标题： Ia型超新星SN 2014dt的中红外发射过量现象 显示英文标题

标题： An Excess of Mid-Infrared Emission from the Type Iax SN 2014dt

摘要： I型超新星（SNe Iax）的能量和亮度都低于典型的热核爆炸。 对于这一子类的观测特性，一个可能的解释是由一颗吸积氦星伴星的碳氧白矮星主星组成的双星前身系统。 预期单简并爆炸通道会形成密集的星周介质（CSM），尽管尚未观察到这种子类存在这样的CSM的证据。 在这里，我们展示了通过SPIRITS项目获得的SN Iax 2014dt的近期斯皮策太空望远镜观测结果，这些观测是在爆炸后近一年进行的，揭示了比更正常的SNe Ia预期通量强得多的中红外过量辐射。 这个过量与1E-5 M_solar的新尘埃形成一致，这将是首次观察到正常Ia型超新星中新尘埃的形成。 然而，这个过量也与可能在爆炸前质量损失中形成的尘埃CSM一致，从而暗示了一个单简并前身系统。 与其他显示出显著冲击相互作用的SNe Ia（SNe Ia-CSM）和相互作用的核心坍缩事件（SNe IIn）相比，SN 2014dt中的尘埃壳质量较小。 我们考虑了这样一个预存尘埃壳对前身系统的影响，包括一个具有质量供体的双星系统，该供体是一颗红巨星、红超巨星和渐近巨星分支星。 显示英文摘要

摘要： Supernovae Type Iax (SNe Iax) are less energetic and less luminous than typical thermonuclear explosions. A suggested explanation for the observed characteristics of this subclass is a binary progenitor system consisting of a CO white dwarf primary accreting from a helium star companion. A single-degenerate explosion channel might be expected to result in a dense circumstellar medium (CSM), although no evidence for such a CSM has yet been observed for this subclass. Here we present recent Spitzer observations of the SN Iax 2014dt obtained by the SPIRITS program nearly one year post-explosion that reveal a strong mid-IR excess over the expected fluxes of more normal SNe Ia. This excess is consistent with 1E-5 M_solar of newly formed dust, which would be the first time that newly formed dust has been observed to form in a normal Type Ia. The excess, however, is also consistent with a dusty CSM that was likely formed in pre-explosion mass-loss, thereby suggesting a single degenerate progenitor system. Compared to other SNe Ia that show significant shock interaction (SNe Ia-CSM) and interacting core-collapse events (SNe IIn), this dust shell in SN 2014dt is less massive. We consider the implications that such a pre-existing dust shell has for the progenitor system, including a binary system with a mass donor that is a red giant, a red supergiant, and an asymptotic giant branch star.