Radio and X-ray variability in the Seyfert galaxy NGC 4051

摘要: We present intensive quasi-simultaneous X-ray and radio monitoring of the narrow line Seyfert 1 galaxy NGC 4051, over a 16-month period in 2000-01. The observations were made with Proportional Counter Array on Rossi Timing Explorer (RXTE) at 8.4 4.8 GHz Very Large (VLA). In band 4051 behaves very much like analogue Galactic black hole binary (GBH) system 'soft state'. such systems, there has so far been no firm evidence for an active, radio-emitting jet those found 'hard-state' GBHs. VLBI show three well-separated compact components almost line. This structure resembles core outer hot spots seen powerful, jet-dominated, extragalactic sources and, although is visible suggests that weak may exist. However it not previously clear whether nucleus currently active any link between emission processes. Radio complicated by presence surrounding extended changing array configurations VLA. Only A configuration reasonably resolved. have carefully removed differing contaminations various arrays. resulting lightcurve shows sign large amplitude variability (i.e. factor 50 per cent) consistent being constant. Within 6 where we greatest sensitivity see marginal similar to 25 cent (similar 0.12 mJy GHz) 2-week time-scale, correlated variations. These percentage variations are 5548, which 10 times brighter. Even if real, less than band. B observations, somewhat reduced, X-ray/radio variability. NGC one decade lower luminosity radio/X-ray/mass fundamental plane jet-dominated hard-state holes, scatter around same order. lack commonly GBHs be explained orientation effects. Another possibility, variability, arises from corona although, case, linear hard explain. combination explain observations.