Аннотации:
are discussing a scenario where a compact
star (neutron star, NS) is embedded in a thin, uniform density background cloud (a remnant cloud after a supernova or
a cloud generated from the late stages of a star e.g., a planetary nebula or asymptotic red giant phases) and its effect on
the stability of the compact star. Due to the thin background
cloud, the spacetime geometry is minimally deformed allowing us to employ the technique of minimal geometric decoupling (MGD). Assuming a uniform background cloud density simplifies the problem, and through the MGD method,
one can take t
t = > 0, where is the density of the
cloud. The background cloud interacts with the compact star
through a coupling strength α. By varying α, one can tune the
cloud density to analyze the stability of the embedded compact star. We found that for α < 3 × 10−5, all the thermodynamic quantities are well-behaved, indicating a stable configuration. Once the coupling parameter exceeds 3 × 10−5, the
adiabatic index drops below
max, triggering a gravitational
collapse. Beyond this limit of α, the pressure and speed of
sound also become non-physical. At the end, we have used
the M −R curve generated from the solution to determine the
radii of a few compact stars, namely PSR J1614-2230, PSR
J0952-0607, GW190814, and GW200210. Furthermore, we
have discussed the possibility of the secondary component
of GW200210 i.e. the less massive compact object with an upper mass of 3.3M , which may be a stellar black hole
with a Schwarzschild radius RBH = 9.746 km. However, if
the mass is 2.83M as observed, then its predicted minimum
radius is 10.74 km, corresponding to α = 0. This radius is
far beyond RBH = 8.357 km and therefore is most probably
a massive NS in the mass gap.
