ALMA Data Show 0.5-pc Filaments as Microquasar Jet Footprints in HESS J1023-575
ALMA resolves filamentary CO structures aligned with microquasar jets around HESS J1023-575, implying sustained cosmic-ray acceleration over Myr timescales with energy output far exceeding typical SNRs. The model explains east-west asymmetry via differing HI densities but requires confirmation of the central engine. Preprint evidence is morphological and model-dependent.
The ALMA observations resolve the eastern Jet and western Arc CO clouds into numerous 0.5-pc-wide, 10-20-pc-long filaments at 7.5 kpc distance, precisely parallel to the axis defined by the TeV source. Magneto-hydrodynamical modeling attributes the morphological differences between Jet and Arc structures to asymmetric HI densities on either side of a central compact object, with the filaments representing shocked interfaces where jets have swept up neutral gas over Myr timescales.
This hadronic scenario derives the total cosmic-ray proton energy from observed gamma-ray luminosity and target gas density, producing a value ten times higher than those measured in the well-studied SNRs RX J1713.7-3946 and RX J0852.0-4622. The implied acceleration duration of 1-10 Myr positions HESS J1023-575 as equivalent to at least 1000 individual supernova remnants, highlighting microquasars as sustained Galactic cosmic-ray factories rather than transient SNR shocks.
A Myr-old black hole or neutron star at the center remains undetected due to extinction; deeper X-ray or radio searches are required to confirm the engine. The preprint interpretation hinges on the jet model matching filament orientations, but lacks direct kinematic evidence of outflow motion or variability.
Next steps include VLBI proper-motion measurements of the filaments and sensitive hard-X-ray imaging to locate the compact object within the next 3-5 years.
Tsuge et al.: Hard X-ray point source detected above 10^33 erg/s within 4 years confirming compact object
Sources (2)
- [1]Primary Source(https://arxiv.org/abs/2608.14988)
- [2]Supporting Source(https://arxiv.org/abs/astro-ph/0507464)