2000/01/28 by R. P. Fender, M. Hendry, M. A. Hendry · 3 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Black hole (networking) #Compact star #Eddington luminosity #Galaxy #Luminosity #Neutron star #Outflow #Physics #Pulsar #Pulsars and Gravitational Waves Research #X-ray binary #X-ray pulsar #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2000.03443.x
published as Mon.Not.Roy.Astron.Soc. 317 (2000) 1 · Accepted for publication in MNRAS
arxiv created 2000/01/28 · openalex publication_date 2000/09/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We summarize all the reported detections of, and upper limits to, the radio emission from persistent (i.e. non-transient) X-ray binaries. A striking result is a common mean observed radio luminosity from the black hole candidates (BHCs) in the low/hard X-ray state and the neutron star Z sources on the horizontal X-ray branch. This implies a common mean intrinsic radio luminosity to within a factor of 25 (or less, if there is significant Doppler boosting of the radio emission). Unless coincidental, these results imply a physical mechanism for jet formation that requires neither a black hole event horizon nor a neutron star surface. As a whole the populations of Atoll and X-ray pulsar systems are less luminous by factors of ≳5 and ≳10 at radio wavelengths than the BHCs and Z sources (while some Atoll sources have been detected, no high-field X-ray pulsar has ever been reliably detected as a radio source). We suggest that all of the persistent BHCs and the Z sources generate, at least sporadically, an outflow with physical dimensions 1012 cm; that is, significantly larger than the binary separations of most of the systems. We compare the physical conditions of accretion in each of the types of persistent X-ray binary and conclude that a relatively low (1010 G) magnetic field associated with the accreting object, and a high (0.1 Eddington) accretion rate and/or dramatic physical change in the accretion flow, are required for formation of a radio-emitting outflow or jet.