Optical and infrared photometry of the Type IIn SN 1998S: days 11-146

• DOI: 10.1046/j.1365-8711.2000.03797.x
• Publication Date: 2003-03-12T13:19:53Z
• Authors: A. Fassia; W. P. S. Meikle; W. D. Vacca; S. N. Kemp; N. A. Walton; D. L. Pollacco; S. Smartt; A. Oscoz; A. Aragon-Salamanca; S. Bennett; T. G. Hawarden; A. Alonso; D. Alcalde; A. Pedrosa; J. Telting; M. J. Arevalo; H. J. Deeg; F. Garzon; A. Gomez-Roldan; G. Gomez; C. Gutierrez; S. Lopez; M. Rozas; M. Serra-Ricart; M. R. Zapatero-Os...
• Keywords: Circumstellar dust; Infrared excess

We present contemporaneous optical and infrared (IR) photometric observations of the Type IIn SN 1998S covering period between 11 146 d after discovery. The IR data constitute first ever light curves a supernova. use blackbody spline fits to photometry examine luminosity evolution. During 2–3 months, is dominated by release shock-deposited energy in ejecta. After ∼100 powered mostly deposition radioactive decay from 0.15±0.05 M⊙ 56Ni which was produced explosion. also report discovery an astonishingly high excess, K−L′=2.5, that at day 130. interpret this as being due thermal emission dust grains vicinity argue produce such so soon explosion, must be pre-existing located circumstellar medium progenitor. could heated either UV/optical flash (IR echo) or X-rays interaction ejecta with material.