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We present multi-epoch near-infrared photo-spectroscopic observations of NovaCephei 2014 and Nova Scorpii 2015, discovered in outburst on 2014 March 8.79 UTand 2015 February 11.84 UT respectively. Nova Cep 2014 shows the conventionalNIR characteristics of a Fe II class nova characterized by strong CI, HI and OI lines, whereas Nova Sco 2015 is shown to belong to the He/N class with strongHe I, HI and OI emission lines. The highlight of the results consists indemonstrating that Nova Sco 2015 is a symbiotic system containing a giantsecondary. Leaving aside the T CrB class of recurrent novae, all of which havegiant donors, Nova Sco 2015 is shown to be only the third classical nova to befound with a giant secondary. The evidence for the symbiotic nature isthree-fold; first is the presence of a strong decelerative shock accompanyingthe passage of the nova's ejecta through the giant's wind, second is theH$\alpha$ excess seen from the system and third is the spectral energydistribution of the secondary in quiescence typical of a cool late type giant.The evolution of the strength and shape of the emission line profiles showsthat the ejecta velocity follows a power law decay with time ($t^{-1.13 \pm0.17}$). A Case B recombination analysis of the H I Brackett lines shows thatthese lines are affected by optical depth effects for both the novae. Usingthis analysis we make estimates for both the novae of the emission measure$n_e^2L$, the electron density $n_e$ and the mass of the ejecta.

Near Infrared studies during maximum and early decline of Nova Cephei 2014 and Nova Scorpii 2015