Duerbeck, H. W. ; Sterken, C. ; Baptista, R. ; Cunha, K. ; Diaz, M. P. ; Dutra, C. M. ; Freyhammer, L. ; Hensberge, H. ; Jones, A. F.

published in Interplay of Periodic, Cyclic and Stochastic Variability in Selected Areas of the H-R Diagram, 292, pp. 309 (2003)

Abstract: The outburst of the recurrent nova IM Nor was followed photometrically and spectroscopically. In the beginning of the outburst, the spectrum of the nova belonged to the Fe II class, but after one month, it changed to the He/N class. Thus IM Nor is one of the hybrid novae, and has many spectroscopic similarities with CI Aql and T Pyx, the other two known slow recurrent novae. The strengths of the interstellar Ca II, Na I, and K I lines and of the diffuse interstellar bands indicate an interstellar extinction E(B-V) > 0.8 and a distance d > 2.5 kpc. The absolute magnitude of IM Nor is comparable to that of classical novae of the same speed class.

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