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arXiv · 2011.13151

Coulomb nuclear interference effect in dipion production in ultraperipheral heavy ion collisions

Yoshikazu Hagiwara·Cheng Zhang·Jian Zhou·Ya-jin Zhou
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Abstract

We study exclusive $\pi^+ \pi^-$ pair production near $\rho^0$ resonance peak in ultraperipheral heavy ion collisions. Pion pair can either be produced via two photon fusion process or from the decay of $\rho^0$ in photon-nuclear reaction. At very low pair transverse momentum, the electromagnetic and nuclear amplitudes become comparable. We show that the Coulomb nuclear interference amplitude gives rise to sizable $\cos \phi$ and $\cos 3\phi$ azimuthal asymmetries, which can be used to constrain the phase of the dipole-nucleus scattering amplitude.

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Yoshikazu Hagiwara, Cheng Zhang, Jian Zhou, Ya-jin Zhou. 2020-11-26. Coulomb nuclear interference effect in dipion production in ultraperipheral heavy ion collisions. https://doi.org/10.1103/physrevd.103.074013

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