HADRON2023

Charm meson and charm-meson molecule in an expanding hadron gas

6 Jun 2023, 15:30

20m

DAD - Room Benvenuto (Genova, Italy)

Contributed Heavy meson spectroscopy Heavy meson spectroscopy

Speaker

Liping He (Universität Bonn)

Description

We study the time evolution of the number of charm mesons after the kinetic freeze-out of the hadron gas produced by a central heavy-ion collision. The $\pi D^{\ast }\to \pi D^{\ast }$ reaction rates have t-channel singularities that give contributions inversely proportional to the thermal width of the $D$.  The ratio of the $D^0$ and $D^{+}$ production rate can differ significantly from those predicted using the measured $D^{\ast }$ branching fractions.
We then study the thermal correction to the propagator of a loosely bound charm-meson molecule in a pion gas to next-to-leading order in the heavy-meson expansion. The correction comes primarily from the complex thermal energy shift of the charm-meson constituents. The remaining correction gives a tiny decrease in the binding energy of the molecule and a tiny change in its thermal width. These results are encouraging for the prospects of observing $X(3872)$ and $T_{cc}^{+}(3875)$ in the expanding hadron gas produced by heavy-ion collisions.

Presentation materials

Charm-LipingHe.pdf

Peer reviewing

Paper

Accepted on 21 Dec 2023 by Mikhail Osipenko

Paper files:

• Charm in hadron gas-LipingHe.tex
• cimento.cls
• charm-by-pion-evolution.pdf
• DDvecbubble-4.pdf
• Charm in hadron gas-LIpingHe.pdf