SN 1998S was a Type IIn supernova that was detected in NGC 3877 in March 1998. At the time of discovery, SN 1998S was the brightest Type IIn event observed,[1] although later outshone by SN 2010jl.[2]

It was discovered on 1998 March 2.68 UT in NGC 3877 by Z. Wan at a broadband (unfiltered) optical magnitude of +15.2.

Its spectrum showed prominent H and He emission lines with narrow peaks and broad wings, superimposed on a blue continuum. These narrow lines indicate the presence of a dense circumstellar medium (CSM) in the vicinity of the supernova. The high luminosity of SN1998S is due to the interaction of fast material (ejecta) with previously-expelled slowly-expanding material (CSM), which can more effectively convert kinetic energy of ejecta into radiation energy.[3]

References

  1. ^ Fassia, A.; Meikle, W. P. S.; Chugai, N.; Geballe, T. R.; Lundqvist, P.; Walton, N. A.; Pollacco, D.; Veilleux, S.; Wright, G. S.; Pettini, M.; Kerr, T.; Puchnarewicz, E.; Puxley, P.; Irwin, M.; Packham, C.; Smartt, S. J.; Harmer, D. (11 August 2001). "Optical and infrared spectroscopy of the type IIn SN 1998S: days 3-127". Monthly Notices of the Royal Astronomical Society. 325 (3): 907–930. arXiv:astro-ph/0011340. Bibcode:2001MNRAS.325..907F. doi:10.1046/j.1365-8711.2001.04282.x. S2CID 119514186
  2. ^ Ofek, E. O.; Zoglauer, A.; Boggs, S. E.; Barriere, N. M.; Reynolds, S. P.; Fryer, C. L.; Harrison, F. A.; Cenko, S. B.; Kulkarni, S. R.; Gal-Yam, A.; Arcavi, I.; Bellm, E.; Bloom, J. S.; Christensen, F.; Craig, W. W. (2014-01-06). "SN 2010jl: Optical to hard X-ray observations reveal an explosion embedded in a ten solar mass cocoon". The Astrophysical Journal. 781 (1): 42. arXiv:1307.2247. Bibcode:2014ApJ...781...42O. doi:10.1088/0004-637X/781/1/42. ISSN 0004-637X
  3. ^ Dessart, Luc (2015). "Numerical simulations of super-luminous supernovae of type IIn". MNRAS. 449 (4): 4304–4325. arXiv:1503.05463. Bibcode:2015MNRAS.449.4304D. doi:10.1093/mnras/stv609. S2CID 54221511