Cahill Centre for Astrophysics, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA.
Department of Particle Physics and Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100, Israel.
Science. 2018 Oct 12;362(6411):201-206. doi: 10.1126/science.aas8693.
Compact neutron star binary systems are produced from binary massive stars through stellar evolution involving up to two supernova explosions. The final stages in the formation of these systems have not been directly observed. We report the discovery of iPTF 14gqr (SN 2014ft), a type Ic supernova with a fast-evolving light curve indicating an extremely low ejecta mass (≈0.2 solar masses) and low kinetic energy (≈2 × 10 ergs). Early photometry and spectroscopy reveal evidence of shock cooling of an extended helium-rich envelope, likely ejected in an intense pre-explosion mass-loss episode of the progenitor. Taken together, we interpret iPTF 14gqr as evidence for ultra-stripped supernovae that form neutron stars in compact binary systems.
紧凑的中子星双星系统是通过涉及多达两次超新星爆炸的双星演化产生的。这些系统形成的最后阶段尚未被直接观测到。我们报告了 iPTF14gqr（SN2014ft）的发现，这是一颗 Ic 型超新星，其光曲线的快速演化表明其抛射物质的质量极低（≈0.2 个太阳质量），动能也极低（≈2×10 ergs）。早期的光度和光谱学研究揭示了膨胀氦丰富包层的激波冷却的证据，这可能是在前身星剧烈的爆发前质量损失事件中抛出的。综上所述，我们将 iPTF14gqr 解释为形成紧凑双星系统中中子星的超贫超新星的证据。
