Standard Model Value Research Articles

Frugal U(1)X models with non-minimal flavor violation for b → sℓℓ anomalies and neutrino mixing

We analyze the class of models with an extra U(1)X gauge symmetry that can account for the b → sℓℓ anomalies by modifying the Wilson coefficients C9e and C9μ of the operators {O}_{9mathrm{ell}}equiv left(overline{b}{gamma}_{mu }{P}_Lsright)left(overline{mathrm{ell}}{gamma}^{mu}mathrm{ell}right) from their standard model values. At the same time, these models generate appropriate quark mixing, and give rise to neutrino mixing via the Type-I seesaw mechanism. Apart from the gauge boson Z′, these frugal models only have three right-handed neutrinos for the seesaw mechanism, an additional SU(2)L scalar doublet for quark mixing, and a SM-singlet scalar that breaks the U(1)X symmetry. This set-up identifies a class of leptonic symmetries, and necessitates non-zero but equal charges for the first two quark generations. If the quark mixing beyond the standard model were CKM-like, all these symmetries would be ruled out by the latest flavor constraints on Wilson coefficients and collider constraints on Z′ parameters. However, we identify a single-parameter source of non-minimal flavor violation that allows a wider class of U(1)X symmetries to be compatible with all data. We show that the viable leptonic symmetries have to be of the form Le± 3Lμ− Lτ or Le− 3Lμ + Lτ, and determine the (MZ′, gZ′) parameter space that may be probed by the high-luminosity data at the LHC.

Measuring the electron Yukawa coupling via resonant s-channel Higgs production at FCC-ee

The Future Circular Collider (FCC-ee) offers the unique opportunity of studying the Higgs Yukawa coupling to the electron, y_mathrm {e}, via resonant s-channel production, mathrm {e^+e^-}rightarrow mathrm {H}, in a dedicated run at sqrt{s} = m_mathrm {H}. The signature for direct Higgs production is a small rise in the cross sections for particular final states, consistent with Higgs decays, over the expectations for their occurrence due to Standard Model (SM) background processes involving mathrm {Z}^*, gamma ^*, or t-channel exchanges alone. Performing such a measurement is remarkably challenging for four main reasons. First, the low value of the e^pm mass leads to a tiny y_mathrm {e} coupling and correspondingly small cross section: sigma _mathrm {eerightarrow H} propto m_mathrm {e}^2 = 0.57 fb accounting for initial-state gamma radiation. Second, the mathrm {e^+e^-} beams must be monochromatized such that the spread of their centre-of-mass (c.m.) energy is commensurate with the narrow width of the SM Higgs boson, varGamma _mathrm {H} = 4.1 MeV, while keeping large beam luminosities. Third, the Higgs mass must also be known beforehand with a few-MeV accuracy in order to operate the collider at the resonance peak, sqrt{s} = m_mathrm {H}. Last but not least, the cross sections of the background processes are many orders-of-magnitude larger than those of the Higgs decay signals. A preliminary generator-level study of 11 Higgs decay channels using a multivariate analysis, which exploits boosted decision trees to discriminate signal and background events, identifies two final states as the most promising ones in terms of statistical significance: mathrm {H}rightarrow gg and mathrm {H}rightarrow mathrm {W}mathrm {W}^*!rightarrow ell nu + 2 jets. For a benchmark monochromatization with 4.1-MeV c.m. energy spread (leading to sigma _mathrm {eerightarrow H} = 0.28 fb) and 10 ab^{-1} of integrated luminosity, a 1.3sigma signal significance can be reached, corresponding to an upper limit on the e^pm Yukawa coupling at 1.6 times the SM value: |y_mathrm {e}|<1.6|y^mathrm {textsc {sm}}_mathrm {e}| at 95% confidence level, per FCC-ee interaction point per year. Directions for future improvements of the study are outlined.

Electroweak baryogenesis in aligned two Higgs doublet models

We evaluate the baryon number abundance based on the charge transport scenario of top quarks in the CP-violating two Higgs doublet model, in which Yukawa interactions are aligned to avoid dangerous flavor changing neutral currents, and coupling constants of the lightest Higgs boson with the mass 125 GeV coincide with those in the standard model at tree level to satisfy the current LHC data. In this model, the severe constraint from the electric dipole moment of electrons, which are normally difficult to be satisfied, can be avoided by destructive interferences between CP-violating phases in Yukawa interactions and scalar couplings in the Higgs potential. Viable benchmark scenarios are proposed under the current available data and basic theoretical bounds. We find that the observed baryon number can be reproduced in this model, where masses of additional Higgs bosons are typically 300–400 GeV. Furthermore, it is found that the triple Higgs boson coupling is predicted to be 35–55 % larger than the standard model value.

Feasibility study of tau-lepton anomalous magnetic moment measurements with ultra-peripheral collisions at the LHC

Precision measurements of the anomalous electromagnetic moment of leptons (al) may serve as one of the most promising directions in the search for new physics beyond the Standard Model. While the experimental value of the electron magnetic moment agrees with theoretical predictions with up to 11 significant digits, the muon magnetic moment shows deviations from the Standard Model value at the level of 4.2 sigma, indicating the possible occurrence of new physics effects. Although the aτ of the tau lepton with its heavy mass is expected to be ${{m_\tau ^2} \mathord{\left/ {\vphantom {{m_\tau ^2} {m_\mu ^2}}} \right. \kern-\nulldelimiterspace} {m_\mu ^2}} \approx 280$ times more sensitive to new physics effects than aμ, measurements of this quantity are rare. This is because the standard spin precession methods are not suitable for aτ measurements due to the very short tau lifetime. Ultra-peripheral collisions of heavy ions at the LHC may serve as an alternative tool to measure aτ. In ultra-peripheral collisions, hadronic interactions are strongly suppressed and long-distance electromagnetic processes dominate, providing an environment to study the electromagnetic properties of the tau lepton. The di-tau production process PbPb → PbPbγγ → PbPbττ contains two gamma-tau vertices and hence provides enhanced sensitivity to the anomalous magnetic and electric moments. In this contribution we discuss the feasibility of the aτ measurement in ultraperipheral collisions with the ALICE experiment and present projections of the sensitivity of the measurement for the upcoming heavy ion run in 2022 at LHC.

Impact of b rightarrow s ell ell anomalies on rare charm decays in non-universal Z' models

In this work, we study the impact of b rightarrow s ell ell , B_s - bar{B_s} mixing and neutrino trident measurements on observables in decays induced by c rightarrow u transition in the context of a non-universal Z' model which generates C^{mathrm{NP}}_{9} <0 and C^{mathrm{NP}}_9 = - ,C^{mathrm{NP}}_{10} new physics scenarios at the tree level. We inspect the effects on D^0 rightarrow pi ^0 nu {bar{nu }}, D^+ rightarrow pi ^+ nu {bar{nu }} and B_c rightarrow B^+ nu {bar{nu }} decays which are induced by the quark level transition c rightarrow u nu {bar{nu }}. The fact that the branching ratios of these decays are negligible in the standard model (SM) and the long distance effects are relatively smaller in comparison to their charged dileptons counterparts, they are considered to provide genuine null-tests of SM. Therefore the observation of these modes at the level of current as well as planned experimental sensitivities would imply unambiguous signature of new physics. Using the constraints on Z' couplings coming from a combined fit to b rightarrow s ell ell , varDelta M_s and neutrino trident data, we find that any meaningful enhancement over the SM value is ruled out in the considered framework. The same is true for D - {bar{D}} mixing observable varDelta M_D along with D^0 rightarrow mu ^+ mu ^- and D^+ rightarrow pi ^+ mu ^+ mu ^- decay modes which are induced through c rightarrow u mu ^+ mu ^- transition.

Status of the Fermilab Muon g – 2 Experiment

The muon anomalous magnetic moment, aμ = (g – 2)/2, is a low-energy observable which can be both measured and computed with very high precision, making it an excellent test of the Standard Model (SM) and a sensitive probe of new physics. Recent efforts improved the precision of both the theoretical prediction and the experimental measurement. On the theory side, the Muon g – 2 Theory Initiative, an international team of more than 130 physicists, reached in 2020 a consensus on the SM prediction for aμ. On the experimental side, the E989 Muon g – 2 Collaboration at Fermilab (FNAL) published in April 2021 a new measurement of aμ from the Run-1 dataset (2018) with 0.46 ppm precision, corroborating the previous Brookhaven National Laboratory (BNL) measurement and increasing the discrepancy with the SM value to 4.2 standard deviations. In this paper, I will discuss the experimental setup and report on the current status of the experiment.

Spinning no-scale {mathcal {F}}-SU(5) in the right direction

The Fermi National Accelerator Laboratory (FNAL) recently announced confirmation of the Brookhaven National Lab (BNL) measurements of the g-2 of the muon that uncovered a discrepancy with the theoretically calculated Standard Model value. We suggest an explanation for the combined BNL+FNAL 4.2sigma deviation within the supersymmetric grand unification theory (GUT) model No-Scale {mathcal {F}}-SU(5) supplemented with a string derived TeV-scale extra 10+overline{10} vector-like multiplet and charged vector-like singlet (XE,XE^c), dubbed flippons. We introduced these vector-like particles into No-Scale Flipped SU(5) many years ago, and as a result, the renormalization group equation (RGE) running was immediately shaped to produce a distinctive and rather beneficial two-stage gauge coupling unification process to avoid the Landau pole and lift unification to the string scale, in addition to contributing through 1-loop to the light Higgs boson mass. The flippons have long stood ready to tackle another challenge, and now do so yet again, where the charged vector-like “lepton”/singlet couples with the muon, the supersymmetric down-type Higgs H_d, and a singlet S, using a chirality flip to easily accommodate the muonic g-2 discrepancy in No-Scale {mathcal {F}}-SU(5). Considering the phenomenological success of this string derived model over the prior 11 years that remains accommodative of all presently available LHC limits plus all other experimental constraints, including no fine-tuning, and the fact that for the first time a Starobinsky-like inflationary model consistent with all cosmological data was derived from superstring theory in No-Scale Flipped SU(5), we believe it is imperative to reconcile the BNL+FNAL developments within the model space.

Resolving the (g \u2212 2)\u03bc discrepancy with mathcal{F} \u2013SU(5) intersecting D-branes

A discrepancy between the measured anomalous magnetic moment of the muon (g − 2)μ and computed Standard Model value now stands at a combined 4.2σ following experiments at Brookhaven National Lab (BNL) and the Fermi National Accelerator Laboratory (FNAL). A solution to the disagreement is uncovered in flipped SU(5) with additional TeV-Scale vector-like 10 + overline{mathbf{10}} multiplets and charged singlet derived from local F-Theory, collectively referred to as mathcal{F} –SU(5). Here we engage general No-Scale supersymmetry (SUSY) breaking in mathcal{F} –SU(5) D-brane model building to alleviate the (g −2)μ tension between the Standard Model and observations. A robust ∆aμ(SUSY) is realized via mixing of M5 and M1X at the secondary SU(5) × U(1)X unification scale in mathcal{F} –SU(5) emanating from SU(5) breaking and U(1)X flux effects. Calculations unveil ∆aμ(SUSY) = 19.0–22.3 × 10−10 for gluino masses of M( overset{sim }{g} )= 2.25–2.56 TeV and higgsino dark matter, aptly residing within the BNL+FNAL 1σ mean. This (g − 2)μ favorable region of the model space also generates the correct light Higgs boson mass and branching ratios of companion rare decay processes, and is further consistent with all LHC Run 2 constraints. Finally, we also examine the heavy SUSY Higgs boson in light of recent LHC searches for an extended Higgs sector.

Light inflaton model in a metastable universe

We minimally extend the Standard Model (SM) with a ${\mathrm{Z}}_{2}$ symmetric potential containing a single scalar field, serving as our inflaton with a quartic self-coupling. In the model we have symmetry breaking in both sectors, and with the addition of an inflaton-Higgs portal, the universe is able to efficiently reheat via 2-2 inflaton-Higgs scattering. Assuming that the universe with a positive cosmological constant should be metastable, only one particular symmetry breaking pattern in the vacuum is possible, without the need to finely tune the Higgs quartic self-coupling. Inflatons with masses in the range $O({10}^{\ensuremath{-}3})\ensuremath{\le}{m}_{\ensuremath{\chi}}\ensuremath{\le}{m}_{h}$ and mixing angles that span ${\ensuremath{\theta}}_{m}^{2}=O({10}^{\ensuremath{-}11}--{10}^{\ensuremath{-}2})$ evade all current cosmological, experimental, and stability constraints required for a metastable electroweak vacuum. Upgraded particle physics experiments may be able to probe the parameter space with ${\ensuremath{\theta}}_{m}^{2}\ensuremath{\ge}O({10}^{\ensuremath{-}4})$, where we would observe trilinear Higgs couplings suppressed by up to 2% compared to the SM value. However, to access the parameter space of very weakly coupled inflatons, we rely on the proposals to build experiments that target the hidden sector.

Self-interacting neutrinos, the Hubble parameter tension, and the cosmic microwave background

We perform a comprehensive study of cosmological constraints on nonstandard neutrino self-interactions using cosmic microwave background and baryon acoustic oscillation data. We consider different scenarios for neutrino self-interactions distinguished by the fraction of neutrino states allowed to participate in self-interactions and how the relativistic energy density, ${N}_{\mathrm{eff}}$, is allowed to vary. Specifically, we study cases in which all neutrino states self-interact and ${N}_{\mathrm{eff}}$ varies; two species free-stream, which we show alleviates tension with laboratory constraints, while the energy in the additional interacting states varies; and a variable fraction of neutrinos self-interact with either the total ${N}_{\mathrm{eff}}$ fixed to the Standard Model value or allowed to vary. In no case do we find compelling evidence for new neutrino interactions or nonstandard values of ${N}_{\mathrm{eff}}$. In several cases, we find additional modes with neutrino decoupling occurring at lower redshifts ${z}_{\mathrm{dec}}\ensuremath{\sim}{10}^{3--4}$. We do a careful analysis to examine whether new neutrino self-interactions solve or alleviate the so-called ${H}_{0}$ tension and find that, when all Planck 2018 CMB temperature and polarization data are included, none of these examples eases the tension more than allowing a variable ${N}_{\mathrm{eff}}$ comprised of free-streaming particles. Although we focus on neutrino interactions, these constraints are applicable to any light relic particle.

Implications of new evidence for lepton-universality violation in b→sℓ+ℓ− decays

Motivated by renewed evidence for new physics in $b\ensuremath{\rightarrow}s\ensuremath{\ell}\ensuremath{\ell}$ transitions in the form of LHCb's new measurements of theoretically clean lepton-universality ratios and the purely leptonic ${B}_{s}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ decay, we quantify the combined level of discrepancy with the Standard Model and fit values of short-distance Wilson coefficients. A combination of the clean observables ${R}_{K}$, ${R}_{{K}^{*}}$, and ${B}_{s}\ensuremath{\rightarrow}\ensuremath{\mu}\ensuremath{\mu}$ alone results in a discrepancy with the Standard Model at $4.0\ensuremath{\sigma}$, up from $3.5\ensuremath{\sigma}$ in 2017. One-parameter scenarios with purely left-handed or with purely axial coupling to muons fit the data well and result in a $\ensuremath{\sim}5\ensuremath{\sigma}$ pull from the Standard Model. In a two-parameter fit of new-physics contributions with both vector and axial-vector couplings to muons the allowed region is much more restricted than in 2017, principally due to the much more precise result on ${B}_{s}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$, which probes the axial coupling to muons. Including angular observables data restricts the allowed region further. A by-product of our analysis is an updated average of $\mathrm{BR}({B}_{s}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}})=(2.8\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$.

Semi-secretly interacting Axion-like particle as an explanation of Fermilab muon g − 2 measurement

The muon anomalous magnetic moment measurement has, for more than a decade, been a long-standing anomaly hinting the physics beyond the Standard Model (BSM). The recently announced results from muon g−2 collaboration, corresponding to 3.3σ deviation from Standard Model value (4.2σ in combination with previous measurement) are strengthening the need for new physics coupled to muons. In this letter, we propose a novel scenario in which Standard Model (SM) is augmented by an axion-like particle (ALP) and vector-like fermions. We find that such a model admits an excellent interpretation of recent muon g−2 measurement through quantum process featuring ALP interacting with muons and newly introduced fermions. Previously proposed explanations with ALPs utilize interactions with photons and/or SM fermions. Therefore, in this letter we complement and extend such scenarios. We also discuss collider prospects for the model as well as the possibility that ALP is long lived or stable dark matter (DM) candidate.

Importance of fermion loops in W+W− elastic scattering

We test the assumption that fermion-loop corrections to high energy W+W− scattering are negligible when compared to the boson-loop ones. Indeed, we find that, if the couplings of the interactions deviate from their Standard Model values, fermion-loop corrections can in fact become as important or even greater than boson-loop corrections for some particular regions of the parameter space, and both types of loops should be taken into account. Some preliminary results are shown.

New physics constraints from atomic parity violation in Cs133

Our improved calculation of the nuclear spin-independent parity violating electric dipole transition amplitude ($E1_{PV}$) for $6s ~ ^2S_{1/2} - 7s ~ ^2S_{1/2}$ in $^{133}$Cs in combination with the most accurate (0.3\%) measurement of this quantity yields a new value for the nuclear weak charge $Q_W=-73.71(26)_{ex} (23)_{th}$ against the Standard Model (SM) prediction $Q_W^{\text{SM}}=-73.23(1)$. The advances in our calculation of $E1_{PV}$ have been achieved by using a variant of the perturbed relativistic coupled-cluster theory which treats the contributions of the core, valence and excited states to $E1_{PV}$ on the same footing unlike the previous high precision calculations. Furthermore, this approach resolves the controversy regarding the sign of the core correlation effects. We discuss the implications of the deviation of our result for $Q_W$ from the SM value by considering different scenarios of new physics.

Signature of the 2HDM at Higgs factories

The full one-loop corrections, both the weak and QED corrections, to the process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}Z\ensuremath{\phi}$ ($\ensuremath{\phi}={h}^{0},{H}^{0}$) in the two-Higgs-doublet model (2HDM) at the Higgs factories are presented. Up to the $O({\ensuremath{\alpha}}_{\mathrm{em}})$ level, the virtual corrections are evaluated by using the feynarts/formcalc packages. The real emission corrections are computed using the Feynman Diagram Calculation (FDC) package, and the collinear divergences are regularized by the electron structure functions. Using the feynarts/formcalc and FDC packages, we study the corrections in the Standard Model (SM) and the 2HDM, respectively. Gauge dependence arising in the renormalization of mixing angels is removed by using the pinch technique. After taking into account experimental constraints from the current LHC data, we propose four interesting benchmark scenarios for future colliders. By using these benchmark scenarios, we evaluate the deviation of $\mathrm{\ensuremath{\Delta}}\ensuremath{\sigma}({e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}Z\ensuremath{\phi})$ from their SM values. We also examine Higgs boson decays $\ensuremath{\phi}\ensuremath{\rightarrow}b\overline{b}$ and $\ensuremath{\phi}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$, which can have large electroweak (EW) contributions from triple Higgs couplings which are absent in the SM. It is found that for these benchmark scenarios, both EW and real emission corrections are sizeable and could be measured at future ${e}^{+}{e}^{\ensuremath{-}}$ colliders such as the ILC, CLIC, and CEPC.

CP -violating Higgs boson ditau decays: Baryogenesis and Higgs factories

We demonstrate how probes of $CP$-violating observables in Higgs boson ditau decays at prospective future lepton colliders could provide a test of weak scale baryogenesis with significant discovery potential. Measurements at the Circular Electron Positron Collider, for example, could exclude a $CP$ phase larger than 2.9\ifmmode^\circ\else\textdegree\fi{} (5.6\ifmmode^\circ\else\textdegree\fi{}) at 68% (95%) C.L. assuming the Standard Model value for magnitude of the tau lepton Yukawa coupling. Conversely, this sensitivity would allow for a $5\ensuremath{\sigma}$ discovery for 82% of the $CP$ phase range $[0,2\ensuremath{\pi})$. The reaches of the Future Circular Collider for electrons and positrons (FCC-ee) and International Linear Collider are comparable. As a consequence, future lepton colliders could establish the presence of $CP$ violation required by lepton flavored electroweak baryogenesis with at least $3\ensuremath{\sigma}$ sensitivity. Our results illustrate that Higgs factories are not just precision machines, but can also make $\mathcal{O}(1)$ measurement of the new physics beyond the Standard Model.

Probing non-standard [formula omitted] interaction at the LHC at [formula omitted] TeV

In the detailed probe of Higgs boson properties at the Large Hadron Collider (LHC), and in looking for new physics signatures in the electroweak symmetry breaking sector, the bottom quark Yukawa coupling has a crucial role. We investigate possible departure from the standard model value of bb¯h coupling, phenomenologically expressed in terms of a modification factor αb, in bb¯-associated production of the 125-GeV scalar at the high-luminosity LHC. In a next-to-leading order estimate, we make use of a gradient boosting algorithm to improve the statistical significance upon a cut-based analysis. It is found possible to probe down to αb=3 with more than 5σ significance, with L=3000 fb−1 and s = 13 TeV, while the achievable limit at 95% C.L. is ±1.95. Scale dependence of this limit is also reported.

On the use of the local prior on the absolute magnitude of Type Ia supernovae in cosmological inference

ABSTRACT A dark-energy, which behaves as the cosmological constant until a sudden phantom transition at very low redshift (z &amp;lt; 0.1), seems to solve the &amp;gt;4σ disagreement between the local and high-redshift determinations of the Hubble constant, while maintaining the phenomenological success of the Λ cold dark matter model with respect to the other observables. Here, we show that such a hockey-stick dark energy cannot solve the H0 crisis. The basic reason is that the supernova absolute magnitude MB that is used to derive the local H0 constraint is not compatible with the MB that is necessary to fit supernova, baryon acoustic oscillation, and cosmic microwave background data, and this disagreement is not solved by a sudden phantom transition at very low redshift. We make use of this example to show why it is preferable to adopt in the statistical analyses the prior on MB as an alternative to the prior on H0. The three reasons are: (i) one avoids potential double counting of low-redshift supernovae, (ii) one avoids assuming the validity of cosmography, in particular, fixing the deceleration parameter to the standard model value q0 = −0.55, (iii) one includes in the analysis the fact that MB is constrained by local calibration, an information which would otherwise be neglected in the analysis, biasing both model selection and parameter constraints. We provide the priors on MB relative to the recent Pantheon and DES-SN3YR supernova catalogs. We also provide a Gaussian joint prior on H0 and q0 that generalizes the prior on H0 by Supernova H0 for the Equation of State.

First-order electroweak phase transition from weakly coupled sub-GeV physics and possible connection to fermion flavor

We propose that the dynamics of a scalar $\phi$ of mass $O(10)$ MeV that is weakly coupled to the Higgs can lead to a first order electroweak phase transition, fulfilling a key requirement for baryogenesis. Stability of the model near the weak scale requires a suppressed - possibly vanishing - top Yukawa coupling to the Higgs before the transition which rises to the Standard Model value afterwards. This can be accomplished through the dynamics of $\phi$ via a dimension-5 operator. We conjecture that the entire Standard Model flavor structure could turn on, mutatis mutandis, after the electroweak phase transition, via dimension-5 interactions of $\phi$ suppressed by scales ranging from $O(10^3)$ TeV to near Planck mass. Due to its suppressed couplings, $\phi$ is long-lived and can lead to missing energy signals in rare kaon decays, which can be probed by the KOTO experiment.

Light quark Yukawas in triboson final states

Triple heavy vector boson production, pp → VVV (V = W, Z), has recently been observed for the first time. We propose that precision measurements of this process provide an excellent probe of the first generation light quark Yukawa couplings. Modified quark interactions with the off-shell Higgs in this process lead to a rapid growth of the partonic cross sections with energy, which manifests in an enhanced pT distribution of the final state leptons and quarks. We quantify this effect and estimate the present and future 2σ sensitivity to the up, down, and strange Yukawas. In particular, we find that HL-LHC can reach mathcal{O}(400) sensitivity to the down Yukawa relative to the Standard Model value, improving the current sensitivity in this process by a factor of 10, and which can be further improved to mathcal{O}(30) at FCC-hh. This is competitive with and complementary to constraints from global fits and other on-shell probes of the first generation Yukawas. The triboson sensitivity at HL-LHC corresponds to probing dimension-6 SMEFT operators suppressed by an mathcal{O}(1) TeV scale, similarly to other LHC Higgs probes.