We investigate the spectral functions of neutral and charged mesons in a hot dense medium under a external magnetic field using the two-flavor quark-meson model within the functional renormalization group framework. Our results show that the spectral functions of $\sigma$ and ${\pi }_0$ mesons develop new structures due to decay channels into quarks occupying different Landau levels. By consistently incorporating the momentum relations at vertices for charged particles in a magnetic field, we further show that the ${\pi }_{+}$ spectral function develops a multipeak structure at finite temperatures, resulting from the various annihilation and decay channels available to ${\pi }_{+}$ in the magnetic environment. This multipeak structure is further enhanced in a finite-density medium, causing the ${\pi }_{+}$ meson to become a broad resonance at lower temperatures and densities compared to neutral mesons. Such a multipeak pattern is expected to be universal for charged mesons under magnetic fields and carries significant implications for understanding transport properties in magnetized strongly interacting fluids.

Close

PrevNext

View figure in article

• Functional renormalization group
• QCD phase transitions
• Quark-gluon plasma
• Relativistic heavy-ion collisions
• Spontaneous symmetry breaking
• Light mesons
• Mesons