2008MNRAS.387..344M

The moderately fast Nova Oph 2007 reached maximum brightness on 2007 March 28 at V = 8.52, B - V = +1.12, V - R_C = +0.76, V - I_C= +1.59 and R_C- I_C= +0.83, after fast initial rise and a pre-maximum halt lasting a week. Decline times were t^V₂= 26.5, t^B₂= 30, t^V₃ = 48.5 and t^B₃= 56.5 d. The distance to the nova is d = 3.7±0.2 kpc, the height above the Galactic plane is z = 215 pc, the reddening is E(B - V) = 0.90 and the absolute magnitude at maximum is M^max_V= -7.2 and M^max_B= -7.0. The spectrum four days before maximum resembled a F6 supergiant, in an agreement with broad-band colours. It later developed into that of a standard `FeII'-class nova. Nine days past maximum, the expansion velocity estimated from the width of Hα emission component was ∼730 km/s, and the displacement from it of the principal and diffuse-enhanced absorption systems was ∼650 and 1380 km/s, respectively. Dust probably formed and disappeared during the period from 82 to 100 d past maximum, causing (at peak dust concentration) an extinction of ΔB = 1.8 mag and an extra ΔE(B - V) = 0.44 reddening.