Discovery of a red backsplash galaxy candidate near M81
Discovery of a red backsplash galaxy candidate near M81
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在 M81 附近发现红色后溅星系候选者
DOI：
10.1093/mnras/stad352
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发表时间：
2023
影响因子：
4.8
通讯作者：
Davis, A. Bianca
中科院分区：
文献类型：
--
作者：
Casey, Kirsten J.;Greco, Johnny P.;Peter, Annika H. G.;Davis, A. Bianca
了解低质量星系中的猝灭机制对于全面了解星系演化是至关重要的。特别是，孤立的星系是帮助解开影响恒星形成的复杂内部和外部过程的重要工具。低质量区淬火星系和卫星星系之间的比较为发现提供了一个实质性的机会，尽管很少有质量在任何宿主晕的维里半径Rvir之外的猝灭星系。重要的是，模拟和观测表明，还存在一个介于两者之间的背溅射星系群，这可能是对环境猝灭的解释的补充。背溅射星系--类似于场星系--位于主晕的维里半径之外，但它们的恒星形成可能会受到之前与更大质量系统的相互作用的深刻影响。在这篇文章中，我们同时发现了一个来自M81群的低质量()猝灭星系，大约是1Rvirin投影。我们使用表面亮度起伏(SBF)来研究新星系Dw0910+7326(绰号Blobby)是背溅射星系或更远的场星系的可能性。测得的$3.21\SUBSTACK{+0.15+0.15-0.36}$MPC的SBF距离表明，Blobby可能在组合的M81-M82系统之外的1.0<；R/Rvir<；2.7范围内。考虑到它的距离和宁静，Blobby是一个很好的后溅星系候选者，并可能为这些有趣天体的形成和演化提供线索。
Understanding quenching mechanisms in low-mass galaxies is essential for understanding galaxy evolution overall. In particular, isolated galaxies are important tools to help disentangle the complex internal and external processes that impact star formation. Comparisons between quenched field and satellite galaxies in the low-mass regime offer a substantial opportunity for discovery, although very few quenched galaxies with masses beloware known outside the virial radius,Rvir, of any host halo. Importantly, simulations and observations suggest that an in-between population of backsplash galaxies also exists that may complement interpretations of environmental quenching. Backsplash galaxies – like field galaxies – reside outside the virial radius of a host halo, but their star formation can be deeply impacted by previous interactions with more massive systems. In this paper, we report the concurrent discovery of a low-mass () quenched galaxy approximately 1Rvirin projection from the M81 group. We use surface brightness fluctuations (SBF) to investigate the possibility that the new galaxy, dw0910+7326 (nicknamed Blobby), is a backsplash galaxy or a more distant field galaxy. The measured SBF distance of $3.21\substack{+0.15 +0.41 \\-0.15 -0.36}$ Mpc indicates that Blobby likely lies in the range 1.0 <R/Rvir< 2.7 outside the combined M81–M82 system. Given its distance and quiescence, Blobby is a good candidate for a backsplash galaxy and could provide hints about the formation and evolution of these interesting objects.