An HI shell-like structure associated with nova V458 Vulpeculae?

We report the radio detection of a shell-like HI structure in proximity to, and probably associated with, the nova V458 Vul. High spectral resolution observation with the Giant Metrewave Radio Telescope has made it possible to study the detailed kinematics of this broken and expanding shell. Unlike the diffuse Galactic HI emission, this is a single-velocity component emission with significant clumping at ~0.5arcmin scales. The observed narrowlinewidth of~5 kms -1 suggests that the shell consists of mostly cold gas.Assuming a distance of 13 kpc to the system, as quoted in the literature, the estimated HI mass of the nebula is about 25M ⊙. However, there are some indications that the system is closer than 13 kpc. If there is a physical association of the HI structure and the nova system, the asymmetric morphology and the off-centred stellar system indicate past strong interaction of the mass loss in the asymptotic giant branch phase with the surrounding interstellar medium. So far, this is the second example, after GK Per, of a large HI structure associated with a classical nova. © 2012 The Authors. Monthly Notices of the Royal Astronomical Society © 2012 RAS.