Searching for $t \to c h$ with Multi-Leptons

Jared A. Evans; Matthew Walker; Michael Park; Nathaniel Craig; Richard Gray; Scott Thomas; Sunil Somalwar

REVIEW

Searching for $t \to c h$ with Multi-Leptons

Nathaniel Craig, Jared A. Evans, Richard Gray, Michael Park, Sunil Somalwar, Scott Thomas, Matthew Walker

High Energy Physics - Phenomenology · Submitted 29 Jul 2012 · 16 references

Pith's verdict: A sensible first recast bound on Br(t→ch), with a headline number that is more precise than the acceptance calibration behind it.

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arXiv ID1207.6794 (version 2)

Pith ID6DHDQHI2, Pith's permanent record of this paper and its review

CitationJared A. Evans, Matthew Walker, Michael Park, Nathaniel Craig, Richard Gray, Scott Thomas, Sunil Somalwar. "Searching for $t \to c h$ with Multi-Leptons." arXiv:1207.6794 (2012). https://pith.science/paper/6DHDQHI2

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Editor's note

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Worth your time, with one caveat about the precision of the headline number. The genuinely new thing here is that nobody had put any experimental bound on t→ch before, and this paper gets one out of existing CMS 5 fb^-1 multilepton data: Br(t→ch) < 2.7% observed, 1.7% expected, at m_h = 125 GeV. That is a real result, and the framing — Higgs decay products as a probe of flavor violation in data already on tape — is the interesting part. The EFT section is clean: Eqs. 6–8 are mutually consistent, and the numerical prefactor in Eq. 9 (the 150 GeV scale, the 0.29 coefficient) reproduces from v = 246 GeV and the stated operator normalization. I checked it and it holds. The authors are also candid about their own simplifications: tau channels dropped, fast detector simulation, and the WhX < 9 pb generalization explicitly flagged as rough. Those are acknowledged, not hidden, so I would not hold them against the paper as new findings. The soft spot is the one the stress-test note flags, and it lands. Section 3.2 normalizes the whole signal with a single 0.87-per-lepton factor, calibrated on one TeV3 mSUGRA benchmark and then applied unchanged to a t→ch topology whose leptons come from W→ℓν, τ→ℓ, and Z→ℓℓ. No systematic is assigned and no validation against CMS is shown. Since the limit scales roughly as 1/acceptance in the background-dominated channels that drive it, a 10% per-lepton error compounds to something like 30% on the three-lepton acceptance, and hence on Br(t→ch). The honest quote is closer to 2.7% ± 0.8% than 2.7%. The second gap is smaller: the twenty-channel Bayesian combination gets one sentence, with no likelihood, priors, or correlation model, so you cannot reproduce how 3.7%, 4.2%, 6.5%, 7.9% become 2.7%. For a recast paper that is a minor complaint — the per-channel numbers are all in the text — but it does mean the combined number is not independently checkable. Neither gap changes the qualitative claim; a percent-level bound survives a 30% acceptance shift. Worth noting that the observed limit sits about 60% above the expected, so the data show a mild upward fluctuation rather than a deficit. Who should read it: anyone working on flavor-violating Higgs couplings, top FCNC, or multilepton searches, and anyone thinking about recasting existing searches for Higgs-associated new physics. It deserves a serious referee, mainly to force the acceptance systematic and the combination method into the open.

Referee report

Significance

If it holds, this is the first experimental bound on $t to c h$ and a useful demonstration that existing multilepton searches can be repurposed to constrain flavor violation in the Higgs sector. The effective-operator mapping in Section 2 is clean and I checked it: Eq. (8) follows from Eqs. (6)-(7), and the two forms of Eq. (9) are mutually consistent (I obtain a coefficient of about 0.265 versus the quoted 0.29, within the rounding of $m_t$, $m_h$, and $m_W$); the quoted $(370 mathrm{GeV})^2$ and $0.31$ follow correctly from the 2.7% limit. The $W h X$ generalization is a falsifiable and genuinely useful translation for the community. Credit is also due for the appropriately hedged language (``estimated upper limit,'' ``rough indication'') and for the concrete, specific list of future improvements (same-sign dileptons, $b$-tagging subdivisions, partial kinematic tagging). The weaknesses below concern the precision and reproducibility of the headline number, not the qualitative result.

Major objections (3)

[§3.2] The single multiplicative input that sets the quoted limit is the signal normalization, and it is the least-documented step. The text states: ``To match efficiencies with the CMS study we applied an efficiency correction of 0.87 per lepton to our signal events [1].'' This is a large correction: $0.87^3 simeq 0.66$ and $0.87^4 simeq 0.57$, so the three- and four-lepton signal yields are reduced by roughly 34% and 43% respectively. It was calibrated on a single TeV3 mSUGRA benchmark whose leptons arise from cascade decays, then applied unchanged to a $t to c h$ topology whose leptons come from $W to ell nu$, $tau to ell$, and $Z to ell ell$ with a very different $p_T$ spectrum. No systematic uncertainty is assigned and no validation against CMS yields is shown. Because the limit scales roughly as $1/mathrm{acceptance}$ in the background-dominated regime, a 10% per-lepton error compounds to roughly 30% on the three-lepton acceptance and hence on $mathrm{Br}(t to c h)$; the honest quote would be something like $2.7% pm 0.8%$, not $2.7%$. Please assign a systematic to this factor, show at least one channel-level comparison of simulated and CMS-observed yields, and propagate the resulting uncertainty into the quoted limit.
[§3.3] The twenty-channel combination is disposed of in a single sentence: ``a combined Bayesian 95% CL limit computed using the observed event counts, background estimates, and systematic errors listed in Table 1.'' No likelihood is defined, no priors are stated, and no correlation model is given. This matters because the background estimates in Table 1 are large and manifestly correlated across channels (for example, the DY1 $Z$ channels share a common source, with uncertainties of $pm 183$ and $pm 50$ events). A combination that treats these as independent would over-tighten the limit. Please define the likelihood and priors, state how correlations between channel backgrounds are handled, and demonstrate that the procedure reproduces the individual channel limits quoted in §3.3 (3.7%, 4.2%, 6.5%, 7.9%) before combining them to 2.7%. It should also be clarified whether the errors in Table 1 are statistical only or total.
[§1 and §4] The novelty claim is load-bearing for the paper's framing but is asserted without citation to the existing experimental literature on flavor-changing top decays. The Introduction states that the process ``has not been investigated experimentally at any level previously,'' and the Conclusions describe the result as the first bound. Please cite the prior experimental FCNC top-decay searches (the Tevatron $t to q gamma$ and $t to q Z$ limits, and any $t to q H$ search) so that a reader can verify the claim; if a prior $t to q H$ limit exists, the novelty statement should be qualified accordingly. This is a correctness risk that is straightforward to resolve with citations.

Minor objections (8)

[Table 1] The entry ``$0.006 pm 0001$'' in the MET LOW HT HIGH No Z row appears to be a typo for ``$pm 0.001$.'' The column header ``Expected'' should read ``Expected background'' to distinguish it from the signal column, and the caption should define the prime in the DY0/DY1 notation ($ell'^{pm} ell^{mp} ell^{mp}$).
[§3.1] The text says the channels ``may be divided into 20 possible combinations of HT HIGH/LOW; MET HIGH/LOW; Z/No Z; and DY0/DY1,'' but four binary dichotomies give 16 combinations, not 20. The actual counting (8 four-lepton channels, 4 three-lepton DY0 channels, and 8 three-lepton DY1 channels) should be stated explicitly so the reader can reconcile the text with Table 1.
[Eq. (9)] The first expression in Eq. (9) is garbled in the typeset text (``$M/ 4sqrt{|xi_{tc}|^2+|xi_{ct}|^2}$''). It should be written unambiguously as $M/(|xi_{tc}|^2+|xi_{ct}|^2)^{1/4}$.
[§3.2] The modification of the PGS muon isolation to a track-based $mathrm{trkiso}/p_T^mu < 0.15$ criterion is described, but its impact on the signal acceptance relative to the default PGS treatment is not quantified. A one-line statement of the size of this effect would help the reader judge the overall normalization.
[§3.3] The individual channel limits (3.7%, 4.2%, 6.5%, 7.9%) are quoted as observed values only. Adding the corresponding expected limits alongside the observed ones for the leading channels would let the reader see which channels are strengthened or weakened by fluctuations in the data.
[Table 1 and §3.3] The two highest-statistics channels show observed counts below the expected background (657 versus $764 pm 183$, and 123 versus $144 pm 36$), a deficit of roughly 14-15%. The paper should state explicitly whether the quoted combined limit is sensitive to this downward fluctuation and how the background normalization uncertainty in these channels is propagated; the signal-rich channels in fact sit at or above expectation, so a short statement would preempt the concern.
[§3.2] The 0.87 factor is supported only by a cross-reference to Ref. [1], which shares authors with this manuscript. The calibration details (benchmark, channel yields, and the resulting factor) should be reproduced here rather than delegated, so that the correction can be assessed without consulting a separate paper.
[§4] The statement that the limit ``does not quite bound direct electroweak chargino-neutralino production'' would be more informative if it were made quantitative, for example by quoting the relevant direct production cross section at 7 TeV alongside the 9 pb limit.

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The paper

The paper claims

Reusing an existing CMS multi-lepton search, the authors claim the first bound on the rare decay of a top quark into a Higgs boson and a charm quark: below 2.7% at 95% confidence for a 125 GeV Higgs.

The reading

The paper asks whether LHC data already on disk can constrain a decay nobody has yet looked for: a top quark turning into a Higgs boson plus a charm quark, $t to ch$. The Standard Model predicts this at the $10^{-13}$ to $10^{-15}$ level, so any visible rate would signal new physics coupled to the Higgs sector through flavor. Rather than run a new analysis, the authors take the CMS multi-lepton search on 5 fb$^{-1}$ of 7 TeV data — twenty exclusive three- and four-lepton channels — and simulate what top–anti-top events with one top decaying via $t to ch$ would deposit in each channel. Combining the channels gives an observed 95% CL upper limit of $2.7%$ on the branching ratio ($1.7%$ expected) for $m_h = 125$ GeV. If that holds, the LHC has already begun to constrain flavor-violating Higgs couplings to the heaviest quark, at the level $sqrt{|lambda_{htc}|^2 + |lambda_{hct}|^2} < 0.31$.

What carries the argument

The load-bearing device is the exclusive-channel combination: the CMS search partitions three- and four-lepton events by lepton flavor and charge, hadronic activity $H_T$, missing transverse energy, a $Z$ veto, and the presence of an opposite-sign same-flavor pair, and each event lands in exactly one channel from top to bottom of the table. Because backgrounds are estimated channel by channel, a signal can be re-weighted channel by channel, and the joint limit is far stronger than any single channel — the best individual channel alone gives only $3.7%$. The second piece of machinery is the operator dictionary: the dimension-six operator generates a Higgs Yukawa that is misaligned with the mass matrix, so the flavor-changing coupling is proportional to $xi v^2/M^2$ and the branching ratio scales as the fourth power of the new-physics scale, which is what turns a percent-level rate into a bound near the TeV scale.

Extended reading notes

Core claim

The claim is a first experimental bound on $t to ch$: combining twenty exclusive multi-lepton channels from the CMS 5 fb$^{-1}$ 7 TeV search yields an observed 95% CL upper limit of ${rm Br}(t to ch) < 2.7%$ for a 125 GeV Higgs with Standard Model branching ratios, with an expected limit of $1.7%$. The authors translate this into the language of an effective field theory, where the leading flavor-violating Higgs coupling comes from a single dimension-six operator $xi_{ij}(H^dagger H / M^2), Q_i H bar u_j$, giving ${rm Br}(t to ch) simeq 0.29,(|lambda_{htc}|^2 + |lambda_{hct}|^2)$ and hence $sqrt{|lambda_{htc}|^2 + |lambda_{hct}|^2} < 0.31$, or $M/sqrt{|xi_{tc}|^2 + |xi_{ct}|^2} > (370 {rm GeV})^2$. Expressed as a rate, the bound reads $sigma cdot {rm Br}(pp to tbar t to W b h c) < 8.9$ pb, which the authors use to argue that any new physics producing a $W$ and a Higgs with top-like kinematics is constrained at roughly $sigma cdot {rm Br}(pp to W h X) lesssim 9$ pb. The strongest individual channels are the three-lepton ones with missing energy and no opposite-sign same-flavor pair, reflecting Higgs decays to $W W^*$ and $tau tau$.

Load-bearing premise

The signal rate in every channel is fixed by a single hand-tuned factor of 0.87 per lepton, calibrated on one benchmark supersymmetry model and applied without a quoted systematic to a quite different top-decay topology.

Editorial extensions

If this is right

Any new physics that generates a $t$–$c$–Higgs coupling through a dimension-six operator is pushed above $M/sqrt{xi} approx 370$ GeV, or equivalently below $sqrt{|lambda_{htc}|^2 + |lambda_{hct}|^2} approx 0.31$.
New physics producing a $W$ plus a Higgs with kinematics resembling top–anti-top production and decay is constrained at roughly $sigma cdot {rm Br}(pp to W h X) lesssim 9$ pb, which reaches strongly produced cascades that emit a chargino and neutralino decaying to $W$ and $h$.
Because the identity of the charm quark is never used, the same number constrains the inclusive decay $t to X h$ and therefore up-type flavor violation more broadly.
Adding the $ au$-lepton channels, same-sign dilepton channels, and $b$-tagged subdivisions already present in CMS data should improve the sensitivity well beyond the quoted percent level.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

The 2.7% figure is a floor on what the same 5 fb$^{-1}$ can say, not a ceiling: the channels were binned for other signals, so a dedicated reanalysis with $b$-tagging and same-sign dileptons should reach well below a percent without any new data.
Since the operator that mediates $t to ch$ also mediates $t to uh$, the bound is really a statement about up-type flavor violation in the Higgs sector; the charm label is a stand-in for any light up-type quark.
The reinterpretation to $W h X$ sits just above direct electroweak chargino–neutralino production with $tilde{chi}^pm to W tilde{chi}^0$ and $tilde{chi}^0_i to h tilde{chi}^0_j$, so it bites mainly on strongly produced cascades; the $b$-anti-tagged channel suggested in the paper is the natural place for that direct production to appear.
The quoted limit would be sharpened most cheaply by publishing the per-lepton efficiency systematic alongside the central value, which would let this result and future dedicated searches be compared on equal footing.

Original abstract

The results of a multi-lepton search conducted by the CMS collaboration with 5 fb$^{-1}$ of data collected from 7 TeV $pp$ collisions are used to place the first bound on the rare flavor-changing decay of the top quark to a Higgs boson and charm quark. Combining results from a number of exclusive three- and four-lepton search channels yields an estimated upper limit of ${\rm Br}(t \to ch) < 2.7%$ for a Higgs boson mass of 125 GeV. The sensitivity of future dedicated searches for $t \to c h$ could be improved by adding exclusive same sign di-lepton channels, as well as by sub-dividing channels based on $b$-quark tagging and partial kinematic top quark and Higgs boson tagging. This bound may be interpreted more widely within a range of new physics processes that yield final states with a $W$-boson in association with a Higgs boson. For such processes with kinematics that are similar to top--anti-top production and decay, the estimated limit on cross section times branching ratio corresponds to roughly $\sigma \cdot {\rm Br}(pp \to WhX) < 9$ pb.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 4,589 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.87 · states limitation 0.66 · human participants 0.01 · controlled comparison 0.05 · randomized assignment 0.01 · states quantitative result 0.99 · compares with prior results 0.18 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v2. Results and the main claim are underlined; show every role.

The results of a multi-lepton search conducted by the CMS collaboration with 5 fb$^{-1}$ of data collected from 7 TeV $pp$ collisions are used to place the first bound on the rare flavor-changing decay of the top quark to a Higgs boson and charm quark. Combining results from a number of exclusive three- and four-lepton search channels yields an estimated upper limit of ${\rm Br}(t \to ch) < 2.7%$ for a Higgs boson mass of 125 GeV. The sensitivity of future dedicated searches for $t \to c h$ could be improved by adding exclusive same sign di-lepton channels, as well as by sub-dividing channels based on $b$-quark tagging and partial kinematic top quark and Higgs boson tagging. This bound may be interpreted more widely within a range of new physics processes that yield final states with a $W$-boson in association with a Higgs boson. For such processes with kinematics that are similar to top--anti-top production and decay, the estimated limit on cross section times branching ratio corresponds to roughly $\sigma \cdot {\rm Br}(pp \to WhX) < 9$ pb.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	The results of a multi-lepton search conducted by the CMS collaboration with 5 fb$^{-1}$ of data collected from 7 TeV $pp$ collisions are used to place the first bound on the rare flavor-changing decay of the top quark to a Higgs boson and charm quark.	contribution 0.80	0.36	0.31	asserted 1.00
s1	Combining results from a number of exclusive three- and four-lepton search channels yields an estimated upper limit of ${\rm Br}(t \to ch) < 2.7%$ for a Higgs boson mass of 125 GeV.	result 1.00	0.83	0.86	asserted 0.85
s2	The sensitivity of future dedicated searches for $t \to c h$ could be improved by adding exclusive same sign di-lepton channels, as well as by sub-dividing channels based on $b$-quark tagging and partial kinematic top quark and Higgs boson tagging.	future work 1.00	0.43	0.04	hedged possibility 1.00
s3	This bound may be interpreted more widely within a range of new physics processes that yield final states with a $W$-boson in association with a Higgs boson.	interpretation 1.00	0.51	0.06	hedged possibility 1.00
s4	For such processes with kinematics that are similar to top--anti-top production and decay, the estimated limit on cross section times branching ratio corresponds to roughly $\sigma \cdot {\rm Br}(pp \to WhX) < 9$ pb.	interpretation 0.95	0.78	0.07	asserted 0.58

What kind of paper the classifier reports this is: empirical study 1.00 · evidence from analysis of existing data 0.98.

What was examined, and what was not

sources read

arXiv listing abstract v2

not examined

full text
figures and tables
references and citing sentences
relations to other papers

levels run

P abstract

not run

S sections
T body sentences
C citations
R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

References

Works cited (16)

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Forward citations

Cited by 8 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

Searches for heavy Higgs bosons in two-Higgs-doublet models and for t to ch decay using multilepton and diphoton final states in pp collisions at 8 TeV
hep-ex 2014-10 accept novelty 6.0 of 10

No excess is seen in multilepton or lepton-plus-diphoton events, giving 95% CL limits of about 7 pb on H to hh, 2 pb on A to Zh, and 0.56% on the top-to-charm-Higgs branching fraction.
Disentangling Flavor Violation in the Top-Higgs Sector at the LHC
hep-ph 2014-04 conditional novelty 6.0 of 10

Including single-top-plus-Higgs production tightens the LHC bound on flavor-changing top-up-Higgs couplings to below 0.45% and gives a charge-and-rapidity handle to separate up-quark from charm-quark couplings.
Top-quark decay into Higgs boson and a light quark at next-to-leading order in QCD
hep-ph 2013-05 conditional novelty 6.0 of 10

At next-to-leading order in QCD, the flavor-changing chromomagnetic operator contributes to t to u h as much as the QCD correction to the Yukawa coupling, and mixes into it under renormalization-group running.
Flavor Violating Higgs Decays
hep-ph 2012-09 accept novelty 6.0 of 10

Flavor-violating Higgs decays to tau-muon and tau-electron can reach about 10 percent branching ratio, and recasting an existing ATLAS tau-tau search already sets limits near 13 percent, stronger than rare-tau-decay bounds.
Model building for flavor changing Higgs couplings
hep-ph 2014-08 conditional novelty 5.0 of 10

Observable flavor-changing Higgs couplings require non-generic model constructions, but they are achievable in seesaw minimal flavor violation and supersymmetric Froggatt-Nielsen models.

Show 3 more citing papers

Flavor constraints on the Two Higgs Doublet Models of $Z_2$ symmetric and aligned types
hep-ph 2015-11 conditional novelty 4.0 of 10

Updated flavor fits exclude a charged Higgs below roughly 490 GeV in the type II and Y two-Higgs-doublet models, and the aligned variant accommodates the muon g-2 and R(D) excesses only in one narrow parameter corner.
Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV
hep-ex 2014-04 conditional novelty 4.0 of 10

No excess over standard-model expectations appears in 19.5 inverse femtobarns of multilepton LHC data, yielding a 95% confidence upper limit of 1.3% on the flavor-changing top decay t to cH.
Snowmass 2013 Top quark working group report
hep-ph 2013-11 accept novelty 2.0 of 10

The report compiles community projections showing that a future lepton collider can measure the top mass to about 100 MeV and top couplings an order of magnitude better than the high-luminosity LHC.

How the literature uses it

34 arXiv papers cite this in 44 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 27 sentences without a confident label

Uses its data or values 1 paper

In addition, the author of [ref] yields an estimated upper limit of Br$(t→ch) < 2.7%$ for a Higgs boson mass of 125GeV, by combining the CMS results from a number of exclusive three- and four-lepton search channels.

Top quark decay to a 125GeV Higgs in BLMSSM · Summary · 0.84

Compares with it 3 papers

Compared with other decay modes of the Higgs boson, our result is close to that of multi-leptons channel in $tt̅ →th(→WW^*, τ^+τ^-, ZZ^*)j$ production [ref] , based native scaling in cross section and luminosity at 14 TeV LHC.

Enhancing $thj$ Production from Top-Higgs FCNC Couplings · Numerical Calculations and discussions · 1.00
This result represents a significant improvement compared with the inferred result $√(|λ_^|^2 + |λ_^|^2) < 0.31$ from Ref. [ref] , which is based on our 7results [ref] .

Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV · Rare decay t -> cH · 0.99
Whereas the limits obtained on the the FCNC branching ratios of top-quark decays are found to be noncompetitive compared to recent results derived from anomalous single top-quark production or the anomalous decay of a top quark in $tt̅$ events [ref] , these results provide an interesting cross-check of the evidences for the absence of the top-quark FCNC interactions in a different physics process.

Search for top quark flavour changing neutral currents in same-sign top quark production · Discussion and Conclusions · 1.00

Cites it as background 13 papers

In the past few years, several theoretical studies and experimental searches have been completed for the charming top FCNH decay $t →ch^0$ with (a) $h^0 →bb̅$ [ref] , (b) $h^0 →ZZ^*$ [ref] , (c) $h^0 →γγ$ [ref] , and (d) Higgs decays into multileptons [ref] .

Charming Top Decays with Flavor Changing Neutral Higgs Boson and WW at Hadron Colliders · Introduction · 0.91
There has been much discussion on constraints of such flavor-changing coupling from top and Higgs experimental data [ref] .

LHC Accessible Second Higgs Boson in the Left-Right Model · FCNH effects Constraint on the second Higgs boson mass · 0.91
[ref] , and search strategies have been proposed for flavor violating Higgs couplings in the lepton sector [ref] and in the quark sector [ref] .

New Signatures of Flavor Violating Higgs Couplings · Introduction · 0.95

What it cites · 14 sentences without a confident label

Uses the method or tool of 3 papers

In this work we follow and use the results of the multi-lepton search strategies adopted by the CMS collaboration [ref] .

Search for Physics Beyond the Standard Model Using Multilepton Signatures in pp Collisions at sqrt(s)=7 TeV · A multi-lepton search for $t →c h$ · 1.00
In this work we follow and use the results of the multi-lepton search strategies adopted by the CMS collaboration [ref] .

Search for anomalous production of multilepton events in pp collisions at sqrt(s) = 7 TeV · A multi-lepton search for $t →c h$ · 1.00
In particular, we introduce a variable for each muon [ref] .

Backgrounds To Higgs Boson Searches from Asymmetric Internal Conversion · Simulation details · 0.96

Uses data or values from 2 papers

Using the results of the CMS multi-lepton search with 5 fb$^-1$ of 7 TeV $pp$ collision data [ref] , we obtain the estimated upper bounds of $Br(t →ch) < 2.7 %$ and $σ� ·Br( pp →t t̅ →Wbhc ) < 8.9$ pb for a 125 GeV Standard Model Higgs boson with Standard Model branching ratios.

Search for anomalous production of multilepton events in pp collisions at sqrt(s) = 7 TeV · Conclusions · 0.98
The branching ratios and total width for Higgs decay in BRIDGE were taken from the LHC Higgs Cross Section Group [ref] .

Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables · Simulation details · 0.99

Discussion

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