TY  - JOUR
AB  - Ratios of cumulants of conserved net charge fluctuations are sensitive to thedegrees of freedom that are carriers of the corresponding quantum numbers indifferent phases of strong interaction matter. Using lattice QCD with 2+1dynamical flavors and quenched charm quarks we calculate second and fourthorder cumulants of net charm fluctuations and their correlations with otherconserved charges such as net baryon number, electric charge and strangeness.Analyzing appropriate ratios of these cumulants we probe the nature of charmeddegrees of freedom in the vicinity of the QCD chiral crossover region. We showthat for temperatures above the chiral crossover transition temperature,charmed degrees of freedom can no longer be described by an uncorrelated gas ofhadrons. This suggests that the dissociation of open charm hadrons and theemergence of deconfined charm states sets in just near the chiral crossovertransition. Till the crossover region we compare these lattice QCD results withtwo hadron resonance gas models --including only the experimentally establishedcharmed resonances and also including additional states predicted by quarkmodel and lattice QCD calculations. This comparison provides evidence for sofar unobserved charmed hadrons that contribute to the thermodynamics in thecrossover region.
DA  - 2014
DO  - 10.1016/j.physletb.2014.08.034
LA  - eng
M2  - 210
PY  - 2014
SN  - 0370-2693
SP  - 210-215
T2  - Physics Letters B
TI  - The melting and abundance of open charm hadrons
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-26718805
Y2  - 2024-11-22T05:13:45
ER  -