SIMBAD references

High resolution spectra of SN 1993J obtained on March 31.0, only three days past outburst, show narrow emission lines due to Hα, HeII λ4686 and to the high ionization [FeX]λ6374 and [FeXIV]λ5303. The latter, to our knowledge, has never been identified before in SN spectra. The FWHM of the recombination lines indicates that the emitting gas has velocities ∼170km/s which seems too large to be attributed to a normal stellar wind. The detection of narrow lines soon after outburst and their disappearance one week later, indicate that the circumstellar gas is confined close to the exploding star (R≤4x10¹⁵cm). The coronal lines are probably generated in the CSM heated by the radiation emerging from the shocked regions. A kinetic temperature of ∼2.5x10⁶K is derived from the line widths. The interstellar NaID absorption shows a multiple component structure in agreement with previous reports. Its equivalent width suggests a moderately high reddening, 0.2≤E(B-V)=<0.8 wheras the upper limits to the 5780A and 5797A DIBs indicates a reddening E(B-V)=<0.4