Open AccessFurther variability of the compact radio nebula of P Cygni
Author(s) -
Exter K. M.,
Watson S. K.,
Barlow M. J.,
Davis R. J.
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05466.x
Subject(s) - physics , astrophysics , supergiant , flux (metallurgy) , nebula , astronomy , h ii region , resolution (logic) , ionization , stars , star formation , ion , materials science , quantum mechanics , artificial intelligence , computer science , metallurgy
Skinner et al. presented two high‐resolution 6‐cm (5 GHz) images of the B‐supergiant star P Cygni. These show the observed morphology and flux densities to have changed over the intervening month. Following on from this, we present a series of seven high‐resolution 6‐cm images (including re‐reductions of the two from Skinner et al.). These confirm that radio emission from the inner 400 mas of the wind is inhomogeneous, consisting usually of several separated bright spots, and that the total and peak flux densities and the observed morphology vary over all time‐scales sampled. We suggest that recombination in cooling clumps of gas which will decrease the radio emission, followed by the appearance of other ionized clumps, could explain such rapid changes, but detailed models must await further observations.