A near-infrared catalogue of the Galactic novae in the VVV survey area^⋆

¹ Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago, Chile
e-mail: rsaito@astro.puc.cl
² Departamento de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso, Ave. Gran Bretaña 1111, Playa Ancha, Casilla 5030, Valparaíso, Chile
³ The Milky Way Millennium Nucleus, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago, Chile
⁴ Universidade Federal de Sergipe, Departamento de Física, Av. Marechal Rondon s/n, 49100-000, São Cristóvão, SE, Brazil
⁵ Vatican Observatory, Vatican City State 00120, Italy
⁶ Departamento de Ciencias Fisicas, Universidad Andres Bello, Av. Republica 252, Santiago, Chile
⁷ Department of Electrical Engineering, Center for Astro-Engineering, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago, Chile
⁸ Jodrell Bank Centre for Astrophysics, University of Manchester, Oxford Road, Manchester M13 9PL, UK
⁹ Departamento de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción, Chile

Received: 7 February 2013
Accepted: 5 April 2013

Abstract

Context. Near-infrared data on classical novae contain useful information about the ejected gas mass and the thermal emission by dust formed during eruption, and provide independent methods to classify the objects according to the colour of their progenitors, and the fading rate and features seen after eruption. The VISTA Variables in the Vía Láctea survey (VVV) is a near-IR ESO Public Survey mapping the Milky Way bulge and southern plane. Data taken during 2010–2011 covered the entire area in the JHK_s bands plus some epochs in K_s-band of the ongoing VVV variability campaign.

Aims. We used the VVV data to create a near-IR catalogue of the known Galactic novae in the 562 sq. deg. area covered by VVV. We also compiled the information about novae from the variability tables of the VVV variability campaign.

Methods. We used the novae list provided by VSX/AAVSO catalogue to search for all objects within the VVV area. From the 140 novae, we were able to retrieve the JHK_s colours of 93 objects. We also checked in the ongoing VVV variability campaign for the light curves of novae that erupted in the last years.

Results. The VVV near-IR catalogue of novae contains JHK_s photometry of 93 objects completed as of December 2012. VVV allows to monitor objects within up to ΔK_s ~ 10 mag range. VVV images can also be used to discover and study novae by searching for the expanding shell. Since objects are seen at different distances and reddening levels, the colour–magnitude and colour–colour diagrams show the novae spread in magnitude as well as in colour. Dereddened colours and reddening-free indices were used with caution and cannot be a good approach in all cases since the distance and spectral features prevent more conclusive results for some extreme objects. Light curves for some recent novae are presented.

Conclusions. Thanks to its high spatial resolution in the near IR and wide K_s-range, the VVV survey can be a major contributor to the search for and study of novae in the most crowded and high-extinction regions of the Milky Way. The VVV survey area contains ~35% of all known novae in the Galaxy.