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Freeze-out Effects in Hydrogen and Helium Lines of SN 1987A at the Early Photospheric Epoch

V. P. Utrobin·N. N. Chugai
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Abstract

We have developed a time-dependent model of ionization, excitation and energy balance of SN 1987A atmosphere at the photospheric epoch to study early behavior of hydrogen and helium lines. The ionization freeze-out effects play a key role in producing both the strong H-alpha during nearly the first month and the He I 5876 A scattering line on day 1.76. Using an extended reaction network between hydrogen molecules and their ions demonstrates that ion-molecular processes are likely responsible for the blue peak in H-alpha profile at the Bochum event epoch.

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V. P. Utrobin, N. N. Chugai. 2002-09-18. Freeze-out Effects in Hydrogen and Helium Lines of SN 1987A at the Early Photospheric Epoch. https://doi.org/10.1007/10828549_34

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