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Higgs Mass Predictions?

  1. Nov 29, 2006 #1
    Can anyone tell me what the experts expect the Higgs mass to be in various well discussed models?
    i.e. SM
    little Higgs
    split supersymmetry

    Or do they all just predict 114-1000 GeV?

    I think MSSM predicts less than 125 or 130 max.

    I have heard rumors that SM predicts near 175,
    and also that it predicts 85 plus unspecified corrections.

    The others I only know broad ranges or weasel words.

    Can anyone help me out?
    Pointers to actual sources for any significant predictions would be appreciated.
    Jim Graber
  2. jcsd
  3. Nov 29, 2006 #2
    SM: no prediction, but electroweak precision fits indicate it is lighter than 200GeV. LEP searches indicate it is heavier than 114GeV

    MSSM: lower limit as above (there are a few 'edge of parameter space' scenarios where it could be as light as about 97GeV though). Upper limit about 130GeV

    NMSSM: upper limit about 140GeV, no lower limit.

    little Higgs is pretty much already ruled out. The allowed scenarios are getting increasingly wacky.

    Split susy: no idea - why would anyone care?

    This talk might be useful to you:
    (slide 20 has the 'rumors' you were talking about)
  4. Dec 3, 2006 #3


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    Speaking of the nMssM do you happen to know which processes combine to give the unitarity bound on the upper limit?
  5. Dec 4, 2006 #4
    It isn't a unitarity bound. It is a bound coming directly from the form of the mass matrix. The smallest eigenvalue of a matrix is always less than its smallest diagonal entry.
  6. Dec 4, 2006 #5


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    IC, thats interesting (I have hopelessly little knowledge in the nMssM phenomonology other than just the general scheme).. What does the 140 GEV diagonal eigenstate correspond too and how are they able to get the number?
  7. Dec 4, 2006 #6
    It is the usual bound from the MSSM plus an extra term that comes from the singlet coupling to the Higgs.

    You might find this paper useful:

    Eq.26 is the appropriate term.

    Actually, the upper bound on lambda is unitarity, so I suppose it is indirectly a unitarity bound after all.
    Last edited: Dec 4, 2006
  8. Dec 5, 2006 #7


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    Thanks, makes a lot of sense now and a good paper as well.
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