002798095 001__ 2798095
002798095 005__ 20240729040019.0
002798095 0248_ $$aoai:cds.cern.ch:2798095$$pcerncds:FULLTEXT$$pcerncds:CERN:FULLTEXT$$pcerncds:CERN
002798095 0247_ $$2DOI$$9Springer$$a10.1007/JHEP04(2022)123
002798095 037__ $$9arXiv$$aarXiv:2112.06729$$chep-ph
002798095 037__ $$9arXiv:reportnumber$$aKCL-PH-TH/2021-95
002798095 037__ $$9arXiv:reportnumber$$aCERN-TH-2021-215
002798095 035__ $$9arXiv$$aoai:arXiv.org:2112.06729
002798095 035__ $$9Inspire$$aoai:inspirehep.net:1988998$$d2024-07-28T12:24:21Z$$h2024-07-29T02:00:06Z$$mmarcxml$$ttrue$$uhttps://inspirehep.net/api/oai2d
002798095 035__ $$9Inspire$$a1988998
002798095 041__ $$aeng
002798095 100__ $$aEllis, John$$mjohn.ellis@cern.ch$$tGRID:grid.13097.3c$$tGRID:grid.9132.9$$tGRID:grid.177284.f$$uKing's Coll. London$$uCERN$$uNICPB, Tallinn$$vDepartment of Physics, King’s College London, Strand, WC2R 2LS London, UK$$vTheoretical Physics Department, CERN, Esplanade des Particules 1, CH-1211 Geneva 23, Switzerland$$vNational Institute of Chemical Physics & Biophysics, Rävala 10, 10143 Tallinn, Estonia
002798095 245__ $$9Springer$$aHadron collider probes of the quartic couplings of gluons to the photon and $Z$ boson
002798095 246__ $$9arXiv$$aHadron Collider Probes of the Quartic Couplings of Gluons to the Photon and Z Bosons
002798095 269__ $$c2021-12-13
002798095 260__ $$c2022-04-21
002798095 300__ $$a28 p
002798095 500__ $$9arXiv$$a25 pages, 25 figures; part of the results were talked at CLHCP2021:
https://indico.ihep.ac.cn/event/14560/session/6/contribution/113; v2, Fig.9
is updated by including combined results. 1 table is added; v3, several typos
are corrected; v4, match to published version
002798095 520__ $$9Springer$$aWe explore the experimental sensitivities of measuring the gg → Zγ process at the LHC to the dimension-8 quartic couplings of gluon pairs to the Z boson and photon, in addition to comparing them with the analogous sensitivities in the gg → γγ process. These processes can both receive contributions from 4 different CP-conserving dimension-8 operators with distinct Lorentz structures that contain a pair of gluon field strengths, $ {\hat{G}}_{\mu v}^a $, and a pair of electroweak SU(2) gauge field strengths, $ {W}_{\mu v}^i $, as well as 4 similar operators containing a pair of $ {\hat{G}}_{\mu v}^a $ and a pair of U(1) gauge field strengths, B$_{μν}$. We calculate the scattering angular distributions for gg → Zγ and the Z → $ \overline{f}f $ decay angular distributions for these 4 Lorentz structures, as well as the Standard Model background. We analyze the sensitivity of ATLAS measurements of the Z(→ ℓ$^{+}$ℓ$^{−}$,$ \overline{\nu}\nu $,$ \overline{q}q $)γ final states with integrated luminosities up to 139 fb$^{−1}$ at $ \sqrt{s} $ = 13 TeV, showing that they exclude values ≲ 2 TeV for the dimension-8 operator scales, and compare the Zγ sensitivity with that of an ATLAS measurement of the γγ final state. We present combined Zγ and γγ constraints on the scales of dimension-8 SMEFT operators and γγ constraints on the nonlinearity scale of the Born-Infeld extension of the Standard Model. We also estimate the sensitivities to dimension-8 operators of experiments at possible future proton-proton colliders with centre-of-mass energies of 25, 50 and 100 TeV, and discuss possible measurements of the Z spin and angular correlations.
002798095 520__ $$9arXiv$$aWe explore the experimental sensitivities of measuring the $gg \rightarrow Z \gamma$ process at the LHC to the dimension-8 quartic couplings of gluon pairs to the $Z$ boson and photon, in addition to comparing them with the analogous sensitivities in the $gg \to \gamma \gamma$ process. These processes can both receive contributions from 4 different CP-conserving dimension-8 operators with distinct Lorentz structures that contain a pair of gluon field strengths, $\hat G^a_{\mu \nu}$, and a pair of electroweak SU(2) gauge field strengths, $W^i_{\mu \nu}$, as well as 4 similar operators containing a pair of $\hat G^a_{\mu \nu}$ and a pair of U(1) gauge field strengths, $B_{\mu \nu}$. We calculate the scattering angular distributions for $gg \rightarrow Z \gamma$ and the $Z \to \bar f f$ decay angular distributions for these 4 Lorentz structures, as well as the Standard Model background. We analyze the sensitivity of ATLAS measurements of the $Z(\to \ell^+\ell^-, \bar \nu \nu, \bar q q)\gamma$ final states with integrated luminosities up to 139 fb$^{-1}$ at $\sqrt{s} = 13$ TeV, showing that they exclude values $\lesssim 2$ TeV for the dimension-8 operator scales, and compare the $Z \gamma$ sensitivity with that of an ATLAS measurement of the $\gamma \gamma$ final state. We present combined $Z \gamma$ and $\gamma \gamma$ constraints on the scales of dimension-8 SMEFT operators and $\gamma \gamma$ constraints on the nonlinearity scale of the Born-Infeld extension of the Standard Model. We also estimate the sensitivities to dimension-8 operators of experiments at possible future proton-proton colliders with centre-of-mass energies of 25, 50 and 100 TeV, and discuss possible measurements of the $Z$ spin and angular correlations.
002798095 540__ $$3preprint$$aarXiv nonexclusive-distrib 1.0$$uhttp://arxiv.org/licenses/nonexclusive-distrib/1.0/
002798095 540__ $$3publication$$aCC-BY-4.0$$bSpringer$$fSCOAP3$$uhttp://creativecommons.org/licenses/by/4.0/
002798095 542__ $$3publication$$dThe Authors$$g2021
002798095 595__ $$aCERN-TH
002798095 65017 $$2arXiv$$ahep-ex
002798095 65017 $$2SzGeCERN$$aParticle Physics - Experiment
002798095 65017 $$2arXiv$$ahep-ph
002798095 65017 $$2SzGeCERN$$aParticle Physics - Phenomenology
002798095 690C_ $$aCERN
002798095 690C_ $$aARTICLE
002798095 700__ $$aGe, Shao-Feng$$tGRID:grid.16821.3c$$uShanghai Jiaotong U.$$uTsung-Dao Lee Inst., Shanghai$$uShanghai Jiao Tong U.$$vTsung-Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University, 200240 Shanghai, China$$vKey Laboratory for Particle Astrophysics and Cosmology (MOE) & Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai Jiao Tong University, 200240 Shanghai, China
002798095 700__ $$aMa, Kai$$jORCID:0000-0001-7119-6117$$mmakai@ucas.ac.cn$$tGRID:grid.410726.6$$tGRID:grid.412500.2$$tGRID:grid.510974.e$$tGRID:grid.16821.3c$$uShanghai Jiaotong U.$$uTsung-Dao Lee Inst., Shanghai$$uHIAS, UCAS, Hangzhou$$uICTP-AP, Beijing$$uShaanxi U. Tech.$$vTsung-Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University, 200240 Shanghai, China$$vSchool of Fundamental Physics and Mathematical Science, Hangzhou Institute for Advanced Study, UCAS, 310024 Zhejiang, Hangzhou, China$$vInternational Centre for Theoretical Physics Asia-Pacific, Beijing/Hangzhou, China$$vDepartment of Physics, Shaanxi University of Technology, 723000 Hanzhong, Shaanxi, China
002798095 773__ $$c123$$pJHEP$$v2204$$y2022
002798095 8564_ $$82342393$$s21365$$uhttps://cds.cern.ch/record/2798095/files/histMasJet.png$$y00012 \it Validations of our simulation of the hadronic decay mode $Z\to q\bar{q}$, assuming a scalar resonance $X$ with mass $m_{X}=1\,\tev$. The left panel shows the invariant mass distribution of a fat jet emerging from the decay of a highly-boosted $Z$-boson while the middle and right panels compare distributions of the invariant mass $m_{J\gamma}$ for the VMass and Else categories.
002798095 8564_ $$82342394$$s14472$$uhttps://cds.cern.ch/record/2798095/files/x-AA-LHC13.png$$y00006 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,i}$ and their Born-Infeld combination in Eq.\,(\ref{LBISM}) at the LHC as functions of the cut-off scales $M_i$. These results are obtained from the $gg \rightarrow \gamma \gamma$ reaction at $\sqrt{s} = 13 \, \tev$ with integrated luminosity $\call=139\fb^{-1}$ observed by ATLAS (left) and $\sqrt{s} = 14 \, \tev$ with $\call=3\ab^{-1}$ at HL-LHC (right).
002798095 8564_ $$82342395$$s21392$$uhttps://cds.cern.ch/record/2798095/files/C-TT-ZA-2L-O2.png$$y00023 \it Contour plots in the plane of the lepton azimuthal angle $\phi_{\ell}^{\star}$ and the $Z$ boson polar angle $\vartheta$ for the gQGC operators $\calo_{gT, (0,4)}$ (upper left), $\calo_{gT,(1,5)}$ (upper right), $\calo_{gT, (2,6)}$ (lower left), and $\calo_{gT, (3,7)}$ (lower right). These results are for a gluon-gluon collision energy $\sqrt{\hat{s}} = 100 \, \gev$.
002798095 8564_ $$82342396$$s21162$$uhttps://cds.cern.ch/record/2798095/files/C-TT-ZA-2L-O3.png$$y00024 \it Contour plots in the plane of the lepton azimuthal angle $\phi_{\ell}^{\star}$ and the $Z$ boson polar angle $\vartheta$ for the gQGC operators $\calo_{gT, (0,4)}$ (upper left), $\calo_{gT,(1,5)}$ (upper right), $\calo_{gT, (2,6)}$ (lower left), and $\calo_{gT, (3,7)}$ (lower right). These results are for a gluon-gluon collision energy $\sqrt{\hat{s}} = 100 \, \gev$.
002798095 8564_ $$82342397$$s8808$$uhttps://cds.cern.ch/record/2798095/files/C-TT-ZA-2L-O0.png$$y00021 \it Contour plots in the plane of the lepton azimuthal angle $\phi_{\ell}^{\star}$ and the $Z$ boson polar angle $\vartheta$ for the gQGC operators $\calo_{gT, (0,4)}$ (upper left), $\calo_{gT,(1,5)}$ (upper right), $\calo_{gT, (2,6)}$ (lower left), and $\calo_{gT, (3,7)}$ (lower right). These results are for a gluon-gluon collision energy $\sqrt{\hat{s}} = 100 \, \gev$.
002798095 8564_ $$82342398$$s32222$$uhttps://cds.cern.ch/record/2798095/files/C-TT-ZA-2L-O1.png$$y00022 \it Contour plots in the plane of the lepton azimuthal angle $\phi_{\ell}^{\star}$ and the $Z$ boson polar angle $\vartheta$ for the gQGC operators $\calo_{gT, (0,4)}$ (upper left), $\calo_{gT,(1,5)}$ (upper right), $\calo_{gT, (2,6)}$ (lower left), and $\calo_{gT, (3,7)}$ (lower right). These results are for a gluon-gluon collision energy $\sqrt{\hat{s}} = 100 \, \gev$.
002798095 8564_ $$82342399$$s12186$$uhttps://cds.cern.ch/record/2798095/files/histTomZA.png$$y00005 \it The normalized event spectra due to the background (black solid line) and gQGC operators (colorful non-solid lines) as functions of the $Z\gamma$ invariant mass $m_{Z\gamma}$ (left) and the photon transverse momentum $p_{T \gamma}$ (right) at the LHC with $\sqrt{s} = 13 \, \tev$. As seen more clearly in the left panel, the total cross sections have been regulated to respect the unitarity constraint.
002798095 8564_ $$82342400$$s20883$$uhttps://cds.cern.ch/record/2798095/files/Kinematics.png$$y00018 \it Kinematic variables for the process $gg \rightarrow Z (f \bar f) \gamma$. The scattering plane is defined by the incoming gluons and outgoing $Z/\gamma$ bosons. The polar angle (scattering angle) of the $Z$ boson is defined as $\vartheta$, $\vec{z}^{\,\ast}$ is defined as the $\hat{z}^\ast$-axis in the rest frame of the $Z$ boson along the direction of the $Z$ boson momentum, and the $\hat{x}^\ast-\hat{z}^\ast$ plane is spanned by the vector $\vec{z}^{\,\ast}$ and the direction of the initial gluon motion. The polar and azimuthal angles of the leptons in the rest frame of the $Z$ boson are $\theta_{\ell}^\ast$ and $\phi_{\ell}^\ast$.
002798095 8564_ $$82342401$$s7139$$uhttps://cds.cern.ch/record/2798095/files/scaleZP2JATLAS.png$$y00013 \it Validations of our simulation of the hadronic decay mode $Z\to q\bar{q}$, assuming a scalar resonance $X$ with mass $m_{X}=1\,\tev$. The left panel shows the invariant mass distribution of a fat jet emerging from the decay of a highly-boosted $Z$-boson while the middle and right panels compare distributions of the invariant mass $m_{J\gamma}$ for the VMass and Else categories.
002798095 8564_ $$82342402$$s1211727$$uhttps://cds.cern.ch/record/2798095/files/2112.06729.pdf$$yFulltext
002798095 8564_ $$82342403$$s7561$$uhttps://cds.cern.ch/record/2798095/files/Polar-ZA-2l-P.png$$y00019 \it The normalized differential cross sections in the polar ($\theta^\star_\ell$) and azimuthal ($\phi^\star_\ell$) angles of the outgoing lepton when the gluon-gluon collision energy $\sqrt{\hat{s}} = 100\,\gev$.
002798095 8564_ $$82342404$$s31282$$uhttps://cds.cern.ch/record/2798095/files/xAll.png$$y00017 \it The 95\% C.L. sensitivities of the various channels at the LHC, HL-LHC and proposed future hadron colliders.
002798095 8564_ $$82342405$$s7297$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2J-LHC13.png$$y00015 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(q\bar q) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=36.1\fb^{-1}$ while the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82342406$$s7978$$uhttps://cds.cern.ch/record/2798095/files/PolarZP100.png$$y00002 \it Distributions in the normalized scattering angle $\cos \vartheta$ for $gg \to Z \gamma$ scattering from the gQGC operators (colorful non-solid curves) and the SM background $q \bar q \rightarrow Z \gamma$ (black solid curve). The energy dependences are seen by comparing the left ($\sqrt{\hat{s}} = 100\,{\rm GeV}$) and right ($\sqrt{\hat{s}} = 1\,{\rm TeV}$) panels.
002798095 8564_ $$82342407$$s12875$$uhttps://cds.cern.ch/record/2798095/files/histMasZA.png$$y00004 \it The normalized event spectra due to the background (black solid line) and gQGC operators (colorful non-solid lines) as functions of the $Z\gamma$ invariant mass $m_{Z\gamma}$ (left) and the photon transverse momentum $p_{T \gamma}$ (right) at the LHC with $\sqrt{s} = 13 \, \tev$. As seen more clearly in the left panel, the total cross sections have been regulated to respect the unitarity constraint.
002798095 8564_ $$82342408$$s15925$$uhttps://cds.cern.ch/record/2798095/files/x-AA-HL-LHC.png$$y00007 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,i}$ and their Born-Infeld combination in Eq.\,(\ref{LBISM}) at the LHC as functions of the cut-off scales $M_i$. These results are obtained from the $gg \rightarrow \gamma \gamma$ reaction at $\sqrt{s} = 13 \, \tev$ with integrated luminosity $\call=139\fb^{-1}$ observed by ATLAS (left) and $\sqrt{s} = 14 \, \tev$ with $\call=3\ab^{-1}$ at HL-LHC (right).
002798095 8564_ $$82342409$$s13112$$uhttps://cds.cern.ch/record/2798095/files/PolarZP.png$$y00003 \it Distributions in the normalized scattering angle $\cos \vartheta$ for $gg \to Z \gamma$ scattering from the gQGC operators (colorful non-solid curves) and the SM background $q \bar q \rightarrow Z \gamma$ (black solid curve). The energy dependences are seen by comparing the left ($\sqrt{\hat{s}} = 100\,{\rm GeV}$) and right ($\sqrt{\hat{s}} = 1\,{\rm TeV}$) panels.
002798095 8564_ $$82342410$$s7045$$uhttps://cds.cern.ch/record/2798095/files/Polar-ZA-2l-A.png$$y00020 \it The normalized differential cross sections in the polar ($\theta^\star_\ell$) and azimuthal ($\phi^\star_\ell$) angles of the outgoing lepton when the gluon-gluon collision energy $\sqrt{\hat{s}} = 100\,\gev$.
002798095 8564_ $$82342411$$s7068$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2N-LHC13.png$$y00010 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(\nu\bar\nu) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=36.1\fb^{-1}$ while the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82342412$$s7194$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2L-HL-LHC.png$$y00009 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(\ell^+ \ell^-) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=139\fb^{-1}$, and the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82342413$$s16542$$uhttps://cds.cern.ch/record/2798095/files/xsPP.png$$y00001 \it The total cross sections for $gg \rightarrow Z \gamma$ (left) and $gg \rightarrow \gamma \gamma$ (right) generated by the different dimension-8 gQGC operators at the parton level (colorful non-solid lines). For illustration, we assume that the scattering amplitudes have equal cut-off scales $M = 1$\,TeV until their respective cross sections reach their unitarity limits, which we assume to be saturated at higher gluon-gluon centre-of-mass energies $\sqrt{\hat s}$. The cross sections for the SM background from $q \bar q$ annihilation are shown as solid black lines.
002798095 8564_ $$82342414$$s6708$$uhttps://cds.cern.ch/record/2798095/files/rec-ZA-2J-ATLAS-ELse.png$$y00014 \it Validations of our simulation of the hadronic decay mode $Z\to q\bar{q}$, assuming a scalar resonance $X$ with mass $m_{X}=1\,\tev$. The left panel shows the invariant mass distribution of a fat jet emerging from the decay of a highly-boosted $Z$-boson while the middle and right panels compare distributions of the invariant mass $m_{J\gamma}$ for the VMass and Else categories.
002798095 8564_ $$82342415$$s7010$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2L-LHC13.png$$y00008 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(\ell^+ \ell^-) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=139\fb^{-1}$, and the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82342416$$s11878$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2J-HL-LHC.png$$y00016 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(q\bar q) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=36.1\fb^{-1}$ while the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82342417$$s13169$$uhttps://cds.cern.ch/record/2798095/files/xsZP.png$$y00000 \it The total cross sections for $gg \rightarrow Z \gamma$ (left) and $gg \rightarrow \gamma \gamma$ (right) generated by the different dimension-8 gQGC operators at the parton level (colorful non-solid lines). For illustration, we assume that the scattering amplitudes have equal cut-off scales $M = 1$\,TeV until their respective cross sections reach their unitarity limits, which we assume to be saturated at higher gluon-gluon centre-of-mass energies $\sqrt{\hat s}$. The cross sections for the SM background from $q \bar q$ annihilation are shown as solid black lines.
002798095 8564_ $$82342418$$s11461$$uhttps://cds.cern.ch/record/2798095/files/x-ZA-2N-HL-LHC.png$$y00011 \it The significances $\sqrt{\Delta \chi^2}$ for probes of the \gred{individual} dimension-8 gQGC operators ${\cal O}_{gT,(i, i+4)}$, where $i = 0,1,2,3$, from the $Z(\nu\bar\nu) \gamma$ channel as functions of the cut-off scales $M_i$. The left panel shows the sensitivities obtained using the current LHC data with $\sqrt{s} = 13\,\tev$ and luminosity $\call=36.1\fb^{-1}$ while the right panel shows the estimated sensitivities for the future HL-LHC with $\sqrt{s} = 14\,\tev$ and $\call=3\ab^{-1}$.
002798095 8564_ $$82344019$$s38345$$uhttps://cds.cern.ch/record/2798095/files/yAll-Com.png$$y00017 \it The 95\% C.L. sensitivities of the various channels at the LHC, HL-LHC and proposed future hadron colliders, with cuts given in Table~\ref{tab:hptc}.
002798095 8564_ $$82364199$$s1484242$$uhttps://cds.cern.ch/record/2798095/files/document.pdf$$yFulltext
002798095 960__ $$a13
002798095 980__ $$aARTICLE