| Name: Aditya Pandey |
| Affiliation: Indian Institute of Technology (Indian School of Mines) Dhanbad |
| Conference ID: ASI2026_662 |
| Title: Probing Type Ia Supernovae Using Double-Detonation Models |
| Abstract Type: Poster |
| Abstract Category: High Energy Phenomena, Fundamental Physics and Astronomy |
| Author(s) and Co-Author(s) with Affiliation: Aditya Pandey(Indian Institute of Technology (Indian School of Mines) Dhanbad, Dhanbad - 826004, India), Esha Kundu(Indian Institute of Technology (Indian School of Mines) Dhanbad, Dhanbad - 826004, India) |
| Abstract: The progenitors of Type Ia supernovae and the nature of their explosion mechanism remain among the major open problems in thermonuclear runaways. One important pathway to explain the observed diversity of Type Ia events is the double-detonation scenario, in which a surface helium detonation triggers a secondary detonation in an underlying carbon–oxygen white dwarf core. A characteristic and widely discussed observational signature of this scenario is the presence of high-velocity calcium absorption features. In this work, we have computed synthetic spectra for a double-detonation model using a one-dimensional radiative-transfer code, along with density and abundance structures derived from hydrodynamical simulations of sub-Chandrasekhar-mass C/O white dwarfs available in the literature. While the origin of high-velocity calcium absorption remains unclear, the double-detonation scenario provides a natural framework for producing calcium in the outer ejecta at very high velocities. Observationally, several supernovae, including SN 2019eix, exhibit prominent calcium absorption features consistent with expectations from double-detonation models. We directly compare our synthetic spectra with observations of recent Type Ia explosions, whose spectra display strong calcium absorption around 8000 angstroms, and, therefore, can be possible candidates for the double detonation scenarios. However, further multi-epoch spectroscopic analysis, combined with light-curve modeling, is required to robustly assess whether these events can be classified as definitive double-detonation candidates. |
