J 2019

Stable Schwarzschild stars as black-hole mimickers

KONOPLYA, Roman, Nelson Camilo POSADA AGUIRRE, Zdeněk STUCHLÍK and Olexandr ZHYDENKO

Basic information

Original name

Stable Schwarzschild stars as black-hole mimickers

Authors

KONOPLYA, Roman (804 Ukraine, guarantor, belonging to the institution), Nelson Camilo POSADA AGUIRRE (170 Colombia, belonging to the institution), Zdeněk STUCHLÍK (203 Czech Republic, belonging to the institution) and Olexandr ZHYDENKO (804 Ukraine, belonging to the institution)

Edition

Physical Review D, 2019, 2470-0010

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

RIV identification code

RIV/47813059:19240/19:A0000416

Organization unit

Faculty of Philosophy and Science in Opava

UT WoS

000480609700009

Keywords in English

Schwarzschild star; quasinormal modes; black-hole mimicker; stability

Tags

International impact, Reviewed

Links

GA19-03950S, research and development project.
Změněno: 21/4/2020 10:28, Ing. Petra Skoumalová

Abstract

V originále

The Schwarzschild star is an ultracompact object beyond the Buchdahl limit, which has Schwarzschild geometry outside its surface and positive pressure in the external layer which vanishes at the surface. Recently, it has been shown that the Schwarzschild star is stable against spherically symmetric perturbations. Here we study arbitrary axial nonspherical perturbations and show that the observable quasinormal modes can be as close to the Schwarzschild limit as one wishes, what makes the Schwarzschild star a very good mimicker of a black hole. The decaying time-domain profiles prove that the Schwarzschild star is stable against nonspherical perturbations as well. Another peculiar feature is the absence of echoes at the end of the ringdown. Instead we observe a nonoscillating mode which might belong to the class of algebraically special modes. At asymptotically late times, Schwarzschildian power-law tails dominate in the signal.