Pair production of scalar leptoquarks at the LHC

M. Kr\"amer; M. Spira; P.M. Zerwas; T. Plehn

REVIEW

Pair production of scalar leptoquarks at the LHC

M. Krämer, T. Plehn, M. Spira, P.M. Zerwas

High Energy Physics - Phenomenology · Submitted 2 Nov 2004 · 23 references

Pith's verdict: A short, competent NLO sequel whose Table I is the actual product; the physics is standard and the cross-check is real, but the quoted precision is softer than the text implies.

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arXiv IDhep-ph/0411038 (version 2)

Pith ID6BKG5CGV, Pith's permanent record of this paper and its review

CitationM. Kr\"amer, M. Spira, P.M. Zerwas, T. Plehn. "Pair production of scalar leptoquarks at the LHC." arXiv:hep-ph/0411038 (2004). https://pith.science/paper/6BKG5CGV

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Editor's note

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This is the paper you cite when you need a number for scalar leptoquark pair production at the LHC, and that is basically what it is: a Brief Report that takes the authors' own Tevatron NLO machinery and re-evaluates it at 14 TeV. The deliverable is Table I — cross sections and K-factors from 200 to 2000 GeV, with a CTEQ6/MRST2002 comparison. Nothing here is a new method, and the paper says so in the abstract (abstract:s3). What it does, it does cleanly: the Born terms in Eq. (2) are consistent with the threshold expansions in Eq. (5), the asymptotic 9:2 ratio in Eq. (6) checks out, and the agreement with squark-pair production in the large-gluino limit (after dropping the sub-0.5% four-squark terms) is a genuine independent validation, not a decorative one. The authors also flag the one comparison that would have been circular — Ref. [20] reuses their code — and discount it. That is honest bookkeeping and I'd like to see more of it. The pointlike-limit assumption behind the parameter-free claim is stated explicitly, not smuggled in, and for a renormalizable color-triplet scalar it is the right leading term. Scope limitation, not an error. Two soft spots, both minor. First, truncation reliability is argued by analogy in footnote 2: Higgs gluon fusion has K ~ 1.5-2 and moves ~20% at NNLO, so leptoquarks should behave similarly. But gg -> LQ LQ is tree-level scalar QCD with different color structure than the top-loop Higgs coupling; the analogy is suggestive, not a demonstration. Second, Fig. 2 shows the NLO scale dependence flattening around mu ~ M_LQ/4, while Table I is quoted at mu = M_LQ, on the shoulder. The residual band at M_LQ appears only graphically in Fig. 3 and is never given as a number. Neither point threatens the qualitative claim — NLO is above LO and the scale dependence is much reduced — but the quoted precision is a bit softer than the prose suggests. Who should read it: anyone setting leptoquark limits at the LHC, and anyone wanting a clean worked example of NLO scalar-pair production. It deserves a referee, though a light one; the calculation is standard and the checks are in place.

Referee report

Significance

If correct, Table I supplies the reference production numbers that LHC leptoquark searches should use, and the K-factors of 1.5-2.1 are large enough to matter for the quoted experimental reach of 1.3-1.5 TeV. The calculation is parameter-free in the pointlike limit, which the manuscript states explicitly, and the paper provides a genuine independent structural check: agreement with squark-antisquark production in the large-gluino limit once the sub-0.5% four-squark self-coupling contributions are removed. The scale-dependence study in Fig. 2 and the parton-density comparison in Table I are the right diagnostics for a hadron-collider NLO prediction, and the paper is candid about the unphysical negative sigma_gq induced by mass factorization. This is a useful, self-contained reference for the experimental community rather than a new formal result.

Major objections (2)

[Conclusions paragraph ('the NLO corrections shift the LQ mass limit upward by an amount of about 100 GeV')] The ~100 GeV upward shift of the LHC mass reach is asserted in the concluding paragraph but is not derived anywhere in the manuscript. No reference cross section at the experimental reach, no integrated luminosity, and no selection efficiency are given, so the number cannot be reproduced or checked from the paper alone; the reach of 1.3-1.5 TeV is quoted from Refs. [9,10] but the mapping from a K-factor of order 1.9 onto a 100 GeV mass shift is not shown. Please either add the short derivation (the cross section at the reach and the assumed luminosity/efficiency, with BR = 1 stated explicitly as it is for the Tevatron limits in the introduction) or soften the statement to a qualitative remark that the reach is extended, with the size left to the experimental analyses.
[Fig. 2, Fig. 3 and Table I (scale dependence)] The claim that the NLO prediction is stabilized is demonstrated at the broad maximum near mu ~ M_LQ/4, whereas the reference numbers in Table I are quoted at mu = M_LQ, which sits on the shoulder of that maximum; the residual scale band at the quoted scale appears only graphically in Fig. 3 and is never given numerically. Since the abstract's second sentence and the 'conservative lower limit' conclusion both rest on this stability, please add the NLO scale-uncertainty band at mu = M_LQ (or over the stated interval [M_LQ/2, 2 M_LQ]) as a column or a parenthetical entry in Table I, so that the reader can see how much of the K-factor is genuinely under control. Relatedly, footnote 2 supports truncation reliability by analogy with Higgs gluon fusion, but gg -> LQ LQ is tree-level scalar QCD with a different color structure from the top-loop-induced Higgs coupling, so 'isomorphic' overstates the correspondence; the explicit scale variation is the stronger and more direct argument and should carry the weight.

Minor objections (7)

[Eq. (4)] As typeset, the prefactor of Eq. (4) reads alpha_s^2(M_LQ^2) M_LQ^2 times the scaling functions, which is dimensionally inconsistent with a partonic cross section. Comparing with Eq. (2) near threshold (using s-hat = 4 M_LQ^2) shows that the mass factor should appear in the denominator, i.e. alpha_s^2(M_LQ^2)/M_LQ^2, so that f^B_gg = 7 pi beta/384 and f^B_qqbar = pi beta^3/54 reproduce the beta -> 0 limits of Eq. (2). Please correct or clarify the typesetting.
[Eq. (5)] The threshold expressions for f^{V+S}/f^B and f^H/f^B in Eq. (5) are difficult to parse as printed (for example the entries rendered as '11336 beta' and '-148 beta'). Please check the fractions and, if space permits, present them in a small table so that the threshold behaviour quoted in the text can be verified against the formulae.
[Introduction, first paragraph] The sentence 'If the Yukawa couplings for scalar leptoquark couplings to quarks and leptons of the first and second generation ... is kept at small values' has a grammatical mismatch ('couplings ... is') and a redundant 'couplings ... couplings'. Please rephrase.
[Text following Eq. (2)] The statement that quark-antiquark annihilation provides '30% of the production cross section for leptoquark masses of about 1.5 TeV' is slightly above what Table I shows: the qqbar fraction is 0.26 at 1.4 TeV and 0.28 at 1.6 TeV, i.e. about 27% at 1.5 TeV. Please align the text with the table.
[Table I caption] The caption should state explicitly that the 'gg : qqbar : gq' entries are fractions of the total NLO cross section (they sum to unity in each row), so that the negative gq entry is not misread as a fraction of a physical subprocess cross section.
[Text preceding the acknowledgments (comparison with Ref. [20])] The remark that agreement with Ref. [20] 'is only of limited value as the K-factors presented in Ref. [20] have been obtained by using the NLO code of the calculation Ref. [11]' is somewhat opaque to a reader who does not know the history. Please state in one clause what the present calculation adds relative to Ref. [20] (new energy, updated parton densities, scale band) so the comparison reads as a clarification rather than a priority remark.
[Fig. 3] The figure would be more informative if the curve at the maximum-stability scale mu ~ M_LQ/4 were shown alongside the mu = M_LQ curve and the shaded band, since the text singles out that scale as the most stable choice.

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The paper

The paper claims

The paper argues that next-to-leading-order QCD corrections make scalar leptoquark pair production at the 14 TeV LHC a parameter-free prediction and raise the mass reach by about 100 GeV.

The reading

The paper sets out to give the LHC a reliable production-rate prediction for pairs of scalar leptoquarks, the hypothetical color-triplet particles that couple quarks to leptons. Its starting point is that for the first two generations the gluon couplings of a scalar leptoquark are fixed by the same SU(3) color gauge symmetry that governs scalar QCD, so pair production has no free coupling constant once the leptoquark mass is chosen. The authors extend an earlier Tevatron calculation to 14 TeV proton-proton collisions and add next-to-leading-order QCD corrections from virtual gluons, gluon bremsstrahlung, and initial-state parton splitting. They find that these corrections reduce the renormalization/factorization scale dependence, raise the cross section by factors of about 1.5 to 2.1 over the mass range 200-2000 GeV, and shift the LHC mass reach upward by roughly 100 GeV.

What carries the argument

The mechanism is the pointlike scalar-QCD coupling of a color-triplet leptoquark, which makes the $gg �� LQ��overline{LQ}$ and $q��bar q �� LQ��overline{LQ}$ rates depend only on the leptoquark mass. The authors compute the NLO corrections from virtual gluon exchange, soft and hard gluon emission, and initial-state collinear factorization in the $��overline{��mathrm{MS}}$ scheme, using CTEQ6L1 and CTEQ6M parton densities. Near threshold they track the Coulomb rescattering factors that remove the leading $��$ suppression in the singlet and octet channels, and they use the asymptotic NLO scaling functions for the high-energy region. The resulting K-factors and channel decomposition are what convert the Born formula into the numbers an experiment can use.

Extended reading notes

Core claim

The central claim is that the next-to-leading-order QCD calculation turns scalar leptoquark pair production at the LHC into a controlled, parameter-free prediction. For a color-triplet scalar with only minimal gauge couplings, the Born cross sections are fixed by Eq. (2), and the NLO corrections are large but stabilize the scale dependence; at the standard scale $��=M_{LQ}$ the K-factor runs from about 1.48 at 200 GeV to about 2.07 at 2 TeV. The paper presents the resulting cross sections and channel fractions in Table I and argues that Born calculations at the same scale give a conservative lower limit, while the NLO result moves the upper mass reach of the LHC by about 100 GeV. The calculation is explicitly restricted to scalar leptoquarks; vector leptoquarks are excluded because their effective theory is not renormalizable.

Load-bearing premise

The load-bearing premise is that the leptoquark is a pointlike color-triplet scalar whose gluon couplings are fixed entirely by SU(3) gauge symmetry, with no anomalous chromomagnetic moment, compositeness form factor, or other non-minimal coupling.

Editorial extensions

If this is right

The cross sections in Table I become the reference NLO numbers for ATLAS and CMS searches, rather than Born-level estimates.
Because the NLO rate is larger, a leptoquark of a given mass is easier to discover, and the quoted LHC reach extends by about 100 GeV.
A null search should set limits using the NLO prediction; using the Born rate at the same scale would be conservative and would underestimate the reach.
The residual scale band between $��=M_{LQ}/2$ and $2M_{LQ}$, together with PDF variations below 10% up to 1.5 TeV, defines the theory uncertainty an experimental limit should carry.
Gluon fusion dominates at low mass, while quark-antiquark annihilation grows to about 30% of the rate at the high-mass end.

Reading between the lines

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

If a leptoquark is discovered, a measured pair-production rate that matches Table I would directly fix its mass under the minimal scalar hypothesis, while a mismatch would point to non-minimal chromomagnetic couplings or compositeness.
The size of the K-factor suggests that an NNLO calculation could still move the central rate, as it does for Higgs production; the quoted reach shift should therefore be read as an NLO result awaiting a higher-order check.
Because the prediction is parameter-free, an early LHC non-observation can be converted into a mass bound without scanning over leptoquark coupling strengths, provided the scalar and minimal-coupling assumptions hold.

Original abstract

Theoretical predictions for the production cross sections of leptoquarks at the CERN LHC are presented including higher-order QCD corrections. These corrections reduce the dependence on the renormalization/factorization scales significantly. Moreover, they are required to exploit the leptoquark mass reach of the LHC experiments. In this sequel to an earlier analysis performed for the Tevatron collider we extend the leptoquark analysis to the LHC energy.

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, 3,516 input tokens, $0.0001 reported.

What the abstract itself states, as probabilities: claims first 0.04 · states limitation 0.14 · human participants 0.01 · controlled comparison 0.06 · randomized assignment 0.01 · states quantitative result 0.07 · compares with prior results 0.51 · 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.

Theoretical predictions for the production cross sections of leptoquarks at the CERN LHC are presented including higher-order QCD corrections. These corrections reduce the dependence on the renormalization/factorization scales significantly. Moreover, they are required to exploit the leptoquark mass reach of the LHC experiments. In this sequel to an earlier analysis performed for the Tevatron collider we extend the leptoquark analysis to the LHC energy.

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	Theoretical predictions for the production cross sections of leptoquarks at the CERN LHC are presented including higher-order QCD corrections.	contribution 1.00	0.86	0.14	asserted 0.99
s1	These corrections reduce the dependence on the renormalization/factorization scales significantly.	result 0.87	0.76	0.15	asserted 1.00
s2	Moreover, they are required to exploit the leptoquark mass reach of the LHC experiments.	interpretation 0.77	0.37	0.18	asserted 1.00
s3	In this sequel to an earlier analysis performed for the Tevatron collider we extend the leptoquark analysis to the LHC energy.	contribution 0.56	0.78	0.04	asserted 0.98

What kind of paper the classifier reports this is: theoretical result 0.99 · evidence from simulation or computation 0.76.

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

Figures

**Figure 1.** FIG. 1: Generic set of leading-order Feynman diagrams for le

**Figure 2.** FIG. 2: Variation of the LO and NLO cross sections for

**Figure 3.** FIG. 3: Total cross section for

Figures reproduced from arXiv:hep-ph/0411038 by the authors.

References

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hep-ex 2015-09 conditional novelty 5.0 of 10

No leptoquark signal appears in 8 TeV CMS data, excluding first-generation scalar leptoquarks below 1010 GeV and second-generation below 1080 GeV at 95% CL for unit branching fraction to a charged lepton.
Single Productions of Colored Particles at the LHC: An Example with Scalar Leptoquarks
hep-ph 2015-03 conditional novelty 5.0 of 10

Including single leptoquark production in CMS's 8 TeV pair-production search raises the mass exclusion limit by roughly 6 to 20 percent and yields coupling bounds competitive with HERA.
Search for pair production of third-generation scalar leptoquarks and top squarks in proton-proton collisions at sqrt(s) = 8 TeV
hep-ex 2014-08 accept novelty 5.0 of 10

No excess is observed in tau-plus-bottom final states, excluding third-generation scalar leptoquarks below 740 GeV and chargino-mediated R-parity-violating top squarks below 580 GeV at 95% confidence level.
Composite Leptoquarks at the LHC
hep-ph 2009-10 conditional novelty 5.0 of 10

Composite leptoquarks coupled mainly to third-generation fermions are a plausible consequence of partial compositeness, and the same mixing that suppresses flavour-changing processes may let them evade existing rare-d...
Search for heavy neutrinos and third-generation leptoquarks in hadronic states of two $\tau$ leptons and two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV
hep-ex 2018-11 conditional novelty 4.0 of 10

In 35.9 fb^-1 of 13 TeV CMS data with two hadronic taus and two jets, no excess appears, excluding right-handed W bosons below 3.50 TeV and scalar leptoquarks below 1.02 TeV at 95% confidence level.
Searches for scalar leptoquarks in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
hep-ex 2015-08 accept novelty 4.0 of 10

No leptoquark signal appears in 20 fb^-1 of 8 TeV ATLAS data, so scalar leptoquarks are excluded below 1050 GeV (first generation), 1000 GeV (second generation), and roughly 625 to 640 GeV (third generation).
Pair Production of Scalar Leptoquarks at the LHC to NLO Parton Shower Accuracy
hep-ph 2015-06 conditional novelty 4.0 of 10

Scalar leptoquark pair production at the LHC is simulated at NLO QCD matched to a parton shower, with cross sections, K-factors and kinematic distributions released as a public code.
Low Scale Quark-Lepton Unification
hep-ph 2013-07 conditional novelty 4.0 of 10

A SU(4)_C x SU(2)_L x U(1)_R model unifies quarks and leptons at a scale near 1000 TeV and predicts TeV-scale scalar leptoquarks, with neutrino masses from an inverse seesaw.

How later papers used it

80 later papers cite it

Evidence: substantial. 78 of the citing papers share no author with it, and 27 of those carry a confident label from Pith's citation classifier.

Pith read 18 of the 109 citing sentences, choosing only those whose citation markers point at this paper alone, and wrote the paraphrases from them. The summary, the counts, the evidence level, the links and the quotes come from code; the summary counts the papers listed below. A later paper is listed under a label when Pith's citation classifier gives one of its sentences that label at probability 0.8 or more (0.95 for support), Pith's reading finds that the citing paper itself did it, and a second check confirms the paraphrase against the sentence. This section lists uses only. It does not list criticism or disagreement, so their absence here says nothing about how the paper has been received. Papers that share an author with this one are listed apart, under "By the same authors". A quote is the citing authors' own sentence, shown when their paper's licence is CC BY, CC BY-SA or CC0. JSON

7 later papers by other authors are listed below: 2 used its method or tool, 4 used its data or values and 1 compared its own results with it.

Uses its method or tool 2 of 13 papers with this label

The solid blue curve indicates the theoretical prediction of $σ(→)$ and $σ(→ℓ)$, calculated at LO except for the pair production of , computed using NLO quantum chromodynamics corrections [ref] and the model implementation in Ref. [ref] .

Search for singly and pair-produced leptoquarks coupling to third-generation fermions in proton-proton collisions at $\sqrt{s} =$ 13 TeV (2020) · Results · 0.97
Used the code of this paper to calculate next-to-leading-order theoretical predictions for leptoquark pair production.

The Case for Future Hadron Colliders From $B \to K^{(*)} \mu^+ \mu^-$ Decays (2017) · 1.00 · paraphrased: the licence does not allow quoting

Uses its data or values 4 of 11 papers with this label

Took its next-to-leading-order pair production cross sections and associated uncertainties at 8 TeV from the calculation presented in this paper.

Search for third-generation scalar leptoquarks in the t-tau channel in proton-proton collisions at sqrt(s) = 8 TeV (2015) · 0.99 · paraphrased: the licence does not allow quoting
Used this paper's next-to-leading-order production cross section of 13.2 fb for a 650 GeV leptoquark to estimate signal acceptances.

Signatures of Leptoquarks at the LHC and Right-handed Neutrinos (2015) · 1.00 · paraphrased: the licence does not allow quoting
The NLO $K$-factor for the QCD pair production channel is obtained by comparing the LO cross-sections with the NLO prediction [ref] .

Lepton Number Violation at the LHC in Radiative Neutrino Mass Models with Leptoquarks (2025) · Analysis · 0.89
Assumed the ratios of next-to-leading-order to leading-order cross sections for vector leptoquarks are the same as this paper's scalar leptoquark ratios, which vary from 1.62 to 4.03 over the 300 to 1800 mass range.

Search for pair production of first and second generation leptoquarks in proton-proton collisions at sqrt(s) = 8 TeV (2015) · 0.89 · paraphrased: the licence does not allow quoting

Compares with it 1 of 6 papers with this label

Reported that its own fixed-order next-to-leading-order results are in extremely good agreement with the next-to-leading-order results already available in this paper.

Pair Production of Scalar Leptoquarks at the LHC to NLO Parton Shower Accuracy (2015) · 0.94 · paraphrased: the licence does not allow quoting

How the literature uses it

71 arXiv papers cite this in 94 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 · 54 sentences without a confident label

Uses its method or tool 11 papers

The scalar LQ pair production cross sections are calculated with using the tool from Ref. [ref] with NLO QCD corrections [ref] and the PDF4LHC15 [ref] NLO PDF set, and are used for comparison with data and background estimations in the statistical analysis.

Search for pair production of scalar and vector leptoquarks decaying to muons and bottom quarks in proton-proton collisions at $\sqrt{s}$ = 13 TeV · Data and simulated samples · 1.00
Samples used to model the $$ signal were generated at next-to-leading order (NLO) in QCD with 2.6.0 [ref] , using the LQ model of Ref. [ref] that adds parton showers to previous fixed-order NLO QCD calculations [ref] , and the NNPDF 3.0 NLO [ref] parton distribution function (PDF) set.

Search for pair production of third-generation scalar leptoquarks decaying into a top quark and a $\tau$-lepton in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector · Data and simulated event samples · 1.00
Simulated events with pair-produced scalar LQs were generated at next-to-leading-order (NLO) in quantum chromodynamics (QCD) with MadGraph5_aMC@NLO 2.6.0 [ref] , using the method described in Ref. [ref] , in which fixed-order NLO QCD calculations [ref] are interfaced to Pythia 8.230 [ref] for the parton shower (PS) and hadronisation.

Search for leptoquark pair production decaying into $te^- \bar{t}e^+$ or $t\mu^- \bar{t}\mu^+$ in multi-lepton final states in $pp$ collisions at 13 TeV with the ATLAS detector · Data and simulated event samples · 1.00

Uses its data or values 10 papers

The corresponding next-to-leading-order (NLO) pair production cross sections and associated uncertainties at $√(s)=8$are taken from the calculation presented in Ref. [ref] .

Search for third-generation scalar leptoquarks in the t-tau channel in proton-proton collisions at sqrt(s) = 8 TeV · Introduction · 0.99
Since the NLO production cross section for a 650 GeV leptoquark is determined to be $13.2$ fb [ref] , the signal acceptances for the leptoquarks are $48.6$% and $28.8$% for $eejj$ and $eνjj$ [ref] channels, respectively, for the integrated luminosity 19.6 $fb^-1$.

Signatures of Leptoquarks at the LHC and Right-handed Neutrinos · Leptoquark signature at LHC · 1.00
In the signal, we use an average NLO $K_QCD$ factor of $1.58$ [ref] for the sLQ pair production.

Right-handed neutrino production through first-generation leptoquarks · LHC Phenomenology · 1.00

Compares with it 3 papers

This is compared with the NLO predictions [ref] to determine lower limits on $M_LQ$ for $β= 1$ and $β= 0.5$.

Search for pair production of first- and second-generation scalar leptoquarks in pp collisions at sqrt(s) = 7 TeV · Introduction · 0.95
Before we present the NLO+PS results in the next section, we note two points in favor of the validity of our setup: (i) we find exact numerical cancellation between the double and single poles coming from the real and virtual parts and (ii) our FO NLO results are in extremely good agreement with the NLO results already available [ref] .

Pair Production of Scalar Leptoquarks at the LHC to NLO Parton Shower Accuracy · NLO+PS Computation · 0.94
Figure [ref] shows the expected and observed limits on the cross section, as well as the theoretical prediction [ref] , as functions of $m()$ and $m()$.

Search for heavy neutrinos and third-generation leptoquarks in hadronic states of two $\tau$ leptons and two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV · Results · 0.82

Cites it as background 14 papers

Previous precision calculation studies for scalar leptoquark pair production rely either on the NLO-QCD computations [ref] , i.e. the contributions of class (1), or on their matching with parton showers [ref] .

Scalar leptoquark pair production at the LHC: precision predictions in the era of flavour anomalies · Scalar leptoquark pair production at fixed order in perturbation theory · 0.93
The phenomenology of leptoquark models has been studied in literature [ref] , specially in the context of the Large Hadron Collider (LHC) experiment.

Phenomenology of Scalar Leptoquarks at the LHC in Explaining the Radiative Neutrino Mass, Muon $g-2$ and Lepton Flavour Violating Observables · Introduction · 0.94
(For a sample of the leptoquark pair production search results, see Refs. [ref] .) The leptoquark pair production cross sections applicable to LHC are accordingly available at the next-to-leading order [ref] as well as the next-to-next-to-leading order [ref] in strong coupling constant, and, more recently, at the next-to-leading order in both the strong coupling constant and the leptoquark Yukawa coupling(s) [ref] .

Asymmetric Leptoquark Pair Production at LHC · Introduction · 0.88

Discussion

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