Impact of Magnetar Power on Stripped-Envelope Supernovae Over Time
Recent research has focused on the long-term effects of magnetar power in stripped-envelope supernovae, specifically examining how this power influences observable characteristics of these cosmic events over time. The study, titled "The long-term influence of a magnetar power in stripped-envelope supernovae. Radiative-transfer modeling of He-star explosions from 1 to 10 years," was conducted by Luc Dessart and submitted to arXiv on August 25, 2024.
The research utilizes a comprehensive grid of one-dimensional nonlocal thermodynamic equilibrium radiative transfer calculations to analyze helium star explosions influenced by magnetar power from one to ten years post-explosion. The findings indicate that the observable properties of supernovae vary significantly based on factors such as the mass of the helium star, the age of the supernova, the amount of power injected, and the degree of ejecta clumping.
Key results show that for high-mass helium stars, the primary coolants in the ejecta are oxygen (O) and neon (Ne), with specific emission lines dominating in the optical spectrum. In contrast, lower-mass helium stars exhibit a wider variety of coolants, including iron (Fe), sulfur (S), argon (Ar), and nickel (Ni). The study also notes that ionization levels in the ejecta increase over time, with doubly ionized species becoming more prevalent around the ten-year mark, although this ionization can be significantly reduced by the presence of clumping.
The research highlights that the magnetar-powered model aligns well with observations of Type Ib supernova SN2012au, particularly at various stages post-explosion. The findings suggest that massive magnetar-powered ejecta should be notably luminous in the infrared spectrum between five to ten years after the explosion, primarily due to strong emission from the [NeII] 12.81 micron line.
This study contributes to the understanding of supernova mechanics and the role of magnetars, potentially aiding in the interpretation of future astronomical observations. The full paper can be accessed at arXiv:2408.13844.