Speaker
Description
HADES provides a large acceptance combined with a high mass-resolution
and therefore allows to study dielectron and hadron production in
heavy-ion collisions with unprecedented precision. With the high
statistics of seven billion Au-Au collisions at 1.23 AGeV recorded in
2012 the investigation of collective effects and particle correlations
is possible with so far unprecedented accuracy.
At low energies v1 and v2, related to directed and elliptic flow, have
been measured at the BEVALAC and SIS18, but so far high-order harmonics
have not been studied. They allow to characterize the properties of
the dense hadronic medium produced in these collisions, such as its
viscosity, and provide thus an important reference to measurements at
higher energies. We will present data on higher-order flow harmonics
(v3 and v4) of protons and first results on multi-particle azimuthal
correlation analyses, which can be utilized to disentangle the
contribution from collective and non-flow process involved in the
dynamical evolution of heavy-ion reactions. Furthermore, data on
directed and elliptic flow of light nuclei will be shown.
Information on radial flow can be obtained from the analysis of
pion HBT-correlations, deuteron coalescence and transverse momentum
spectra of identified particles. We will present new results on these
observables extracted from the HADES data and discuss their
correlations. From these a consisten picture emerges which provides
strong evidence for a substantial radial expansion already at these low
beam energies.
| Content type | Experiment |
|---|---|
| Collaboration | HADES |
| Centralised submission by Collaboration | Presenter name already specified |
