Top and beauty synergies in SMEFT-fits at present and future colliders

Bißmann, Stefan; Grunwald, Cornelius; Hiller, Gudrun; Kroeninger, K.

doi:10.1007/jhep06(2021)010

“…The values of the χ 2 for each group of datasets in the top-philic scenario were reported in table 22, where we see that the fit quality is very similar to the fit with the baseline settings. Figure 24 then displays the 95% CL intervals for the EFT coefficients comparing the global fit results with those of the top-philic scenario.…”

Section: The Top-philic Scenariomentioning

confidence: 65%

“…Some of these recent studies have targeted the top quark properties [5][6][7][8], the Higgs and electroweak gauge sector [9][10][11], single and double gauge boson production [12][13][14][15], vector-boson scattering [14,16,17], and flavour and low-energy observables [18][19][20], among several others. Furthermore, analyses that combine the constraints of different groups of processes in the EFT parameter space, such as the Higgs and electroweak sector with the top quark one [21] or top quark data with B-meson observables [22,23], have also been presented. These and related studies demonstrate that a global interpretation of the SMEFT is unavoidable and makes possible benefiting from hitherto unexpected connections, such as the correlation of the LHCb flavour anomalies [24,25] at the B-meson scale with the high-p T tails at the LHC [15,26].…”

Section: Jhep11(2021)089 1 Introductionmentioning

confidence: 99%

Combined SMEFT interpretation of Higgs, diboson, and top quark data from the LHC

Ethier

¹

,

Magni

²

,

Maltoni

³

et al. 2021

J. High Energ. Phys.

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We present a global interpretation of Higgs, diboson, and top quark production and decay measurements from the LHC in the framework of the Standard Model Effective Field Theory (SMEFT) at dimension six. We constrain simultaneously 36 independent directions in its parameter space, and compare the outcome of the global analysis with that from individual and two-parameter fits. Our results are obtained by means of state-of-the-art theoretical calculations for the SM and the EFT cross-sections, and account for both linear and quadratic corrections in the 1/Λ2 expansion. We demonstrate how the inclusion of NLO QCD and $$ \mathcal{O} $$ O (Λ−4) effects is instrumental to accurately map the posterior distributions associated to the fitted Wilson coefficients. We assess the interplay and complementarity between the top quark, Higgs, and diboson measurements, deploy a variety of statistical estimators to quantify the impact of each dataset in the parameter space, and carry out fits in BSM-inspired scenarios such as the top-philic model. Our results represent a stepping stone in the ongoing program of model-independent searches at the LHC from precision measurements, and pave the way towards yet more global SMEFT interpretations extended to other high-pT processes as well as to low-energy observables.

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“…ii) Information on semileptonic 4-fermion operators is improving from rare decay studies at flavor factories LHCb and Belle II, as well as Drell-Yan studies at the LHC. iii) Correlations and synergies across sectors provide a useful and informative path in the present situation without direct observations of BSM physics at colliders, in particular given the hints for new physics in rare B-decays, aka the B-anomalies, see [50] for a recent study connecting top and beauty observables in SMEFT. iv) The first evidence for electronmuon universality violation by LHCb [2] makes further analyses and cross checks of this phenomenon vital.…”

Section: Discussionmentioning

confidence: 99%

“…We find that the limits from dineutrino modes on κ tc L , = e, µ are stronger than the ones with ditops by roughly a factor 5, whereas the ones on κ tu L are comparable. Assuming a top-philic flavor pattern the ditop coupling induces FCNC ones (in the down mass basis), e.g., [50],…”

Section: Charged Dilepton Couplings Bounded By Dineutrino Modesmentioning

confidence: 99%

Interplay of dineutrino modes with semileptonic rare B-decays

Bause

¹

,

Gisbert

²

,

Golz

³

et al. 2021

J. High Energ. Phys.

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We present a systematic global analysis of dineutrino modes b → qν$$ \overline{\nu} $$ ν ¯ , q = d, s, and charged dilepton b → qℓ+ℓ− transitions. We derive improved or even entirely new limits on dineutrino branching ratios including decays B0→ (K0, Xs)ν$$ \overline{\nu} $$ ν ¯ , Bs→ ϕν$$ \overline{\nu} $$ ν ¯ and B0→ (π0, ρ0)ν$$ \overline{\nu} $$ ν ¯ from dineutrino modes which presently are best constrained: B+→ (K+, π+, ρ+)ν$$ \overline{\nu} $$ ν ¯ and B0→ K*0ν$$ \overline{\nu} $$ ν ¯ . Using SMEFT we obtain new flavor constraints from the dineutrino modes, which are stronger than the corresponding ones from charged dilepton rare b-decay or Drell-Yan data, for eτ and ττ final states, as well as for μτ ones in b → s processes. The method also allows to put novel constraints on semileptonic four-fermion operators with top quarks. Implications for ditau modes b → sτ+τ− and b → dτ+τ− are worked out. Even stronger constraints are obtained in simplified BSM frameworks such as leptoquarks and Z′-models. Furthermore, the interplay between dineutrinos and charged dileptons allows for concrete, novel tests of lepton universality in rare B-decays. Performing a global fit to b → sμ+μ−, sγ transitions we find that lepton universality predicts the ratio of the B0→ K*0ν$$ \overline{\nu} $$ ν ¯ to B0→ K0ν$$ \overline{\nu} $$ ν ¯ (B+→ K+ν$$ \overline{\nu} $$ ν ¯ ) branching fractions to be within 1.7 to 2.6 (1.6 to 2.4) at 1σ, a region that includes the standard model, and that can be narrowed with improved charged dilepton data. There is sizable room outside this region where universality is broken and that can be probed with the Belle II experiment. Using results of a fit to B0→ μ+μ−, $$ {B}_s^0 $$ B s 0 →$$ \overline{K} $$ K ¯ *0μ+μ− and B+→ π+μ+μ− data we obtain an analogous relation for |∆b| = |∆d| = 1 transitions: if lepton universality holds the ratio of the B0→ ρ0ν$$ \overline{\nu} $$ ν ¯ to B0→ π0ν$$ \overline{\nu} $$ ν ¯ (B+→ π+ν$$ \overline{\nu} $$ ν ¯ ) branching fractions is within 2.5 to 5.7 (1.2 to 2.6) at 1 σ. Putting upper limits on $$ \mathcal{B} $$ B (Bs→ ν$$ \overline{\nu} $$ ν ¯ ) at the level of 10−5 and $$ \mathcal{B} $$ B (B0→ ν$$ \overline{\nu} $$ ν ¯ ) below 10−6 would allow to control backgrounds from (pseudo-)scalar operators such as those induced by light right-handed neutrinos.

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“…While the collider has now (almost) reached the design energy, its integrated luminosity continues to grow steadily, thus greatly facilitating dedicated studies of the (currently statistics-limited) high-energy tails of distributions. With this motivation, several high-p T LHC cross sections have been studied as indirect probes of new physics in the EFT framework, from the (di)lepton distributions in neutral-and charged-current Drell-Yan (DY) distributions (the main subject of this work) to inclusive jets and dijets [49][50][51][52], top quark pair distributions [53][54][55][56][57][58][59][60][61], gauge boson pair production [61][62][63][64][65][66][67], and vector boson scattering [67][68][69][70], among several others.…”

Section: Introductionmentioning

confidence: 99%

Parton distributions in the SMEFT from high-energy Drell-Yan tails

Greljo

¹

,

Iranipour

²

,

Kassabov

³

et al. 2021

J. High Energ. Phys.

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The high-energy tails of charged- and neutral-current Drell-Yan processes provide important constraints on the light quark and anti-quark parton distribution functions (PDFs) in the large-x region. At the same time, short-distance new physics effects such as those encoded by the Standard Model Effective Field Theory (SMEFT) would induce smooth distortions to the same high-energy Drell-Yan tails. In this work, we assess for the first time the interplay between PDFs and EFT effects for high-mass Drell-Yan processes at the LHC and quantify the impact that the consistent joint determination of PDFs and Wilson coefficients has on the bounds derived for the latter. We consider two well-motivated new physics scenarios: 1) electroweak oblique corrections ($$ \hat{W},\hat{Y} $$ W ̂ , Y ̂ ) and 2) four-fermion interactions potentially related to the LHCb anomalies in R(K(*)). We account for available Drell-Yan data, both from unfolded cross sections and from searches, and carry out dedicated projections for the High-Luminosity LHC. Our main finding is that, while the interplay between PDFs and EFT effects remains moderate for the current dataset, it will become a significant challenge for EFT analyses at the HL-LHC.

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Top and beauty synergies in SMEFT-fits at present and future colliders

Cited by 45 publications

References 105 publications

Combined SMEFT interpretation of Higgs, diboson, and top quark data from the LHC

Combined SMEFT interpretation of Higgs, diboson, and top quark data from the LHC

Interplay of dineutrino modes with semileptonic rare B-decays

Parton distributions in the SMEFT from high-energy Drell-Yan tails

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