The correlation between vorticity and spin alignment in heavy-ion collisions can be probed through polarization measurements of hadrons, whose total spin originates from both constituent-quark spins and orbital angular momentum in the quark-model framework. So far, experimental measurements have been limited to $\mathrm{\Lambda }$ baryons and vector mesons, whose total spins are composed of quark spins in $s$-wave states within the quark model. Here, as a means to probe the vorticity structure in heavy-ion collisions, we highlight the importance of studying hadrons whose total spin is composed not only of quark spins but also includes contributions from the orbital angular momentum between quarks. To motivate such experimental studies, we calculate the general angular distribution of produced pion in $f_2\left(1270\right)\to \pi +\pi$ using interaction Lagrangian and helicity formalism and check that both methods yield the same result. The distribution is given as a function of angle between pion and initial quantization axis of $f_2$ and the spin-density matrix element of $f_2$. Its diagonal entries and ${\rho }_{20}$ component were computed assuming local thermal equilibrium and blast-wave model for different centrality classes, hence given as a function of azimuthal angle with respect to the impact parameter. This is to set a baseline for future comparison with experiment, as vorticity and spin will, in general, not be in equilibrium.

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• Collective flow
• Particle correlations & fluctuations
• Polarization phenomena
• Relativistic heavy-ion collisions