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---
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title: HiggsBounds
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permalink: /HiggsBounds/
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---
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[Category:Outputs](/Category:Outputs "wikilink") [Category:SPheno](/Category:SPheno "wikilink") With the discovery of the Higgs boson at the LHC and the precise measurements of its mass and couplings to other particles, a new era of high energy physics has started. Today, many SUSY models have not only be confronted with the exclusion limits from direct searches, but they have also to reproduce the Higgs properties correctly. The agreement with respect to the mass can be easily read off a spectrum file. For the rates this is usually not so easy. One can parametrize how ’SM-like’ the couplings of a particular scalar are by considering the ratio
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*r*<sup>*ϕ**X**Y*</sup> = (*c*<sub>*ϕ**X**Y*</sub><sup>*S**U**S**Y*</sup>/*c*<sub>*h**X**Y*</sub><sup>*S**M*</sup>)<sup>2</sup> .
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Here, *c*<sub>*ϕ**X**Y*</sub><sup>*S**U**S**Y*</sup> is the calculated coupling between a scalar *ϕ* and two SM particles *X* and *Y* for a particular parameter point in a particular model. This coupling is normalized to the SM expectation for the same interaction. Nowadays, all *r*<sup>*ϕ**X**Y*</sup> are constrained to be rather close to 1 if *ϕ* should be associated with the SM Higgs. SARAH uses the information which is already available from the calculation of the decays to obtain also values for *r*<sup>*ϕ**X**Y*</sup>. Of course, also here the *γ**Z* channel is missing and *r*<sup>*ϕ**γ**Z*</sup> is therefore put always to 0.
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<span>HiggsBounds</span> is a tool to test the neutral and charged Higgs sectors against the current exclusion bounds from the Higgs searches at the LEP, Tevatron and LHC experiments. The required input consists of the masses, width and branching ratios of the Higgs fields. In addition, it is either possible to provide full information about production cross sections in *e*<sup>+</sup>*e*<sup>−</sup> and *p**p* collisions, or to work with a set of effective couplings.
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<span>HiggsBounds</span> can be downloaded from
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http://projects.hepforge.org/higgsbound
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Although <span>HiggsBounds</span> supports a LesHouches interface, this functionality is restricted so far to at most 5 neutral Higgs fields, and therefore, we don’t use it. Instead, a SPheno module generated by SARAH can create all necessary input files needed for a run of <span>HiggsBounds</span> with effective couplings (option <span>whichinput=effC</span>). To write these file, the flag 76 in the block <span>SPhenoInfo</span> in the LesHouches input file has to be set to <span>1</span>.
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Block SPhenoInput #
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76 1 # Write files for HiggsBounds
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Unfortunately, we can not provide all information which can be used by <span>HiggsBounds</span> to check the constraints. So far, the effective couplings *H* → *γ**Z* and *H* → *g**g**Z* are not calculated by SPheno and therefore they are set to zero in the output. In addition, as already mentioned, the SPheno version created by SARAH does not include the calculations of *e*<sup>+</sup>*e*<sup>−</sup> cross sections. For this reason, also the LEP production cross section of charged Higgs fields is not available for SPheno and it sets this value also to 0 in the output. However, it is of course possible to calculate this cross section as well as all other cross sections needed for the options (<span>whichinput=hadr</span> or <span>whichinput=part</span>) of <span>HiggsBounds</span> using CalcHep , <span>Madgraph</span> or WHIZARD .
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The following files are created by SPheno
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- <span>MH_GammaTot.dat</span>:
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Masses and widths of all neutral Higgs fields
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- <span>MHplus_GammaTot.dat</span>:
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Masses and widths of all charged Higgs fields
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- <span>BR_H_NP.dat</span>:
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Branching ratios for neutral Higgs fields into invisible and other neutral Higgs fields.
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- <span>BR_Hplus.dat</span>:
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Branching ratios of charged Higgs fields into *c**s̄*, *c**b̄* and *τ**ν̄* final states
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- <span>BR_t.dat</span>:
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Branching ratios of top quark into bottom quark and a *W* boson or charged Higgs
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- <span>effC.dat</span>: effective couplings of neutral Higgs fields to *s**s̄*, *c**c̄*, *b**b̄*, *t**t̄*, *μ**μ̄*, *τ**τ̄*, *γ**γ*, *g**g*, *γ**Z*, *g**g**Z* as well as to all other neutral Higgs fields.
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- <span>LEP_HpHm_CS_ratios.dat</span>:
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LEP production cross section of charged Higgs. (set to zero, see above).
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To run <span>HiggsBounds</span> , use in the <span>HiggsBounds</span> directory
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> ./HiggsBounds LandH effC [NN] [NC] '[SPheno Directory]'
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where has to be replaced by the number of neutral Higgs particle, and by the number of the charged ones. For more information, see also the <span>HiggsBounds</span> manual. The results of the check are written to the file <span>HiggsBounds_results.dat</span> in the directory from which <span>HiggsBounds</span> has been called.
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See also
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-------- |
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\ No newline at end of file |