Coherent $ρ^0$ photoproduction in ultra-peripheral Pb-Pb collisions at $\mathbf{\sqrt{\textit{s}_{\rm NN}}} = 2.76$ TeV

Heavy-ion collisions at the Large Hadron Collider: A review of the results from Run 1

“…Therefore, γA collisions can be studied, in which the nucleus remains intact (coherent production) or gets excited and dissolves but without filling the rapidity gap between the nucleus and the produced particle (incoherent production). ALICE has measured exclusive coherent and incoherent charmonium production [365,366,367] and exclusive coherent ρ 0 production [368], see Fig. 29.…”

“…Right: cross section for coherent exclusive ρ 0 production versus rapidity in ultraperipheral PbPb collisions at 2.76 TeV/nucleon from ALICE, compared to theoretical calculations. Taken from [366] and [368].…”

Mapping color fluctuations in the photon in ultraperipheral heavy ion collisions at the Large Hadron Collider

“…The third effect is the significant suppression of the rate of ρ meson production in the coherent γA → ρA reaction measured in Pb-Pb ultraperipheral collisions (UPCs) at the LHC [22] as compared to the expectations of the vector dominance model combined with the Gribov-Glauber approximation for the photon-nucleus interaction. This was explained in [23] by taking into account the effect of CFs in the photon wave function, which reduce the effective ρ-nucleon cross section by suppressing the overlap of the vector meson and photon wave functions and lead to sizable inelastic (Gribov) nuclear shadowing due to the photon inelastic diffraction into large masses.…”

Diffractive dijet photoproduction in ultraperipheral collisions at the LHC in next-to-leading order QCD

“…During the last decade, UPCs have become an active field of research, driven by experimental results obtained at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), for a recent experimental review see, e.g., [2]. Notable examples of various UPC processes and their analyses include the two-photon production of dilepton pairs [3,4]; light-bylight scattering γγ → γγ and searches for potential physics beyond the Standard Model [5][6][7]; an electromagnetic double-scattering contribution to dimuon pair production in photon-photon scattering [8]; exclusive photoproduction of charmonia in proton-proton [9,10], proton-nucleus [11] and nucleus-nucleus [12][13][14][15] UPCs and of bottomonia in proton-proton [16] and proton-nucleus UPCs [17]; new constraints on the small-x gluon distribution in the proton [18,19] and heavy nuclei [20,21] and the dynamics of strong interactions at high energies in the color dipole framework [22][23][24]; and exclusive photoproduction of ρ mesons on nuclei [25][26][27][28] as well as tests of models of nuclear shadowing [29,30].…”