CKVul: evolving nebula and three curious background stars

Abstract

We analyse the remnants of CK Vul (Nova Vul 1670) using optical imaging and spectroscopy. The imaging, obtained between 1991 and 2010, spans 5.6% of the life-time of the nebula. The flux of the nebula decreased during the last 2 decades. The central source still maintains the ionization of the innermost part of the nebula, but recombination proceeds in more distant parts of the nebula. Surprisingly, we discovered two stars located within 10 arcsec of the expansion centre of the radio emission that are characterized by pronounced long term variations and one star with high proper motion. The high proper motion star is a foreground object, and the two variable stars are background objects. The photometric variations of two variables are induced by a dusty cloud ejected by CK Vul and passing through the line of sight to those stars. The cloud leaves strong lithium absorption in the spectra of the stars. We discuss the nature of the object in terms of recent observations.

Published in MNRAS, available at http://mnras.oxfordjournals.org/cgi/content/abstract/stt426?

References in corpus (4)

• Stellar SEDs from 0.3-2.5 Microns: Tracing the Stellar Locus and Searching for Color Outliers in SDSS and 2MASS
• The enigma of the oldest `nova': the central star and nebula of CK Vul
• The diffusion-induced nova scenario. CK Vul and PB 8 as possible observational counterparts
• The energy source of intermediate luminosity optical transients

Cited by in corpus (17)

• Nuclear ashes and outflow in the eruptive star Nova Vul 1670
• Astronomical detection of a radioactive molecule 26AlF in a remnant of an ancient explosion
• Operation of the jet feedback mechanism (JFM) in intermediate luminosity optical transients (ILOTs)
• Organic molecules, ions, and rare isotopologues in the remnant of the stellar-merger candidate, CK Vulpeculae (Nova 1670)
• Molecular remnant of Nova 1670 (CK Vulpeculae). II. A three-dimensional view on the gas distribution and velocity field
• Luminous Red Nova 2015 in the Galaxy M101
• The Distances of the Galactic Novae
• Molecular remnant of Nova 1670 (CK Vulpeculae): I. Properties and enigmatic origin of the gas
• Infrared spectroscopy of CK Vulpeculae: revealing a remarkably powerful blast from the past
• CK Vul: a smorgasbord of hydrocarbons rules out a 1670 nova (and much else besides)
• Lithium in coalesced non-compact stars
• ALMA reveals the aftermath of a white dwarf--brown dwarf merger in CK Vulpeculae
• Spatio-kinematic models of five nova remnants: correlations between nova shell axial ratio, expansion velocity, and speed class
• Elemental abundances in the remnant of the ancient eruption of CK Vulpeculae
• The H$\alpha$ surface brightness $-$ radius plane as a diagnostic tool for photoionized nebulae
• Was there a (super)nova in 1408?
• Is the nitrogen-rich source PN K4-47 a true planetary nebula?