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We investigate the prospect of an alternative laboratory-based search for the coupling of axions and axion-like particles to photons. Here, the collision of two laser beams resonantly produces axions, and a signal photon is detected after magnetic reconversion, as in light-shining-through-walls (LSW) experiments. Conventional searches, such as LSW or anomalous birefrigence measurements, are most sensitive to axion masses for which substantial coherence can be achieved; this is usually well below optical energies. We find that using currently available high-power laser facilities, the bounds that can be achieved by our approach outperform traditional LSW at axion masses between $0.5-6$ eV, set by the optical laser frequencies and collision angle. These bounds can be further improved through coherent scattering off laser substructures, probing axion-photon couplings down to $g_{agammagamma}sim 10^{-8} {text{GeV}^{-1}}$, comparable with existing CAST bounds. Assuming a day long measurement per angular step, the QCD axion band can be reached.
The high-energy behaviour of the total cross section for highly virtual photons, as predicted by the BFKL equation at next-to-leading order (NLO) in QCD, is presented. The NLO BFKL predictions, improved by the BLM optimal scale setting, are in excell
This paper investigates the electromagnetic production of lepton pairs with low transverse momentum in relativistic heavy ion collisions. We estimate the initial photons transverse momentum contributions by employing models where the average transver
It is pointed out that there exist a few problems to be overcome toward an observable sub-eV QCD axion in superstring compactification. We give a general expression for the axion decay constant. For a large domain wall number $N_{DW}$, the axion deca
We investigate the effects of gluon number fluctuations on the total $gammagamma$, $gamma^*gamma^*$ cross sections and the photon structure function $F_2^gamma(x,Q^2)$. Considering a model which relates the dipole-dipole and dipole-hadron scattering
A review is given on photon-hadron and photon-photon collisions in the ALICE experiment. The physics motivation for studying such reactions is outlined, and the results obtained in proton-lead and lead-lead collisions in Run 1 of the LHC are discusse