Gluon polarization contribution to the spin alignment of vector mesons from holography

in both non-rotating and rotating thermal media using the soft-wall holographic QCD model with four flavours. By incorporating anisotropic backgrounds derived from the Einstein-Maxwell-dilaton action, we incorporate rotational effects via a

U(1)

gauge field, and the induced polarization of gluons is described by a rotation dependent dilation field. Spectral function analysis reveals that

\rho

and

\phi

mesons exhibit broad peaks at lower temperatures, indicating their presence in the medium, while these peaks disappear at higher temperatures. Rotation delays this melting process, increasing the dissociation temperature. In contrast, the

J/\Psi

meson, owing to its heavy charm quark content, demonstrating its resilience to thermal effects. We further explore the global spin alignment of these mesons in the event plane frame. For the

\phi

meson, the averaged

\rho_{00}

over the full range of azimuthal angle shows weak temperature dependence at low transverse momentum (

p_T

) but significant suppression at high

p_T

, aligning with experimental observations. Rotation enhances

\rho_{00}

at high

p_T

, a phenomenon attributed to angular momentum transfer via spin-orbit coupling. The

J/\Psi

meson, however, displays insensitivity to temperature and rotation up to

p_T=5

GeV, with a very small suppression observed at higher

p_T

, likely due to its heavy quark nature. Although

\rho

meson spin alignment is not yet experimentally measured, it exhibits behaviour qualitatively similar to the

\phi

meson, with thermal fluctuations dampening alignment and rotation enhancing it.

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