2013MNRAS.433.2657R

We present near-infrared spectroscopic and photometric observations of the nova KT Eridani taken during the first 100d following its discovery in 2009 November. The JHK spectra of the object have been taken from the Mount Abu Infrared Observatory using the Near-Infrared Imager/Spectrometer. The spectra, typical of the He/N class novae, show strong Hei emission lines together with Hi and Oi emission features. The Hi, Pa β and Br γ spectral lines and the Hei line at 2.0581µm show broad wings with a relatively narrow central component. The broad wings extend to ∼ 1900kms-1 while the central component has full width at half-maximum (FWHM) of ∼ 2100km s-1. The V and near-infrared JHK light curves show an additional small amplitude outburst near 40days after optical maximum. The distance to the nova d = 6.3±0.1 kpc is derived using the MMRD relation and the estimated value of t2 = 5.7±0.3d. The small value of t2 places KT Eri in the class of very fast novae. Using the value of the distance to the nova d, we estimate the height of the nova to be z = 3.3±0.1 kpc below the Galactic plane. We have also calculated the upper limit for the ejecta mass for KT Eri to be in the range 2.4-7.4 x10-5 M☉. Kinematic evidence is presented from the shape of the line profiles for a possible bipolar flow. We analyse the temporal evolution of the continuum and also discuss the possibility of KT Eri being a recurrent nova.