AC3 - Accretion discs and jets |
|
Speaker |
PRADHAN, PARTHA PRATIM |
|
Coauthors |
Parthapratim Pradhan |
| Talk Title |
Circular Geodesics and Paczy\'{n}ski-Witta Potential form for a Scalarized Neutron Star |
|
Abstract |
We present a detailed study of the circular geodesic motion of neutral test particles on the equatorial plane of a spherically symmetric scalarized \emph{neutron star}~(NS). We also examined the stability criteria for massive and massless particles for the said NS by computing the effective potential. We compute the radii of innermost stable circular orbit~(ISCO), marginally bound circular orbit~(MBCO) and circular photon orbit~(CPO). We also derive the \emph{Paczy\'{n}ski-Witta potential} which is so called the \emph{pseudo-Newtonian potential} which is very crucial to analyze the accretion disk properties. By analyzing the null circular geodesics we compute the Lyapunov exponent for the scalarized NS. Moreover, we show that in the \emph{eikonal limit}, the real and imaginary parts of the quasi normal modes~(QNM) of the scalarized NS could be determined in terms of the frequency of the NS and instability time scale of the \emph{unstable circular photon geodesics}. Furthermore, we study the Ba\~{n}ados, Silk and West~(BSW) effect of this scalarized NS. We find that the center-of-mass~(CM) energy of colliding neutral test particles near the surface of the NS have the finite energy. |
|
Talk view |
|
|
|
|