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Radioactivity of the Key Isotope 44Ti in SN 1987A

Yuko Motizuki·Shiomi Kumagai
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Abstract

We investigate radioactivity from the decay sequence of 44Ti in a young supernova remnant SN 1987A. We perform Monte-Carlo simulations of degradation of the nuclear lines to explain a late-time bolometric luminosity which is estimated from optical and near-infrared observation at 3600 days after the explosion. Assuming the distance to LMC in between 45.5 and 52.1 kpc, we have obtained the initial 44Ti mass of (0.82-2.3) 10^{-4} solar mass within the current uncertainty of the physical quantities. The resulting fluxes of gamma- and hard X-rays emerged from the 44Ti decay are estimated and compared with the line sensitivity of the INTEGRAL/SPI on board and that of NeXT X-ray satellite planned to be launched in 2010. The effect of 44Ti ionization on the estimated fluxes is briefly remarked.

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Yuko Motizuki, Shiomi Kumagai. 2003-12-25. Radioactivity of the Key Isotope 44Ti in SN 1987A. https://doi.org/10.1063/1.1737130

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