Rapidly evolving transients in the Dark Energy Survey
Rapidly evolving transients in the Dark Energy Survey
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DOI：
10.1093/mnras/sty2309
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发表时间：
2018-03
影响因子：
4.8
通讯作者：
M. Pursiainen;M. Childress;M. Smith;S. Prajs;M. Sullivan;T. Davis;R. Foley;J. Asorey;J. Asor
中科院分区：
文献类型：
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作者：
M. Pursiainen;M. Childress;M. Smith;S. Prajs;M. Sullivan;T. Davis;R. Foley;J. Asorey;J. Asor
我们提出的搜索结果迅速演变的瞬变暗能量调查超新星计划。这些事件具有光变曲线快速演化的特点（在100 ~ 100 d内达到峰值，峰值后100 ~ 300 d内呈指数下降），共发现72个事件，其中37个瞬变事件的光谱红移与宿主星系的光谱特征有关。这37个事件使快速光学瞬变的总数增加了两倍以上。它们的红移范围很广（0.05 M > -22.25）。多波段测光很好地拟合了一个黑体达几个星期后的峰值。这些事件在峰值时似乎是热的（T = 10 000-30 000 K）和大的（R = 10 - 2 × 10 cm），并且通常随着时间的推移而膨胀和冷却，尽管一些事件显示出温度大致恒定的光球消退的证据。峰周围的光谱主要是由一个蓝色的无特征的连续一致的热，光学厚喷出物。我们将我们的事件与先前提出的物理场景进行比较，该场景涉及围绕核心坍缩超新星的光学厚风中的冲击爆发，我们得出结论，目前这种场景的模型可能需要额外的电源来描述指数下降。我们发现，这些瞬态往往有利于恒星形成的宿主星系，这可能是一致的核心崩溃的起源。然而，需要更详细的光变曲线模型来确定它们的物理起源。
We present the results of a search for rapidly evolving transients in the Dark Energy Survey Supernova Programme. These events are characterized by fast light-curve evolution (rise to peak in≲10 d and exponential decline in≲30 d after peak).We discovered 72 events, including 37 transients with a spectroscopic redshift from host galaxy spectral features. The 37 events increase the total number of rapid optical transients by more than a factor of two. They are found at a wide range of redshifts (0.05 M > -22.25). The multiband photometry is well fit by a blackbody up to few weeks after peak. The events appear to be hot (T ≈ 10 000-30 000 K) and large (R ≈ 10 - 2 × 10 cm) at peak, and generally expand and cool in time, though some events show evidence for a receding photosphere with roughly constant temperature. Spectra taken around peak are dominated by a blue featureless continuum consistent with hot, optically thick ejecta. We compare our events with a previously suggested physical scenario involving shock breakout in an optically thick wind surrounding a core-collapse supernova, we conclude that current models for such a scenario might need an additional power source to describe the exponential decline. We find that these transients tend to favour star-forming host galaxies, which could be consistent with a core-collapse origin. However, more detailed modelling of the light curves is necessary to determine their physical origin.