Related papers: Holographic spin alignment for vector mesons
We study the mass spectra and spin alignment of vector meson $J/\psi$ in a thermal magnetized background using a generalized theoretical framework based on gauge/gravity duality. Utilizing a soft wall model for the QGP background and a…
We investigate the behaviour of vector mesons $\rho$, $\phi$, and $J/\Psi$ in both non-rotating and rotating thermal media using the soft-wall holographic QCD model with four flavours. By incorporating anisotropic backgrounds derived from…
This review covers the recent experimental development on spin alignment measurements of $K^{*0}$ and $\phi$ vector mesons in heavy-ion and pp collisions at RHIC and LHC energies. Measurements in $e^+e^-$ collisions at LEP energies are also…
A significant $\phi$-meson global spin alignment ($\rho_{00}$) signal was measured in Au+Au collisions at $\sqrt{s_{NN}}\le62$ GeV. Conventional physics mechanisms such as $s(\bar{s})$ spin polarization fail to accommodate this $\rho_{00}$…
The global spin alignment of the vector meson has been observed in relativistic heavy ion collisions, but is still on hot debates in the theoretical community. Here we propose to apply the light front framework to explain this phenomenon…
Starting with the polarization dependent Wigner function of vector mesons, we derive an expression for the 00-component ($\rho_{00}$) of spin density matrix in terms of the second order gradients of the vector meson distribution functions.…
The spin alignment matrix element rho_{00} for the vector mesons K^{*0} and phi(1020) has been measured in RHIC at central rapidities. These measurements are consistent with the absence of polarization with respect to the reaction plane in…
We propose an improved quark coalescence model for spin alignment of vector mesons by spin density matrix with phase space dependence. Within this model we propose an understanding of spin alignments of vector mesons $\phi$ and $K^{*0}$ in…
We propose a novel mechanism that the spin alignment of vector meson $\phi$ and $K^{*0}$ in most central heavy ion collisions is induced by intrinsic QCD dynamics without external vortical/ magnetic fields. The local spin density…
Polarized quarks and antiquarks in high-energy heavy-ion collisions can lead to the spin alignment of vector mesons formed by quark coalescence. Using the relativistic spin Boltzmann equation for vector mesons derived from Kadanoff-Baym…
We propose an improved quark coalescence model for spin alignment of vector mesons and polarization of baryons by spin density matrix with phase space dependence. The spin density matrix is defined through Wigner functions. Within the model…
We discuss results on the diffractive production of the vector mesons rho, phi and omega reported by the H1 and ZEUS collaborations at HERA. Unique to such studies is the experimental accessibility to the polarization of the vector mesons…
For the photoproduction of vector mesons, all single and double spin observables involving vector meson two-body decays are defined consistently in the $\gamma N$ center of mass. These definitions yield a procedure for extracting physically…
We investigate the spin alignment of vector mesons arising from locally polarized quarks and anti-quarks (local spin alignment) in heavy-ion collisions. We find that $\rho_{00}\neq 1/3$ does not necessarily signal the global polarization of…
As the spin alignment of a vector meson is predicted to be correlated with its spectral properties, we study the spectral properties of the $\phi$ meson using two microscopic Lagrangians based either on chiral effective field theory or the…
Non-central heavy ion collisions generate large orbital angular momentum (OAM), providing opportunities to study spin phenomena such as the global spin alignment of vector mesons. Such studies are expected to reveal properties of the…
Continuing our previous study of Deeply Virtual Meson Production (DVMP) at twist-3 accuracy, we derive compact expressions for all helicity amplitudes. We perform a phenomenological analysis of the helicity-amplitude ratio…
The STAR Collaboration has reported a significant $\phi$-meson global spin alignment ($\rho_{00}$) signal in Au+Au collisions at $\sqrt{s_{NN}}\leq62$ GeV by measuring the polar angle distribution of $\phi$-meson daughters with respect to…
We argue that a detailed analysis of the spin alignement of vector mesons can serve as a probe of two little-understood aspects of spin dynamics in the vortical fluid: The degree of relaxation between vorticity and parton spin polarization,…
We have developed the covariant approach for the partial wave analysis of the radiative decay of the vector meson into two pseudoscalar mesons based on the orbital momentum- intrinsic spin decomposition. This allowed us to include the data…