Abstract
The linearly polarized quasi-real photons from the highly Lorentz-contracted Coulomb fields of relativistic heavy ions can fluctuate to quark-antiquark pairs, scatter off a target nucleus and emerge as vector mesons. In the process, the two colliding nuclei can switch roles to act as photon emitter or target, forming a double-slit interference pattern. The product from photoproduction inherits the photon polarization states, leading to the asymmetries of the decay angular distributions. In this letter, we study the interference effect in polarization dimension from the asymmetries of the decay angular distributions for photoprodution in heavy-ion collisions and find a periodic oscillation with the transverse momentum of vector meson, which could reasonably explain the transverse momentum dependence of the 2nd-order modulation in azimuth for the $\rho^{0}$ decay observed by the STAR collaboration.
Highlights
The double-slit interference experiment plays an essential role in expressing the central puzzle of quantum mechanics—wave-particle complementarity
The double-slit interference effect of photonuclear vector meson production in momentum space has been proposed by Klein and Nystrand [13] and verified by the STAR Collaboration through measurements of the ρ0 in ultraperipheral collisions (UPCs) [14]
The vector meson production from linearly polarized photons possesses a distinctive signature in the asymmetries of the decay angular distributions
Summary
The definition of the x, y, and z axes is described in the text. The z0 axis denotes the beam direction, and the x0 axis represents the linear polarization vector. Polarization space for the vector meson photoproduction in heavy-ion collisions and demonstrate that the signature is a periodic oscillation in asymmetries of the decay angular distributions with transverse momentum. That is to say that the modulations of the decay distribution for vector meson are determined by the anisotropy in its two-dimensional transverse momentum distribution with respect to the impact parameter at leading order. According to Eq (3), the modulation strength factor of vector meson decay to two spinless products, 2hcosð2φÞi, versus transverse momentum (pT) can be extracted from the two-dimensional distribution. With the inputs described before, the cross section and differential distributions for vector meson photoproduction can be calculated and can reasonably describe the measurements from STAR [24,41] and ALICE [42,43]. The predictions for ρ0 → eþ þ e− call for further experimental testing
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
