Speaker
Description
The accuracy of astrophysical observations regarding compact stars are
ahead of a big evolution jump thanks to instruments like NICER [1],
which will increase the accuracy of the measurements. The discovery of
gravitational waves originating from merging neutron stars in this year
(GW170817 [2]) is the first step to use gravitational waves as a probe
for extremely dense nuclear matter.
Despite these developments the masquarade problem still persists in
modeling cold superdense nuclear matter based on compact star
observables. Since many different models yield similar neutron star
parameters only high-precision measurements and theoretical reasons can
exclude models.
In this talk we present a realistic, Walecka-type model where the
bosonic fluctuations are included using the Functional Renormalization
Group (FRG) method in the Local Potential Approximation (LPA), based on
a our technique published previously [3,4]. The thermodynamical
quantities, equation of state (EoS), compressibility are calculated in
different approximations: mean field, 1st order and high order. Based
on these EoS, the properties of the corresponding neutron stars are
also calculated using the Tolman--Oppenheimer--Volkov (TOV) equations.
It is also presented, how calculating quantum corrections in different
approximations change the predicted neutron star parameters like mass,
radius and compactness. These results show, that in the light of the
new developments in astrophysical observations quantum corrections are
approaching the threshold where calculating them will be necessary for
the correct comparison between different models.
References
[1] NASA 2017, Nicer, https://www.nasa.gov/nicer
[2] Ligo/Virgo 2017, Phys. Rev. Lett., 119, 161101
[3] Barnaföldi G. G., Jakovac A., Posfay P., 2017, Phys. Rev., D95,025004
[4] Pósfay P. Barnaföldi G.G., A. Jakovác,
arXiv:1710.05410, arXiv:1610.03674
| Content type | Theory |
|---|---|
| Collaboration | Cost Action CA16214, PHAROS |
| Centralised submission by Collaboration | Presenter name already specified |
