On the charge of the Galactic centre black hole

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F18%3A00506316" target="_blank" >RIV/67985815:_____/18:00506316 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1093/mnras/sty2182" target="_blank" >https://doi.org/10.1093/mnras/sty2182</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/sty2182" target="_blank" >10.1093/mnras/sty2182</a>

Result language

angličtina

Original language name

On the charge of the Galactic centre black hole

Original language description

The Galactic centre supermassive black hole (SMBH), in sharp contrast with its complex environment, is characterized by only three classical parameters - mass, spin, and electric charge. Its charge is poorly constrained. It is, however, usually assumed to be zero because of neutralization due to the presence of plasma. We revisit the question of the SMBII charge and put realistic limits on its value, time-scales of charging and discharging, and observable consequences of the potential, small charge associated with the Galactic centre black hole. The electric charge due to classical arguments based on the mass difference between protons and electrons is less than or similar to 10(9) C and is of a transient nature on the viscous time-scale. However, the rotation of a black hole in magnetic field generates electric field due to the twisting of magnetic field lines. This electric field can be associated with induced charge, for which we estimate an upper limit of less than or similar to 10(15) C. Moreover, this charge is most likely positive due to an expected alignment between the magnetic field and the black hole spin. Even a small charge of this order significantly shifts the position of the innermost stable circular orbit (ISCO) of charged particles. In addition, we propose a novel observational test based on the presence of the bremsstrahlung surface brightness decrease, which is more sensitive for smaller unshielded electric charges than the black hole shadow size. Based on this test, the current upper observational limit on the charge of Sgr A* is less than or similar to 3 x 10(8) C.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Monthly Notices of the Royal Astronomical Society

ISSN

1365-2966

e-ISSN

—

Volume of the periodical

480

Issue of the periodical within the volume

4

Country of publishing house

GB - UNITED KINGDOM

Number of pages

16

Pages from-to

4408-4423

UT code for WoS article

000449617100011

EID of the result in the Scopus database

2-s2.0-85055154673