Work

The compact jets of the black hole X-ray binary Swift J1753.5-0127 during its 2023-2024 outburst

Year: 2026

Type: article

Abstract: X-ray binaries are excellent laboratories to study the coupling between accretion and ejection phenomena around compact objects through multiwavelength observations. Swift J1753.5--0127 is a black hole low-mass X-ray binary discovered in outburst in 2005 that remained active for 11 years, followed by two mini-outbursts. This X-ray transient is known for exhibiting hard-only outbursts and was one of the first outliers of the radio/X-ray correlation. We investigate the behavior of the compact jets of Swift J1753.5--0127 during its 2023-2024 outburst. We report a dense multiwavelength monitoring in the radio (MeerKAT, AMI--LA), NIR/optical/UV (REM, LCO, ATLAS, /UVOT), and X-ray ( /XRT, NICER/XTI, INTEGRAL/IBIS) bands. Using new and archival luminosity measurements, we construct a refined, smoother radio/X-ray plane that covers the outlier (steep) and transition (shallow) branches of the radio/X-ray correlation. We also present spectral energy distributions (SEDs) constructed using quasi-simultaneous observations from four epochs. Swift Swift Swift J1753.5--0127 underwent a faint, hard-only, double-peaked outburst, followed by a rebrightening in the optical. The updated radio/X-ray plane offers a clear view of the region occupied by this source, similar to MAXI J1348--630, but at radio luminosities lower than H 1743--322, and we confirm its hybrid behavior. The broadband SED fitting reveals that a cool, truncated accretion disk dominates the NIR/optical/UV band. We find that the compact jets have a variable but weak contribution in the NIR, with a break frequency ν_ łesssim 5 break 10^ 12 Hz (łesssim 2 10^ 13 Hz if they do not contribute to the hard X-rays), in line with previous studies, providing additional evidence that radio-quiet sources are also infrared-quiet. We also find evidence that the radio spectral index evolves with X-ray luminosity, transitioning from inverted values near quiescence to flatter or negative values at higher luminosities. In the context of adiabatic jet models, this trend may indicate that jet geometry becomes increasingly confined as the accretion rate rises.

Source: Astronomy and Astrophysics

DOI: 10.1051/0004-6361/202661623