https://doi.org/10.1140/epja/s10050-021-00619-0
Regular Article - Theoretical Physics
Bayesian analysis of multimessenger M-R data with interpolated hybrid EoS
1
Laboratory of Information Technologies, JINR, 6 Joliot-Curie Str., 141980, Dubna, Russian Federation
2
IT and Computing Division, A. Alikhanyan National Laboratory, 2 Alikhanian Brothers Str., 0036, Yerevan, Armenia
3
Dubna State University, 19 Universitetskaya Str., 141980, Dubna, Russia
4
Institute of Theoretical Physics, University of Wroclaw, 9 M. Borna Sq, 50-204, Wrocław, Poland
5
Bogoliubov Laboratory of Theoretical Physics, JINR, 6 Joliot-Curie Str., 141980, Dubna, Russian Federation
6
National Research Nuclear University (MEPhI), 31 Kashirskoe Hwy, 115409, Moscow, Russian Federation
7
CONICET, Godoy Cruz 2290, Buenos Aires, Argentina
8
Departamento de Física, Comisión Nacional de Energía Atómica, Av. Libertador 8250, (1429), Buenos Aires, Argentina
9
Henryk Niewodniczański Institute of Nuclear Physics, 152 Radzikowskiego Str, 31-342, Kraków, Poland
10
Department of Physics, Yerevan State University, 1 Alex Manoogian Str, 0025, Yerevan, Armenia
11
Theoretical Physics Division, A. Alikhanyan National Laboratory, 2 Alikhanian Brothers Str., 0036, Yerevan, Armenia
12
Peoples’ Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya Str., 117198, Moscow, Russian Federation
b david.blaschke@gmail.com, david.blaschke@uwr.edu.pl
Received:
26
February
2021
Accepted:
26
October
2021
Published online:
29
November
2021
We introduce a family of equations of state (EoS) for hybrid neutron star (NS) matter that is obtained by a two-zone parabolic interpolation between a soft hadronic EoS at low densities and a set of stiff quark matter EoS at high densities within a finite region of chemical potentials 
. Fixing the hadronic EoS as the APR one and choosing the color-superconducting, nonlocal NJL model with two free parameters for the quark phase, we perform Bayesian analyses with this two-parameter family of hybrid EoS. Using three different sets of observational constraints that include the mass of PSR J0740+6620, the tidal deformability for GW170817, and the mass-radius relation for PSR J0030+0451 from NICER as obligatory (set 1), while set 2 uses the possible upper limit on the maximum mass from GW170817 as an additional constraint and set 3 instead of the possibility that the lighter object in the asymmetric binary merger GW190814 is a neutron star. We confirm that in any case, the quark matter phase has to be color superconducting with the dimensionless diquark coupling approximately fulfilling the Fierz relation 
and the most probable solutions exhibiting a proportionality between 
and 
, the coupling of the repulsive vector interaction that is required for a sufficiently large maximum mass. We used the Bayesian analysis to investigate with the method of fictitious measurements the consequences of anticipating different radii for the massive 
PSR J0740+6220 for the most likely equation of state. With the actual outcome of the NICER radius measurement on PSR J0740+6220 we could conclude that for the most likely hybrid star EoS would not support a maximum mass as large as 
so that the event GW190814 was a binary black hole merger.
© The Author(s) 2021
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