This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
2015:groups:higgs:morehiggs:scalartt [2015/06/12 00:46] ken.mimasu |
2015:groups:higgs:morehiggs:scalartt [2015/06/18 14:51] (current) ken.mimasu |
||
---|---|---|---|
Line 1: | Line 1: | ||
**Responsible:** Ken Mimasu | **Responsible:** Ken Mimasu | ||
- | **Members:** Jose Mi No, Chris Pollard, Sanjoy Biswas, Adam Falkowski | + | **Members:** Jose Mi No, Chris Pollard, Sanjoy Biswas, Adam Falkowski, Aurelio Juste, Andrey Katz, Aram Apyan |
**Idea** | **Idea** | ||
Line 18: | Line 18: | ||
Other channels? | Other channels? | ||
* Associated production with a Z(gamma?) via t/b loops would change the background to ttZ(gamma), which may have more manageable rates - but what would be our signal cross section in this case? | * Associated production with a Z(gamma?) via t/b loops would change the background to ttZ(gamma), which may have more manageable rates - but what would be our signal cross section in this case? | ||
- | * bb/tt associate production leading to 4 top or bbtt final states | + | * bb/tt associate production leading to 4 top or bbtt final states. Current limits from 8 TeV are of order 20 fb, close to the predicted production cross section for low A0 masses ~ 400 GeV. |
* Associated production with a single top (overtakes ttH around mH~ 300 GeV) | * Associated production with a single top (overtakes ttH around mH~ 300 GeV) | ||
+ | **Associated production** | ||
+ | |||
+ | This appears to be one of the more promising scenarios for 13 TeV. A projection study would be interesting. | ||
+ | The figure below is the LO cross section for A_0 production in association with ttbar at 13 TeV as a function of the mass for tan beta = 1. | ||
+ | |||
+ | {{:2015:groups:higgs:morehiggs:tta0.png?direct&200|}}{{:2015:groups:higgs:morehiggs:tja0.png?direct&200|}}{{:2015:groups:higgs:morehiggs:twa0.png?direct&200|}} | ||
+ | |||
+ | An summary of production cross sections for A0/H0 in the different production modes (ttH [Chris], bbH [Adam], tHj [Ken], tHW [Josemi], tbH+ [Aurelio, Aram]) might be an instructive thing to show. | ||
+ | |||
+ | Show as a function of mass for tan beta=1 in alignment for type I, II. | ||
+ | |||
+ | Material for runs: | ||
+ | {{:2015:groups:higgs:morehiggs:mg5_material.tar|}} | ||
**Literature** | **Literature** | ||
+ | |||
+ | [[http://arxiv.org/pdf/1405.7570v2.pdf]] | ||
+ | |||
+ | Djouadi et al. discuss A/H->tt in the context of hMSSM (simple and 'model independent' approach). Low tan beta and above the threshold A/H->tt becomes the dominant decay and production cross section is still significant. They stress that this study is needed to fully cover the M_A and tan beta parameter space. | ||
[[http://arxiv.org/abs/hep-ph/9404359]] | [[http://arxiv.org/abs/hep-ph/9404359]] | ||
Line 31: | Line 48: | ||
Maltoni et al. implementation of HZ production in Madgraph5_aMC@NLO. The ZH production cross section looks to be O(1) fb in their 2HDM benchmark scenarios with masses of 350, 440 and 500 GeV. This is to be compared with a recent calculation by Frixione et al. ([[http://arxiv.org/abs/1504.03446]]) of the background ttZ process quoting O(500) fb cross sections at LO with additional, non-negligible k-factors. | Maltoni et al. implementation of HZ production in Madgraph5_aMC@NLO. The ZH production cross section looks to be O(1) fb in their 2HDM benchmark scenarios with masses of 350, 440 and 500 GeV. This is to be compared with a recent calculation by Frixione et al. ([[http://arxiv.org/abs/1504.03446]]) of the background ttZ process quoting O(500) fb cross sections at LO with additional, non-negligible k-factors. | ||
+ | |||
+ | [[http://arxiv.org/abs/hep-ph/0106293]] | ||
+ | |||
+ | Out usual suspects return with predictions for associated production of a Higgs with a top. It is shown that this production mode overtakes ttH for masses around 300 GeV. | ||
[[http://arxiv.org/abs/1504.04630]] | [[http://arxiv.org/abs/1504.04630]] | ||
- | Recent study revisiting prospects at the LHC finding them not so promising when considering potential detector effects. In the pure ttbar case, they conclude that although with a lot of integrated luminosity, one may have the statistical power to see such a signal, the % level deviations in the tt invariant mass spectrum are likely to be outweighed by typical systematic uncertainties. The bb/tt associated production modes are also explored and are argued to merit further study at 13 TeV. Another potential channel of tH associated production is breifly mentioned (see next reference). | + | Recent study revisiting prospects at the LHC finding them not so promising when considering potential detector effects. In the pure ttbar case, they conclude that although with a lot of integrated luminosity, one may have the statistical power to see such a signal, the % level deviations in the tt invariant mass spectrum are likely to be outweighed by typical systematic uncertainties. The bb/tt associated production modes are also explored and are argued to merit further study at 13 TeV. Another potential channel of tH associated production is breifly mentioned (see previous reference). |
- | [[http://arxiv.org/abs/hep-ph/0106293]] | + | [[http://arxiv.org/abs/1504.07617]] |
- | Out usual suspects return with predictions for associated production of a Higgs with a top. It is shown that this production mode overtakes ttH for masses around 300 GeV. | + | Recent study on prospects for heavy Higgs boson searches in associated production, covering bbH/A, ttH/A, with H/A->tt, and H+tb, H->tb. It includes estimates for LHC 14 TeV and a 100 TeV pp collider. |
+ | |||
+ | [[http://arxiv.org/abs/1504.04605]] | ||
+ | |||
+ | ATLAS Run 1 search for 4-top production in the same-sign dilepton channel. | ||
+ | |||
+ | [[http://arxiv.org/abs/1505.04306]] | ||
+ | |||
+ | ATLAS Run 1 search for 4-top production in the single-lepton channel. |