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Frank Petriello

Publications and source records attributed to Frank Petriello.

At least 19 recordsLinked to original sources

Hadronization effects and electroweak contributions in DIS one-jettiness

We study the structure of leading hadronization effects and the contributions of massive electroweak gauge boson exchange in the $τ_1$ and $τ_{1a}$ 1-Jettiness global event shapes for deep inelastic scattering (DIS). The leading hadronization effects in $τ_1$ acquire a non-trivial dependence on the hard scattering kinematics. This kinematic dependence is explicitly calculable, so that the leading hadronization effects in $τ_1$, $τ_{1a}$, and DIS thrust are universal and described by the same underlying shape function. The additional calculable kinematic dependence in $τ_1$ provides an independent lever arm for simultaneously constraining hadronization effects in these observables. We present corresponding results at the N$^3$LL+${\cal O}(α_s^2)$ level of accuracy. We extend previous results by including the contributions mediated by the exchange of the massive $Z$ and $W$ electroweak gauge bosons for neutral current (NC) and charged current (CC) DIS, respectively, including ${\cal O}(α_s)$ QCD corrections to obtain N$^2$LL+${\cal O}(α_s)$ results. We compare theoretical predictions to Pythia simulation and demonstrate the universality of leading hadronization effects across NC and CC DIS processes and a wide range of kinematics relevant to HERA and the EIC.

hep-ph

Universality and Kinematic Dependence of Hadronization Effects in DIS Global Event Shapes

We propose a unified framework for a combined global analysis to constrain leading hadronization effects across the 1-Jettiness class of global event shapes for Deep Inelastic Scattering (DIS). We show that for the subclass of jet-based event shapes where the leading jet direction is determined dynamically event-by-event, the leading hadronization effects can acquire a non-trivial dependence on the hard scattering kinematics. However, this dependence is explicitly calculable, allowing for universality of leading hadronization effects in the 1-Jettiness class. The non-trivial kinematic dependence provides an independent lever arm for simultaneously constraining hadronization effects in the jet-based and DIS thrust event shapes. This universality, combined with the kinematic lever arm, could allow for including the typically ignored peak region, where hadronization effects are most severe, in precision extractions of the strong coupling. We demonstrate the need for such a unified treatment of hadronization effects through comparisons of theoretical predictions with simulation data.

hep-ph

The one-point charge correlator in deep inelastic scattering

In this work, we propose a novel definition of the one-point charge correlator (QC) adapted to the Breit frame in deep-inelastic scattering (DIS). We demonstrate that this observable is infrared and collinear (IRC) safe, ensuring its perturbative calculability. Utilizing soft-collinear effective theory (SCET), we systematically analyze the QC in both the forward and back-to-back limits. In the forward limit, we introduce the nucleon charge correlator as a novel non-perturbative object that encodes the multi-dimensional microscopic structure of the nucleon. In the back-to-back limit, the QC establishes a direct correspondence with transverse momentum-dependent distributions (TMDs), enabling its description within the standard TMD factorization formalism. The singular distributions are derived within SCET and are verified by the full QCD calculations up to $\mathcal{O}(α_s^2)$. The corresponding collinear logarithms are resummed to all orders with the accuracy of NLL (${\cal{O}}(α_s^n L^{n-1})$), while the transverse momentum-dependent logarithms are resummed to all orders with the accuracy of $N^3$LL for the unpolarized distribution and N$^2$LL for the Sivers asymmetry.

hep-ph

Sivers Tomography from Charge and Angle Only

We propose a one-point charge-correlator (OPCC) probe of the Sivers effect in back-to-back deep-inelastic scattering. This measurement uses only the signs and directions of charged tracks, with no calorimetric or particle-identification information required. The observable weights the final state by its electric charge and measures the azimuthal correlation between the charge flow and the transverse spin of the proton. This probe is shown to be IRC finite and admits a factorization involving the usual Sivers distribution and a perturbatively calculable charge-weighted jet function for small transverse seperation $b\ll Λ_{\rm QCD}^{-1}$, with no reliance on non-perturbative fragmentation functions or track functions due to charge conservation. We validate the factorization against the full fixed-order QCD and present resummed predictions at N\(^3\)LL accuracy for the unpolarized distribution and N\(^2\)LL for the Sivers asymmetry. The OPCC provides a theoretically clean and simple experimental measurement, and establishes a charge-and-angle measurement paradigm for spin physics at a future Electron-Ion Collider.

hep-ph

Naive $T$-odd Drell-Yan angular coefficients as a probe of the dimension-8 SMEFT

We propose the ``naive" $T$-odd Collins-Soper moments in the Drell-Yan process as probes of previously unexplored directions in the Standard Model Effective Field Theory (SMEFT) parameter space. We show that the moments $A_6$ and $A_7$ in the high invariant mass and transverse momentum region are sensitive to dimension-8 $CP$-odd semi-leptonic four-fermion operators with an additional gluon field strength tensor. Using the projected integrated luminosity of a future high-luminosity LHC, we show that effective ultraviolet scales in the few-TeV range can be probed with this process.

hep-ph

Single-spin measurements and heavy new physics in the $e^+e^- \to t\bar{t}$ process at an FCC-ee

We investigate the potential of single-spin components of the spin-density matrix in the $e^+ e^- \to t\bar{t}$ process at a future FCC-ee for probing heavy new physics parametrized using the SMEFT framework. We consider the full spectrum of spin observables and the complete angular decomposition of the $t\bar{t}$ production process in our study. We find that single-spin measurements generically provide stronger probes of SMEFT Wilson coefficients than measurements where the $t\bar{t}$ spins are correlated, and that single-spin observables are important for resolving flat directions that can appear in the Wilson-coefficient parameter space.

hep-ph

Renormalization-group running of dimension-8 four-fermion operators in the SMEFT

We compute the renormalization-group equations governing the evolution of dimension-8 four-fermion operators in the Standard Model Effective Field Theory (SMEFT). We describe the calculation and present analytic results for both the full flavor structure of the SMEFT and with the assumption of minimal flavor violation. We present numerical results for the renormalization-group evolution of the coefficients, and study their impact on fits of the Large Hadron Collider (LHC) Drell-Yan data. The effects of running on the dimension-8 coefficients can reach 50\% or more when evolving from 10 TeV scale down to few-GeV energies relevant for the analysis of fixed-target data. However, the impact of the dimension-8 running on the analysis of Drell-Yan data from the LHC is minimal.

hep-ph

EFT Workshop at Notre Dame

The LPC EFT workshop was held April 25-26, 2024 at the University of Notre Dame. The workshop was organized into five thematic sessions: "how far beyond linear" discusses issues of truncation and validity in interpretation of results with an eye towards practicality; "reconstruction-level results" visits the question of how best to design analyses directly targeting inference of EFT parameters; "logistics of combining likelihoods" addresses the challenges of bringing a diverse array of measurements into a cohesive whole; "unfolded results" tackles the question of designing fiducial measurements for later use in EFT interpretations, and the benefits and limitations of unfolding; and "building a sample library" addresses how best to generate simulation samples for use in data analysis. This document serves as a summary of presentations, subsequent discussions, and actionable items identified over the course of the workshop.

hep-ex

Transverse spin asymmetries and the electron Yukawa coupling at an FCC-ee

We show that measurements of single transverse-spin asymmetries at an $e^+e^-$ collider can enhance the sensitivity to the electron Yukawa coupling, possibly enabling observation of the Standard Model value for this quantity. We demonstrate that the significance in both the $b\bar{b}$ and semi-leptonic $WW$ final states can be enhanced by factors of up to three compared to inclusive cross section determinations of this coupling for transversely-polarized electrons. If the positrons can be simultaneously longitudinally polarized, even at the level of 30\%, the significance can be enhanced by a factor of five or more. The method utilizes quantum interference between the Higgs signal and the continuum background and is also applicable in other $WW$ and $ZZ$ final states.

hep-ph

Impact of high invariant-mass Drell-Yan forward-backward asymmetry measurements on SMEFT fits

We study the impact of LHC forward-backward asymmetry (AFB) measurements at high invariant-mass in the Drell-Yan process on probes of semileptonic four-fermion operators in the Standard Model effective field theory (SMEFT). In particular, we study whether AFB measurements can resolve degeneracies in the Wilson coefficient parameter space that appear when considering invariant-mass and rapidity measurements alone. We perform detailed fits of the available high-energy and high-luminosity ATLAS and CMS data for both invariant-mass distributions and AFB. While each type of measurement separately exhibits degeneracies, combining them removes these blind spots in some cases. In other situations it does not, highlighting the importance of incorporating future datasets from other experiments to fully explore this sector of the SMEFT. We investigate the impact of contributions quadratic in the Wilson coefficients on the description of Drell-Yan data and discuss when such terms are important in joint fits of the AFB and invariant-mass data.

hep-ph

Transverse spin asymmetries at the EIC as a probe of anomalous electric and magnetic dipole moments

We show that inclusive single-spin asymmetries (SSAs) with transversely polarized protons or electrons at a future electron ion collider (EIC) are sensitive to new physics contributions to electroweak dipole operators of electrons and quarks. We use the Standard Model Effective Field Theory (SMEFT) to parameterize possible heavy new physics contributions to these couplings. We show that new physics scales at or beyond the TeV-scale can be probed assuming realistic EIC run parameters, and that the transverse spin asymmetries are sensitive to different combinations of the dipole couplings than other measurements such as anomalous magnetic or electric dipole moments. We also study the physics potential of SSAs at a possible future upgrade of the EIC to collide muons and protons. Measurements at such an upgrade could probe the same SMEFT parameters that explain the current anomaly in the muon anomalous magnetic moment, and could also improve current bounds on the muon electric dipole moment.

hep-ph

Theory Techniques for Precision Physics -- Snowmass 2021 TF06 Topical Group Report

The wealth of experimental data collected at laboratory experiments suggests that there is some scale separation between the Standard Model (SM) and phenomena beyond the SM (BSM). New phenomena can manifest itself as small corrections to SM predictions, or as signals in processes where the SM predictions vanish or are exceedingly small. This makes precise calculations of the SM expectations essential, in order to maximize the sensitivity of current and forthcoming experiments to BSM physics. This topical group report highlights some past and forthcoming theory developments critical for maximizing the sensitivity of the experimental program to understanding Nature at the shortest distances.

hep-ph

Exploring the SMEFT at dimension-8 with Drell-Yan transverse momentum measurements

We demonstrate that measurements of the neutral-current Drell-Yan transverse momentum distribution binned in invariant mass are sensitive to unexplored dimension-8 parameters of the Standard Model Effective Field Theory (SMEFT). These distributions are sensitive to four-fermion operators with additional QCD field strength tensors. The determination of the Wilson coefficients of these operators provides a useful diagnostic tool that distinguishes possible ultraviolet completions of the SMEFT. We study how well these effects can be probed by current LHC data, and explore the sensitivity of the future high-luminosity LHC (HL-LHC) to these operators. We find that the HL-LHC data has the potential to strongly probe this sector of the SMEFT.

hep-ph

Neutral-Current Electroweak Physics and SMEFT Studies at the EIC

We study the potential for precision electroweak (EW) measurements and beyond-the-Standard Model (BSM) searches using cross-section asymmetries in neutral-current (NC) deep inelastic scattering at the electron-ion collider (EIC). Our analysis uses a complete and realistic accounting of systematic errors from both theory and experiment and considers the potential of both proton and deuteron beams for a wide range of energies and luminosities. We also consider what can be learned from a possible future positron beam and a potential ten-fold luminosity upgrade of the EIC beyond its initial decade of running. We use the SM effective field theory (SMEFT) framework to parameterize BSM effects and focus on semi-leptonic four-fermion operators, whereas for our precision EW study, we determine how well the EIC can measure the weak mixing angle. New features of our study include the use of an up-to-date detector design of EIC Comprehensive Chromodynamics Experiment (ECCE) and accurate running conditions of the EIC, the simultaneous fitting of beam polarization uncertainties and Wilson coefficients to improve the sensitivity to SMEFT operators, and the inclusion of the weak mixing angle running in our fit template. We find that the EIC can probe BSM operators at scales competitive with and in many cases exceeding LHC Drell-Yan bounds while simultaneously not suffering from degeneracies between Wilson coefficients.

hep-ph

Dilepton production in the SMEFT at $\mathcal O(1/Λ^4)$

We study the inclusion of $\mathcal O(1/Λ^4)$ effects in the Standard Model Effective Field Theory in fits to the current Drell-Yan data at the LHC. Our analysis includes the full set of dimension-6 and dimension-8 operators contributing to the dilepton process, and is performed to next-to-leading-order in the QCD coupling constant at both $\mathcal O(1/Λ^2)$ and $\mathcal O(1/Λ^4)$. We find that the inclusion of dimension-6 squared terms and certain dimension-8 operators has significant effects on fits to the current data. Neglecting them leads to bounds on dimension-6 operators off by large factors. We find that dimension-8 four-fermion operators can already be probed to the several-TeV level by LHC results, and that their inclusion significantly changes the limits found for dimension-6 operators. We discuss which dimension-8 operators should be included in fits to the LHC data. Only a manageable subset of two-derivative dimension-8 four-fermion operators need to be included at this stage given current LHC uncertainties.

hep-ph

Theoretical developments in the SMEFT at dimension-8 and beyond

In this contribution to the Snowmass 2021 process we review theoretical developments in the Standard Model Effective Field Theory (SMEFT) with a focus on effects at the dimension-8 level and beyond. We review the theoretical advances that led to the complete construction of the operator bases for the dimension-8 and dimension-9 SMEFT Lagrangians. We discuss the possibility of obtaining all-orders results in the $1/Λ$ expansion for certain SMEFT observables as well as the current status of renormalization group running and implications for positivity, and briefly present the on-shell approach to constructing SMEFT amplitudes. Finally we present several new phenomenological effects that first arise at dimension-8 and discuss the impact of these terms on experimental analyses.

hep-ph

The Path forward to N$^3$LO

The LHC experiments will achieve percent level precision measurements of processes key to some of the most pressing questions of contemporary particle physics: What is the nature of the Higgs boson? Can we successfully describe the interaction of fundamental particles at high energies? Is there physics beyond the Standard Model at the LHC? The capability to predict and describe such observables at next-to-next-to-next-to-leading order (N$^3$LO) in QCD perturbation theory is paramount to fully exploit these experimental measurements. We describe the current status of N$^3$LO predictions and highlight their importance in the upcoming precision phase of the LHC. Furthermore, we identify key conceptual and mathematical developments necessary to see wide-spread N$^3$LO phenomenology come to fruition.

hep-ph

Removing flat directions in SMEFT fits: how polarized electron-ion collider data can complement the LHC

We study the potential of future Electron-Ion Collider (EIC) data to probe four-fermion operators in the Standard Model Effective Field Theory (SMEFT). The ability to perform measurements with both polarized electron and proton beams at the EIC provides a powerful tool that can disentangle the effects from different SMEFT operators. We compare the potential constraints from an EIC with those obtained from Drell-Yan data at the Large Hadron Collider. We show that EIC data plays an important complementary role since it probes combinations of Wilson coefficients not accessible through available Drell-Yan measurements.

hep-ph