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arXiv · 2006.09810

Optical studies of two stripped envelope supernovae SN 2015ap (Type Ib) and SN 2016P (Type Ic)

Anjasha Gangopadhyay·Kuntal Misra·D. K. Sahu·Shan-Qin Wang·Brajesh Kumar·Long Li·G. C. Anupama·Raya Dastidar·N. Elias-Rosa·Brijesh Kumar·Mridweeka Singh·S. B. Pandey·Pankaj Sanwal·Avinash Singh·S. Srivastav·L. Tartaglia·L. Tomasella
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Abstract

We present the photometric and spectroscopic studies of a Type Ib SN 2015ap and a Type Ic SN 2016P. SN 2015ap is one of the bright (M$_{V}$ = $-$18.04 mag) Type Ib while SN 2016P lies at an average value among the Type Ic SNe (M$_{V}$ = $-$17.53 mag). Bolometric light curve modelling of SNe 2015ap and 2016P indicates that both the SNe are powered by $^{56}$Ni + magnetar model with $^{56}$Ni masses of 0.01 M$_{\odot}$ and 0.002 M$_{\odot}$, ejecta masses of 3.75 M$_{\odot}$ and 4.66 M$_{\odot}$, spin period P$_{0}$ of 25.8 ms and 36.5 ms and magnetic field B$_{p}$ of 28.39 $\times$ 10$^{14}$ Gauss and 35.3 $\times$ 10$^{14}$ Gauss respectively. The early spectra of SN 2015ap shows prominent lines of He with a "W" feature due to Fe complexes while other lines of Mg II, Na I and Si II are present in both SNe 2015ap and 2016P. Nebular phase [O I] profile indicates an asymmetric profile in SN 2015ap. The [O I]/[Ca II] ratio and nebular spectral modelling of SN 2015ap hints towards a progenitor mass between 12 $-$ 20 M$_{\odot}$.

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Anjasha Gangopadhyay, Kuntal Misra, D. K. Sahu, Shan-Qin Wang, Brajesh Kumar, Long Li, G. C. Anupama, Raya Dastidar, N. Elias-Rosa, Brijesh Kumar, Mridweeka Singh, S. B. Pandey, Pankaj Sanwal, Avinash Singh, S. Srivastav, L. Tartaglia, L. Tomasella. 2020-06-19. Optical studies of two stripped envelope supernovae SN 2015ap (Type Ib) and SN 2016P (Type Ic). https://doi.org/10.1093/mnras%2Fstaa1821

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