The prototype X-ray binary GX 339-4: Using TeV γ-rays to assess LMXBs as Galactic cosmic ray accelerators
Journal article, 2022

Since the discovery of cosmic rays (CRs) over a century ago, their origin remains an open question. Galactic CRs with energy up to the knee (1015 eV) are considered to originate from supernova remnants, but this scenario has recently been questioned due to lack of TeV γ-ray counterparts in many cases. Extragalactic CRs, on the other hand, are thought to be associated with accelerated particles in the relativistic jets launched by supermassive accreting black holes at the centre of galaxies. Scaled down versions of such jets have been detected in X-ray binaries hosting a stellar black hole (BHXBs). In this work, we investigate the possibility that the smaller scale jets in transient outbursts of low-mass BHXBs could be sources of Galactic CRs. To better test this scenario, we model the entire electromagnetic spectrum of such sources focusing on the potential TeV regime, using the 'canonical' low-mass BHXB GX 339-4 as a benchmark. Taking into account both the leptonic radiative processes and the γ-rays produced via neutral pion decay from inelastic hadronic interactions, we predict the GeV and TeV γ-ray spectrum of GX 339-4 using lower frequency emission as constraints. Based on this test-case of GX 339-4, we investigate whether other, nearby low-mass BHXBs could be detected by the next-generation very-high-energy γ-ray facility the Cherenkov Telescope Array, which would establish them as additional and numerous potential sources of CRs in the Galaxy.

X-rays: Individual: GX 339-4

Radiation mechanisms: non-thermal

Acceleration of particles

Author

D. Kantzas

Anton Pannekoek Institute for Astronomy

University of Amsterdam

S. Markoff

Anton Pannekoek Institute for Astronomy

University of Amsterdam

M. Lucchini

Anton Pannekoek Institute for Astronomy

Massachusetts Institute of Technology (MIT)

Chiara Ceccobello

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

V. Grinberg

University of Tübingen

European Space Research and Technology Centre (ESA ESTEC)

R. M.T. Connors

California Institute of Technology (Caltech)

P. Uttley

Anton Pannekoek Institute for Astronomy

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 510 4 5187-5198

Subject Categories

Accelerator Physics and Instrumentation

Subatomic Physics

Astronomy, Astrophysics and Cosmology

DOI

10.1093/mnras/stac004

More information

Latest update

9/28/2022