ISO/SWS observations of SN 1987A

Abstract

Ti. Assessing various uncertainties of the model, and checking the late optical emission it predicts, we obtain an upper limit of 1.1 × 10 −4 M . This is lower than in our previous estimate using other ISO data, and we compare our new result with other models for the late emission, as well as with expected yields from explosion models. We also show that steady-state models for the optical emission are likely to overestimate the mass of ejected 44 Ti. The low limit we find for the mass of ejected 44 Ti could be higher if dust cooling is important. A direct check on this is provided by the gamma-ray emission at 1.157 Mev as a result of the radioactive decay of 44 Ti.

Radioactivities and nucleosynthesis in SN 1987A

“…This method also yields the best estimate of the 57 Ni mass, ∼ 3.3 × 10 −3 M ⊙ . A more complete discussion of these results will be given in Fransson & Kozma (2001).…”

“…A severe problem is, however, that modeling of individual lines is very sensitive to atomic data, which in spite of dramatic improvements from the IRON-project, is still a problem. In a similar attempt Lundqvist et al (2001) have tried to use the FIR [Fe II] 26.0µ fine structure line in connection with observations by ISO. Unfortunately, only an upper limit to the flux was obtained, yielding an upper limit to the 44 Ti mass of 1.1 ×10 −4 M ⊙ .…”

Optical and infrared observations of radioactive elements in supernovae

“…This line was observable by the Infrared Space Observatory (ISO) which was therefore pointed toward SN 1987A. However, no emission from the supernova was detected (Lundqvist, Sollerman, Kozma et al 1999).…”

Gamma-ray signatures of supernovae and hypernovae

“…Note that Chugai et al [52] estimated that positrons from (1-2) × 10 −4 M of 44 Ti provides the overall luminosity of the FeII emission lines, and Lundqvist et al [53,54] obtained the upper limit of the 44 Ti mass, 1 -1.5 ×10 −4 M , based on ISO SWS/LWS observations. 44 …”