Speaker
Kenji Morita
(Kyoto University)
Description
Fluctuations of conserved charges provide us information on the state of
matter at freeze-out temperature $T$ and baryon chemical potential $\mu$.
Since the underlying multiplicity distribution of the net-baryon number
is related to the canonical partition function $Z(T,V,N)$, one can
construct the partition function $\mathcal{Z}(T,V,\mu)$ as a series of
fugacity [1], $ \mathcal{Z}(T,V,\mu) =
\sum_{N=-N^*}^{N^*}Z(T,V,N)e^{\mu N/T}$,where $N^*$ is maximum baryon number the system can possess.
While one may be able to obtain thermodynamic quantities and
fluctuations from the partition function in this way, this also enables
us to study Yang-Lee zeros, which is the zeros of the partition
functions in complex chemical potential and provides information on the
phase boundary.
In this work, we show that the information on the phase boundary
extracted from Yang-Lee zeros of the truncated partition function is
stable under the truncation up to some orders, by making use of a
chiral random matrix model [2].
We compare the zeros from the exact solution of the model with those
from truncated partition function and from the corresponding Skellam
partition function.
We also show that the behavior of the zeros in the model against the truncation has a
significant difference compared to those from the Skellam partition function.
We also discuss statistics necessary for obtain such zeros in heavy ion
experiments.
1. A.Nakamura and K.Nagata, Nucl.Phys.**A931**, 825 (2014).
2. K.Morita and A.Nakamura, arXiv:1505.05985.
Primary author
Kenji Morita
(Kyoto University)
Co-author
Atsushi Nakamura
(Hiroshima Univ)
