1. Broad-lined type Ic supernova iPTF16asu: A challenge to all popular models
- Author
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Ministry of Science and Technology of the People's Republic of China, National Natural Science Foundation of China, University of California, Berkeley, University of Nevada, Las Vegas, Wang, L. J., Wang, X. F., Cano, Z., Wang, S. Q., Liu, L.D., Dai, Z. G., Deng, J. S., Yu, H., Li, B., Song, L. M., Qiu, Y. L., Wei, J. Y., Ministry of Science and Technology of the People's Republic of China, National Natural Science Foundation of China, University of California, Berkeley, University of Nevada, Las Vegas, Wang, L. J., Wang, X. F., Cano, Z., Wang, S. Q., Liu, L.D., Dai, Z. G., Deng, J. S., Yu, H., Li, B., Song, L. M., Qiu, Y. L., and Wei, J. Y.
- Abstract
It is well known that ordinary supernovae (SNe) are powered by 56Ni cascade decay. Broad-lined type Ic SNe (SNe Ic-BL) are a subclass of SNe that are not all exclusively powered by 56Ni decay. It was suggested that some SNe Ic-BL are powered by magnetar spin-down. iPTF16asu is a peculiar broad-lined type Ic supernova discovered by the intermediate Palomar Transient Factory. With a rest-frame rise time of only 4 d, iPTF16asu challenges the existing popular models, for example, the radioactive heating (56Ni-only) and the magnetar +56Ni models. Here we show that this rapid rise could be attributed to interaction between the SN ejecta and a pre-existing circumstellar medium ejected by the progenitor during its final stages of evolution, while the late-time light curve can be better explained by energy input from a rapidly spinning magnetar. This model is a natural extension to the previous magnetar model. The mass-loss rate of the progenitor and ejecta mass are consistent with a progenitor that experienced a common envelope evolution in a binary. An alternative model for the early rapid rise of the light curve is the cooling of a shock propagating into an extended envelope of the progenitor. It is difficult at this stage to tell which model (interaction+magnetar + 56Ni or cooling+magnetar + 56Ni) is better for iPTF16asu. However, it is worth noting that the inferred envelope mass in the cooling+magnetar + 56Ni is very high.© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
- Published
- 2019