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On the charge of the Galactic centre black hole

Identifikátory výsledku

  • Kód výsledku v 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>

  • Výsledek na webu

    <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>

Alternativní jazyky

  • Jazyk výsledku

    angličtina

  • Název v původním jazyce

    On the charge of the Galactic centre black hole

  • Popis výsledku v původním jazyce

    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.

  • Název v anglickém jazyce

    On the charge of the Galactic centre black hole

  • Popis výsledku anglicky

    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.

Klasifikace

  • Druh

    J<sub>imp</sub> - Článek v periodiku v databázi Web of Science

  • CEP obor

  • OECD FORD obor

    10308 - Astronomy (including astrophysics,space science)

Návaznosti výsledku

  • Projekt

  • Návaznosti

    I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Ostatní

  • Rok uplatnění

    2018

  • Kód důvěrnosti údajů

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

Údaje specifické pro druh výsledku

  • Název periodika

    Monthly Notices of the Royal Astronomical Society

  • ISSN

    1365-2966

  • e-ISSN

  • Svazek periodika

    480

  • Číslo periodika v rámci svazku

    4

  • Stát vydavatele periodika

    GB - Spojené království Velké Británie a Severního Irska

  • Počet stran výsledku

    16

  • Strana od-do

    4408-4423

  • Kód UT WoS článku

    000449617100011

  • EID výsledku v databázi Scopus

    2-s2.0-85055154673