The synchronized dance of the magellanic clouds’ star formation history
The synchronized dance of the magellanic clouds’ star formation history
复制标题
麦哲伦星云的同步舞蹈——恒星形成历史
DOI：
10.1093/mnrasl/slac030
复制
发表时间：
2022
影响因子：
--
通讯作者：
Monelli, M
中科院分区：
文献类型：
--
作者：
Massana, P;Ruiz-Lara, T;Noël, N E;Gallart, C;Nidever, D L;Choi, Y;Sakowska, J D;Besla, G;Olsen, K A;Monelli, M
我们使用的SMASH调查，以获得前所未有的深测光达到最古老的主序关闭的颜色星等图（CMD）的小麦哲伦云（SMC）和定量推导其星星形成历史（SFH）使用CMD拟合技术。我们确定了最后3.5 Gyr中星星形成的五个独特的峰，分别在10.3 Gyr，10.2 Gyr，10.1 Gyr，10.45 Gyr前，还有一个现在。我们将这些与大麦哲伦星云（LMC）的SFH进行比较，发现明确的同步性，两个星系在过去的3.5 Gyr中显示出类似的增强星星形成时期。它们的SFH之间的平行性表明，MC之间的潮汐相互作用至少在过去的10.35 Gyr，潮汐截断SMC和塑造LMC的螺旋臂反复发挥了重要作用。我们首次显示，SMC-LMC相关SFH在最近的时间，其中星星形成的增强局部化在LMC的北方螺旋臂，在全球范围内的SMC。这些新的发现不仅可以用来限制MC的轨道历史，还可以用来限制在模拟中如何处理星星的形成。
We use the SMASH survey to obtain unprecedented deep photometry reaching down to the oldest main-sequence turn-offs in the colour–magnitude diagrams (CMDs) of the Small Magellanic Cloud (SMC) and quantitatively derive its star formation history (SFH) using CMD fitting techniques. We identify five distinctive peaks of star formation in the last 3.5 Gyr, at ∼3, ∼2, ∼1.1, ∼0.45 Gyr ago, and one presently. We compare these to the SFH of the Large Magellanic Cloud (LMC), finding unequivocal synchronicity, with both galaxies displaying similar periods of enhanced star formation over the past ∼3.5 Gyr. The parallelism between their SFHs indicates that tidal interactions between the MCs have recurrently played an important role in their evolution for at least the last ∼3.5 Gyr, tidally truncating the SMC and shaping the LMC’s spiral arm. We show, for the first time, an SMC–LMC correlated SFH at recent times in which enhancements of star formation are localized in the northern spiral arm of the LMC, and globally across the SMC. These novel findings should be used to constrain not only the orbital history of the MCs but also how star formation should be treated in simulations.