like particle AxionPortal Higgs invisible decay Higgs Portal In this talk, we discuss the Higgs-portal possibility.

  3. Constraints on Higgs-portal models • Relic abundance • Direct detection • Collider search Tight constraints on Higgs-portal “DM”. Still important to know to what extent LHC can explore the heavier Higgs-portal models. Heavy Higgs-portal WIMP search Need not to be the DM [Simone, Giudice, Strumia: 1402.6287]

  4. Collider search for Heavy Higgs-portal WIMP

  5. Higgs-portal models to be studied [A. Djouadi et al.1205.3169, S.Kanemura et al.1005.5651 ] Scalar Vector Anti-sym. Tensor [O.Cata, A. Ibarra: 1404.0432] are SM singlets. Fermionic hidden particle is not considered for simplicity. parity is assumed forandto ensure their stability. (SM singlet is stable without imposing parity by hand) after EWSB

  6. Cross section of WIMP-pair production We can express the WIMP pair production cross section as This is the basic formulae for our analysis.

  7. Experimental searches • VBF Higgs invisible decay • Mono-jet • Mono-Z

  8. Searches for Higgs invisible decay at the LHC Vector Boson Fusion (VBF) • 2ndlargest Higgs production process • Good S/B (large rapidity gap of 2 energetic forwarding jets) • BR_inv < 0.65 [CMS: 8TeV 19.5 fb^-1: 1404.1344] Z associated production (ZH) • Good S/B (Z-mass constraint, 2-lepton +missing) • Cross section is small (Useful at high luminosity) • BR_inv < 0.75 [ATLAS: 8TeV 20.3 fb^-1: 1402.3244] • BR_inv < 0.81 [CMS: 8TeV 19.5 fb^-1: 1404.1344]

  9. Mono-X searches Mono-X searches (X +missing pT) are also sensitive to Higgs-portal models. Mono-jet Mono-Z Mono-lepton Mono-photon Mono-top Mono-Higgs etc … • Large Cross section • Main mono-X mode so far • S/B is not good • Gluon-fusion Higgs production • Same topology as ZH • for Higgs-portal model

  10. VBF analysis (CMS , 1404.1344) We calculate under the following cuts (w/ MCFM-6.8): Compare to the upper bound on the signal events. 95% CL upper bound

  11. 8 TeV LHC constraints

  12. Limits for the Heavy Higgs-portal WIMPs Tensor Vector Data : BG VBF 390 : 332(58) Mono-jet 1772 : 1931(131) Mono-Z 45 : 52(18) Scalar

  13. 14 TeV LHC prospects

  14. How to perform (rough) projection We need to know and to estimate the 14 TeV constraints on . is estimated by theoretical calculations with experimental cuts. is roughly estimated with the following assumptions: increases due to PDF (luminosity ratio) and integrated luminosity Relative does not improve Relative reduces as . 95% CL (simple Gaussian)

  15. Sensitivity Summary (Mono-j, VBF, Mono-Z) * Rough Estimate Tensor MJ MZ VBF MJ MJ MZ MZ VBF VBF MJ MZ VBF

  16. Summary LHC constraints on the Heavy Higgs-portal WIMP have been Studied. 8 TeV LHC results can access the Higgs-portal couplings below 1 for the vector and tensor case. Scalar coupling limit is very weak. 14 TeV LHC can reach at O(0.1) couplings for vector and tensor case. The scalar coupling below O(1) will be remained unexplored. VBF channel already shows good performance in 8 TeV LHC, replacing the mono-jet channel. ZH, Mono-Zchannel will also be a important channel in 14 TeV LHC.

  17. Backup Slides

  18. Mono-jet analysis (CMS-PAS-EXO-12-048 ) We calculate under the following cuts (w/ MCFM-6.8): giving the most stringent limit • Taming the infinite top mass effects • Avoiding large region (* 2nd jet with pT > 30 GeV (from NLO real emission) is not vetoed, due to technical reason. )

  19. Mono-jet analysis We would like to evaluate the cross section at least NLO QCD order. However, NLO cross sections are only known in limit. [R.V.Handler et al. 1206.0157] K-factor K-factor LO We approximate the NLO cross section as [L.Altenkamp et al. 1211.5015]

  20. Mono-Z analysis (ATLAS , 1404.0051) We calculate under the following cuts (w/ HAWK-2.0): giving the most stringent limit

  21. Mono-jet channel: 14 TeV LHC Cross Sections at 14 TeV Cx < 1 (100 1/fb) Cx < 0.2 (100 1/fb)

  22. Mono-Z channel: 14 TeV LHC Cross Sections at 14 TeV

  23. VBF and ZH channels 95% Upper bounds on the Higgs inv. decay ratio at mH = 125 GeV [5] ATLAS, 1402.3244 [6] CMS, 1404.1344 [16] D.Gosh et al., 1211.7015 [17] ATL-PHYS-PUB-2013-014 [18] Snowmass, 1309.7925 Cut-based Profile-based The VBF bound will be improved by a factor of 4 at mH = 125 GeV. If this level of improvement holds for any mH, the Upper bound on improves a factor of 4. The Upper bound on improves a factor of 2. The Upper bound on will be improved by a factor of 1.5 ~ 2(300 1/fb) and 2 ~ 3.5 (3,000 1/fb). The ZH bound will be improved by a factor of 2 ~ 4 (300 1/fb) and 4 ~ 12 (3,000 1/fb).

  24. Higgs production Cross Sections Gluon-fusion VBF ZH WH

  25. How to estimate

  26. archive

  27. We will investigate the constraints of the LHC invisible searches on Heavier Higgs-portal WIMP models.

  28. Mono-X searches Mono-X searches (X +missing pT) are also sensitive to Higgs-portal models. Mono-jet Mono-Z Mono-lepton • S/B is good • Cross section is small • Useful for high luminosity • WH production • Same topology as ZH • for Higgs-portal model • Large Cross section • Main mono-X mode so far • S/B is not good • Gluon-fusion Higgs production

  29. Direct searches for Higgs invisible decay at the LHC SM prediction: Sizable BR_inv is an evidence of BSM models! Vector Boson Fusion (VBF) • 2ndlargest Higgs production process • Good S/B (large rapidity gap of 2 energetic forwarding jets) • BR_inv < 0.65 [CMS: 8TeV 19.5 fb^-1: 1404.1344] Z associated production (ZH) • Good S/B (Z-mass constraint, 2-lepton +missing) • Cross section is small • Useful for high luminosity • BR_inv < 0.75 [ATLAS: 8TeV 20.3 fb^-1: 1402.3244] • BR_inv < 0.81 [CMS: 8TeV 19.5 fb^-1: 1404.1344]

  30. Mono-jet Sensitivity * Rough Estimate Tensor

  31. Sensitivity Summary (Mono-j, VBF, Mono-Z) * Rough Estimate

  32. How to perform (theorist’s) projection We need to know and to estimate the 14 TeV constraints on . is estimated by theoretical calculations with experimental cuts. is roughly estimated with the following assumptions: 95% CL (simple Gaussian) does not improve reduces as increases due to PDF (luminosity ratio) and integrated luminosity 8TeV data

  33. How to perform (theorist’s) projection We need to know and to estimate the 14 TeV constraints on . is estimated by theoretical calculations with cuts. is roughly estimated with the following assumptions:

  34. Searches for Higgs invisible decay at the LHC SM prediction: Sizable BR_inv is an evidence of BSM models Vector Boson Fusion (VBF) • 2ndlargest Higgs production process • Good S/B (large rapidity gap of 2 energetic forwarding jets) • BR_inv < 0.65 [CMS: 8TeV 19.5 fb^-1: 1404.1344] Z associated production (ZH) • Good S/B (Z-mass constraint, 2-lepton +missing) • Cross section is small • Useful for high luminosity • BR_inv < 0.75 [ATLAS: 8TeV 20.3 fb^-1: 1402.3244] • BR_inv < 0.81 [CMS: 8TeV 19.5 fb^-1: 1404.1344]

  35. Direct searches for Higgs invisible decay at the LHC Upper bounds on the BR_inv have been obtained using invisible decay modes Vector Boson Fusion (VBF) • 2ndlargest Higgs production process • Good S/B (large rapidity gap of 2 energetic forwarding jets) • Useful for high luminosity • BR_inv < 0.65 [CMS: 8TeV 19.5 fb^-1: 1404.1344] Z associated production (ZH) • Good S/B (Z-mass constraint, 2-lepton +missing) • Cross section is small • Useful for high luminosity • BR_inv < 0.75 [ATLAS: 8TeV 20.3 fb^-1: 1402.3244] • BR_inv < 0.81 [CMS: 8TeV 19.5 fb^-1: 1404.1344]

  36. Constraints on Higgs-portal DM models • Relic abundance • Direct detection • Collider search Tight constraints on Higgs-portal DM. Collider search is powerful, but Caveats: Small abundance direct detection Heavy Higgs inv. decay Heavy Higgs-portal WIMP [Simone, Giudice, Strumia: 1402.6287]

  37. Constraints on Higgs-portal DM models • Relic abundance • Direct detection • Collider search There are severe constraints on the Higgs-portal DM models. However, this is applicable only if the hidden particle is the dominant component of the DM. Not rule out less abundant components (Higgs-portal WIMPs) at the same level. Collider WIMP searches is the right way for such possibilities.

  38. Interpretation for Higgs-portal WIMPs How about for Heavier Higgs-portal DMs? No explicit analysis. We will try to re-interpret the direct Higgs invisible decay and mono-X limits for Heavier DM case.

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