Nebular spectra from Type Ia supernova explosion models compared to JWST observations of SN 2021aefx
Nebular spectra from Type Ia supernova explosion models compared to JWST observations of SN 2021aefx
复制标题
Ia 型超新星爆炸模型的星云光谱与 JWST 观测到的 SN 2021aefx 的比较
DOI：
10.1051/0004-6361/202347147
复制
发表时间：
2023
影响因子：
6.5
通讯作者：
Blondin S
中科院分区：
文献类型：
--
作者：
Blondin S
最近JWST对Ia型超新星（SN Ia）2021 aefx星云阶段的观测为后期研究铺平了道路，涵盖了整个光学到中红外（MIR）波长范围，并希望更好地限制SN Ia爆炸机制。（1000-质量，或MCh，延迟爆轰，脉动辅助重力约束爆轰，亚MCh双爆轰，和暴力合并）可以复制完整的光学-MIR光谱SN 2021 aefx在270天后explosion.MethodsWe认为球平均3D模型可从海德堡超新星模型档案，a ~（56）Ni产率在0.5-0.8M·cm ~（-1）范围内。利用辐射传输程序CMFGEN对SN 2021 aefx进行了一维稳态非定域热力学平衡模拟，并将模拟结果与SN 2021 aefx进行了比较。然而，没有一个单一的模型或机制，出现作为一个首选的匹配，和预测的光谱是相似的，尽管非常不同的爆炸机制。我们讨论了可能的原因不匹配的模型，包括喷出物的不对称性和电离效应。我们对Ni III碰撞强度的新计算对7.35 μm和11.00 μm处的两条突出谱线产生了重大影响，并强调需要更准确的禁戒跃迁碰撞数据。使用更新的原子数据，我们确定了一个强大的功能，由于[Ca IV] 3.21 μm，归因于[Ni I]在以前的研究。我们还提供了一个由于[Ne II] 12.81 μm的禁线的初步鉴定，其峰值轮廓表明氖的存在一直到喷出物的最内部区域，例如在暴力合并模型中预测。与以前的说法相反，我们表明，[Ar III] 8.99 μm线可以更广泛的亚MCh模型相比，近MCh模型。最后，总光度线的镍被发现与稳定的镍产量强烈相关，虽然电离效应可以偏置推断的abundance.ConclusionsOur模型表明，关键的物理成分是失踪的爆炸模型，或辐射转移后处理，或两者兼而有之。尽管如此，他们也显示了近红外和和平号的潜力，以发现新的光谱诊断的超新星Ia爆炸机制。
ContextRecent JWST observations of the Type Ia supernova (SN Ia) 2021aefx in the nebular phase have paved the way for late-time studies covering the full optical to mid-infrared (MIR) wavelength range, and with it the hope to better constrain SN Ia explosion mechanisms.AimsWe investigate whether public SN Ia models covering a broad range of progenitor scenarios and explosion mechanisms (Chandrasekhar-mass, orMCh, delayed detonations, pulsationally assisted gravitationally confined detonations, sub-MChdouble detonations, and violent mergers) can reproduce the full optical-MIR spectrum of SN 2021aefx at ∼270 days post explosion.MethodsWe consider spherically averaged 3D models available from the Heidelberg Supernova Model Archive with a56Ni yield in the range 0.5–0.8M⊙. We performed 1D steady-state non-local thermodynamic equilibrium simulations with the radiative-transfer code CMFGEN, and compared the predicted spectra to SN 2021aefx.ResultsThe models can explain the main features of SN 2021aefx over the full wavelength range. However, no single model, or mechanism, emerges as a preferred match, and the predicted spectra are similar to each other despite the very different explosion mechanisms. We discuss possible causes for the mismatch of the models, including ejecta asymmetries and ionisation effects. Our new calculations of the collisional strengths for Ni III have a major impact on the two prominent lines at 7.35 μm and 11.00 μm, and highlight the need for more accurate collisional data for forbidden transitions. Using updated atomic data, we identify a strong feature due to [Ca IV] 3.21 μm, attributed to [Ni I] in previous studies. We also provide a tentative identification of a forbidden line due to [Ne II] 12.81 μm, whose peaked profile indicates the presence of neon all the way to the innermost region of the ejecta, as predicted for instance in violent merger models. Contrary to previous claims, we show that the [Ar III] 8.99 μm line can be broader in sub-MChmodels compared to near-MChmodels. Last, the total luminosity in lines of Ni is found to correlate strongly with the stable nickel yield, although ionisation effects can bias the inferred abundance.ConclusionsOur models suggest that key physical ingredients are missing from either the explosion models, or the radiative-transfer post-processing, or both. Nonetheless, they also show the potential of the near- and MIR to uncover new spectroscopic diagnostics of SN Ia explosion mechanisms.