The Investigation of Secondary Compact Object in GW190814 with DDRMF Model 

Hu, Jinniu

To study the compact object observed with a mass of $2.50-2.67~M_\odot$ by LIGO Scientific and Virgo collaborations (LVC) in GW19081, properties of neutron star are systematically calculated within the latest density-dependent relativistic mean-field (DDRMF) parameterizations. The maximum masses of neutron star in DD-MEX and DD-LZ1 sets can be around $2.55~M_\odot$. Their maximum speeds of sound $c_s/c$ are smaller than $\sqrt{0.8}$ at the center of neutron star  and dimensionless tidal deformabilities at $1.4~M_\odot$ are less than $800$. Furthermore, their radii of $1.4 ~M_\odot$ also satisfy the constraint on the observable in mass-radius simultaneous measurements (NICER). Therefore, we conclude that the secondary object in GW190814 may be a neutron star composed of hadron matter from DDRMF models.