Related papers: Light-by-light scattering cross-section measuremen…
Elastic light-by-light scattering, $\gamma\gamma\to\gamma\gamma$, can be measured in electromagnetic interactions of lead (Pb) ions at the Large Hadron Collider (LHC) and Future Circular Collider (FCC), using the large (quasi)real photon…
We discuss diphoton semi(exclusive) production in ultraperipheral $PbPb$ collisions at energy of $\sqrt{s_{NN}}=$ 5.5 TeV (LHC). The nuclear calculations are based on equivalent photon approximation in the impact parameter space. The cross…
This paper describes a measurement of light-by-light scattering based on Pb+Pb collision data recorded by the ATLAS experiment during Run 2 of the LHC. The study uses $2.2$ nb$^{-1}$ of integrated luminosity collected in 2015 and 2018 at…
This letter describes the observation of the light-by-light scattering process, $\gamma\gamma\rightarrow\gamma\gamma$, in Pb+Pb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV. The analysis is conducted using a data sample corresponding to…
Evidence for the light-by-light scattering process, $\gamma\gamma$ $\to$ $\gamma\gamma$, in ultraperipheral PbPb collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV is reported. The analysis is conducted using a data sample…
Possibility of PbPb$\to$PbPb$\gamma\gamma$ measurement at smaller (< 5 GeV) diphoton invariant mass will be presented. Analysis focuses only on ultraperipheral heavy-ion collisions. This estimate shows that the $\gamma \gamma \to \gamma…
We calculate cross sections for diphoton production in (semi)exclusive $PbPb$ collisions, relevant for the LHC. The calculation is based on equivalent photon approximation in the impact parameter space. The cross sections for elementary…
Measurements of light-by-light scattering (LbL, $\gamma\gamma$ $\to$ $\gamma\gamma$) and the Breit-Wheeler process (BW, $\gamma\gamma$ $\to$ $\mathrm{e^+e^-}$) are reported in ultraperipheral PbPb collisions at a centre-of-mass energy per…
Elastic light-by-light scattering, $\gamma\gamma\to\gamma\gamma$, is open to study at the Large Hadron Collider thanks to the large quasi-real photon fluxes available in electromagnetic interactions of protons (p) and lead (Pb) ions. The…
We present cross sections for diphoton production in (semi)exclusive $PbPb$ collisions, relevant for the LHC. The calculation is based on equivalent photon approximation in the impact parameter space. The cross sections for elementary…
A first measurement of the ttgamma cross section in pp collisions at the LHC using 1.04 fb^-1 of data taken with the ATLAS detector is presented. A total of 122 candidate events were identified in the single electron and single muon…
Evidence for light-by-light (LbL) scattering, $\gamma\gamma\to\gamma\gamma$, in ultraperipheral PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV is reported. LbL scattering processes are selected in events with just…
Light-by-light scattering ($\gamma\gamma\rightarrow\gamma\gamma$) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large…
We discuss diphoton semi(exclusive) production in ultraperipheral lead-lead collisions at energy of $\sqrt{s_{NN}}$ = 5.5 TeV (LHC) and in proton-proton collisions at $\sqrt{s_{pp}}$ = 7 TeV (LHC) and $\sqrt{s_{pp}}$ = 100 TeV (FCC). The…
The current state-of-the-art theoretical estimations lead to cross-sections for $AA \to \gamma \gamma AA$ which are somewhat smaller than the measured ones by the ATLAS and CMS Collaborations, which motivates the searching and calculation…
The current theoretical estimations lead to cross-sections for $AA \to \gamma \gamma AA$ which are somewhat smaller than the measured ones by the ATLAS and CMS Collaborations, In our recent paper, we estimated the contribution of inelastic…
The production cross section of a top quark pair in association with a photon is measured in proton-proton collisions at a center-of-mass energy of 13 TeV. The data set, corresponding to an integrated luminosity of 137 fb$^{-1}$, was…
Cross-section measurements of the associated production of a top quark pair and a photon ($t\bar{t}\gamma$) are performed with an integrated luminosity of 140 fb$^{-1}$ of proton-proton collisions at a centre-of-mass energy of 13 TeV…
The cross section for coherent $\mathrm{J/}\psi$ photoproduction in Pb-Pb collisions is the sum of two contributions, one from low-, the other from high-energy photon-nucleus interactions. A novel method to disentangle both contributions…
A precise measurement of the total cross section and the coulomb scattering at the LHC requires the observation of elastically scatteredparticles at extremely small angles (14 microrad, -t < 0.01 GeV**2 for the first case; 3 microrad,…