We present a study of the dust associated with the core-collapse supernova
SN~1995N. Infrared emission detected 14--15 years after the explosion was
previously attributed to thermally echoing circumstellar material associated
with the SN progenitor. We argue that this late-time emission is unlikely to be
an echo, and is more plausibly explained by newly formed dust in the supernova
ejecta, indirectly heated by the interaction between the ejecta and the CSM.
Further evidence in support of this scenario comes from emission line profiles
in spectra obtained 22 years after the explosion; these are asymmetric, showing
greater attenuation on the red wing, consistent with absorption by dust within
the expanding ejecta. The spectral energy distribution and emission line
profiles at epochs later than ∼5000 days are both consistent with the
presence of about 0.4~M⊙​ of amorphous carbon dust. The onset of dust
formation is apparent in archival optical spectra, taken between 700 and 1700
days after the assumed explosion date. As this is considerably later than most
other instances where the onset of dust formation has been detected, we argue
that the explosion date must be later than previously assumed.Comment: 14 pages, 16 figures. Accepted for publication in Monthly Notices of
the Royal Astronomical Societ