Supermassive Black Holes as Possible Sources of Ultrahigh-energy Cosmic Rays

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F47813059%3A19630%2F20%3AA0000027" target="_blank" >RIV/47813059:19630/20:A0000027 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.3847/1538-4357/ab8ae9/meta" target="_blank" >https://iopscience.iop.org/article/10.3847/1538-4357/ab8ae9/meta</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/ab8ae9" target="_blank" >10.3847/1538-4357/ab8ae9</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Supermassive Black Holes as Possible Sources of Ultrahigh-energy Cosmic Rays

Popis výsledku v původním jazyce

The production and acceleration mechanisms of ultrahigh-energy cosmic rays (UHECRs) of energy &gt;10(20) eV, clearly beyond the GZK cutoff limit, remain unclear, which points to the exotic nature of the phenomena. Recent observations of extragalactic neutrinos may indicate that the source of UHECRs is an extragalactic supermassive black hole (SMBH). We demonstrate that ultraefficient energy extraction from a rotating SMBH driven by the magnetic Penrose process (MPP) could indeed fit the bill. We envision ionization of neutral particles, such as neutron beta decay, skirting close to the black hole horizon that energizes protons to over 10(20) eV for an SMBH of mass 10(9)M(circle dot) and magnetic field 10(4). G. Applied to the Galactic center SMBH, we have a proton energy of order approximate to 10(15.6) eV that coincides with the knee of the cosmic-ray spectra. We show that large gamma(z) factors of high-energy particles along the escaping directions occur only in the presence of an induced charge of the black hole, which is known as the Wald charge in the case of a uniform magnetic field. It is remarkable that the process requires neither an extended acceleration zone nor fine-tuning of accreting-matter parameters. Further, this leads to certain verifiable constraints on the SMBH's mass and magnetic field strength as the source of UHECRs. This clearly makes the ultraefficient regime of the MPP one of the most promising mechanisms for fueling the UHECR powerhouse.

Název v anglickém jazyce

Supermassive Black Holes as Possible Sources of Ultrahigh-energy Cosmic Rays

Popis výsledku anglicky

The production and acceleration mechanisms of ultrahigh-energy cosmic rays (UHECRs) of energy &gt;10(20) eV, clearly beyond the GZK cutoff limit, remain unclear, which points to the exotic nature of the phenomena. Recent observations of extragalactic neutrinos may indicate that the source of UHECRs is an extragalactic supermassive black hole (SMBH). We demonstrate that ultraefficient energy extraction from a rotating SMBH driven by the magnetic Penrose process (MPP) could indeed fit the bill. We envision ionization of neutral particles, such as neutron beta decay, skirting close to the black hole horizon that energizes protons to over 10(20) eV for an SMBH of mass 10(9)M(circle dot) and magnetic field 10(4). G. Applied to the Galactic center SMBH, we have a proton energy of order approximate to 10(15.6) eV that coincides with the knee of the cosmic-ray spectra. We show that large gamma(z) factors of high-energy particles along the escaping directions occur only in the presence of an induced charge of the black hole, which is known as the Wald charge in the case of a uniform magnetic field. It is remarkable that the process requires neither an extended acceleration zone nor fine-tuning of accreting-matter parameters. Further, this leads to certain verifiable constraints on the SMBH's mass and magnetic field strength as the source of UHECRs. This clearly makes the ultraefficient regime of the MPP one of the most promising mechanisms for fueling the UHECR powerhouse.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Astrophysical Journal

ISSN

0004-637X

e-ISSN

1538-4357

Svazek periodika

895

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

11

Strana od-do

„14-1“-„14-11“

Kód UT WoS článku

000559792800001

EID výsledku v databázi Scopus

2-s2.0-85086326132