Using the (Modified) Matrix Element Method to constrain $L_{\mu }-L_{\tau }$ Interactions

Abstract

In this paper, we explore the discriminatory power of the matrix element method (MEM) in constraining the $L_{\mu }-L_{\tau }$ model at the LHC. The $Z^{\prime }$ gauge boson associated with the spontaneously broken $U(1{)}_{L_{\mu }-L_{\tau }}$ symmetry only interacts with the second and third generation of leptons at tree level, and is thus difficult to produce at the LHC. We argue that the best channels for discovering this $Z^{\prime }$ are in $Z\to 4\mu$ and $2\mu +/E_T$. Both these channels have a large number of kinematic observables, which strongly motivates the usage of a multivariate technique. The MEM is a multivariate analysis that uses the squared matrix element to quantify the likelihood of the testing hypotheses. We find that with $300{\text{fb}}^{-1}$ of integrated luminosity, we are sensitive to the couplings of $g_{Z^{\prime }}\gtrsim 0.002g_1$ and $M_{Z^{\prime }}<20\text{ GeV}$, and $g_{Z^{\prime }}\gtrsim 0.005g_1$ and $20\text{GeV}<M_{Z^{\prime }}<40\text{GeV}$, which is about an order of magnitude improvement over the cut-and-count method for the same amount of data.

24 pages, 9 figures

References in corpus (29)

• PYTHIA 6.4 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Vector boson pair production at the LHC
• Secluded U(1) below the weak scale
• Boosted Decision Trees as an Alternative to Artificial Neural Networks for Particle Identification
• Explaining $h\to {\mu }^{\pm }{\tau }^{\mp }$, $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $B\to K{\mu }^{+}{\mu }^{-}/B\to K{e}^{+}{e}^{-}$ in a two-Higgs-doublet model with gauged $L_{\mu }-L_{\tau }$
• Illuminating Dark Photons with High-Energy Colliders
• Addressing the LHC flavour anomalies with horizontal gauge symmetries
• Search for direct production of charginos, neutralinos and sleptons in final states with two leptons and missing transverse momentum in pp collisions at sqrt(s) = 8 TeV with the ATLAS detector
• Color singlet production at NNLO in MCFM
• Explaining Dark Matter and $B$ Decay Anomalies with an $L_{\mu }-L_{\tau }$ Model
• Search for a muonic dark force at BABAR
• Lepton flavor violating Z' explanation of the muon anomalous magnetic moment
• Higgs $\to \mu \tau$ in Abelian and Non-Abelian Flavor Symmetry Models
• Observation of Single Top Quark Production and Measurement of |Vtb| with CDF
• Detecting the $L_{\mu }-L_{\tau }$ gauge boson at Belle II
• Studies of Boosted Decision Trees for MiniBooNE Particle Identification
• Next-to-leading-order electroweak corrections to the production of four charged leptons at the LHC
• The Matrix Element Method and its Application to Measurements of the Top Quark Mass
• Observation of Z decays to four leptons with the CMS detector at the LHC
• Search for new physics in final states with two opposite-sign, same-flavor leptons, jets, and missing transverse momentum in pp collisions at sqrt(s) = 13 TeV
• Measurement of the 4l Cross Section at the Z Resonance and Determination of the Branching Fraction of Z->4l in pp Collisions at sqrt(s) = 7 and 8 TeV with ATLAS
• Collider limits on leptophilic interactions
• Precise measurement of the top quark mass from lepton+jets events at D0
• Accelerated Matrix Element Method with Parallel Computing
• Reconstruction of the Higgs mass in events with Higgs bosons decaying into a pair of tau leptons using matrix element techniques
• Measurement of the Top Quark Mass Using the Matrix Element Technique in Dilepton Final States
• Matrix Element Method in HEP: Transfer Functions, Efficiencies, and Likelihood Normalization
• The matrix element method at next-to-leading order for arbitrary jet algorithms

Cited by in corpus (11)

• Search for an $L_{\mu }$ $-$ $L_{\tau }$ gauge boson using Z $\to$ 4$\mu$ events in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Minimal Gauged U(1)${}_{L_{\alpha }-L_{\beta }}$ Models Driven into a Corner
• A Light Higgs at the LHC and the B-Anomalies
• Predictions for the neutrino parameters in the minimal model extended by linear combination of U(1)${}_{L_e-L_{\mu }}$, U(1)${}_{L_{\mu }-L_{\tau }}$ and U(1)${}_{B-L}$ gauge symmetries
• Dark Matter in Anomaly-Free Gauge Extensions
• Searching for Flavored Gauge Bosons
• Machine Learning in High Energy Physics Community White Paper
• LHC Constraints on a $(B-L{)}_3$ Gauge Boson
• Search for a new $Z^{\prime }$ gauge boson via the $pp\to W^{\pm (\ast )}\to Z^{\prime }{\mu }^{\pm }\nu \to {\mu }^{\pm }{\mu }^{\mp }{\mu }^{\pm }\nu$ process in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Strategic Plan for a Scientific Software Innovation Institute (S2I2) for High Energy Physics
• Search for the Z boson decay to $\tau \tau \mu \mu$ in proton-proton collisions at $\sqrt{s}$ = 13 TeV