First measurement of D${}^{\ast +}$ vector spin alignment in Pb$-$Pb collisions at $\sqrt{{\mathbf{s}}_{\mathrm{NN}}}=5.02$ TeV

ALICE Collaboration

The first measurement of prompt D${}^{\ast +}$-meson spin alignment in ultrarelativistic heavy-ion collisions with respect to the direction orthogonal to the reaction plane is presented.…