| Article | |
| Report number | arXiv:2112.06729 ; KCL-PH-TH/2021-95 ; CERN-TH-2021-215 |
| Title | Hadron collider probes of the quartic couplings of gluons to the photon and $Z$ boson |
| Related title | Hadron Collider Probes of the Quartic Couplings of Gluons to the Photon and Z Bosons |
| Author(s) | Ellis, John (King's Coll. London ; CERN ; NICPB, Tallinn) ; Ge, Shao-Feng (Shanghai Jiaotong U. ; Tsung-Dao Lee Inst., Shanghai ; Shanghai Jiao Tong U.) ; Ma, Kai (Shanghai Jiaotong U. ; Tsung-Dao Lee Inst., Shanghai ; HIAS, UCAS, Hangzhou ; ICTP-AP, Beijing ; Shaanxi U. Tech.) |
| Publication | 2022-04-21 |
| Imprint | 2021-12-13 |
| Number of pages | 28 |
| Note | 25 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 |
| In: | JHEP 2204 (2022) 123 |
| DOI | 10.1007/JHEP04(2022)123 |
| Subject category | hep-ex ; Particle Physics - Experiment ; hep-ph ; Particle Physics - Phenomenology |
| Abstract | We 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. |
| Copyright/License | publication: © 2021-2024 The Authors (License: CC-BY-4.0), sponsored by SCOAP³ preprint: (License: arXiv nonexclusive-distrib 1.0) |
Corresponding record in: Inspire
Záznam vytvorený 2021-12-15, zmenený 2024-07-29