论文标题
主要序列散射是真实的：星系聚类对恒星形成和恒星质量的关节依赖性
Main Sequence Scatter is Real: The Joint Dependence of Galaxy Clustering on Star Formation and Stellar Mass
论文作者
论文摘要
我们介绍了$ \ sim40,000 $ SDSS星系$ z \ sim0.03 $的恒星质量完整样品聚类的新测量结果，作为恒星质量和特定的星形形成率（SSFR）的联合功能。我们的结果证实了Coil等。 （2017年）以$ z \ sim0.7 $：Galaxy聚类在固定恒星质量下比固定SSFR处的恒星质量更强的功能。我们还发现，在给定的恒星质量下，具有较高SSFR的星形主序列（SFM）上方的星系比SSFR下方的星系群较低。静态星系也存在类似的趋势。这证实主序列散射和静态序列内的散射在物理上连接到大尺度宇宙密度场。对于$ {0 <z <1.2} $的不同星系样品与基于基于Behroozi等人的经验星系进化模型的模拟星系目录的不同星系样品，我们将所得的星系偏差与SSFR与SSFR相比与SSFR比进行了比较。 （2019）。该模型在中间红移中符合Primus和Deep2聚类数据，但与SDSS的一致性并不那么强。我们表明，在模型中以$ z \ sim0 $为$ z \ sim0 $增加了Galaxy SFR和Halo积聚率之间的相关性，从而大大改善了与SDSS数据的一致性。模拟目录表明，中央星系在给定的恒星质量下对SSFR的聚类的依赖性做出了重大贡献，并且信号不仅仅是卫星星系分数与SSFR的影响。我们的结果对星系演化模型高度限制，并表明恒星至局部质量关系（SHMR）取决于SSFR。
We present new measurements of the clustering of stellar mass-complete samples of $\sim40,000$ SDSS galaxies at $z\sim0.03$ as a joint function of stellar mass and specific star formation rate (sSFR). Our results confirm what Coil et al. (2017) find at $z\sim0.7$: galaxy clustering is a stronger function of sSFR at fixed stellar mass than of stellar mass at fixed sSFR. We also find that galaxies above the star-forming main sequence (SFMS) with higher sSFR are less clustered than galaxies below the SFMS with lower sSFR, at a given stellar mass. A similar trend is present for quiescent galaxies. This confirms that main sequence scatter, and scatter within the quiescent sequence, is physically connected to the large-scale cosmic density field. We compare the resulting galaxy bias versus sSFR, and relative bias versus sSFR ratio, for different galaxy samples across ${0<z<1.2}$ to mock galaxy catalogs based on the empirical galaxy evolution model of Behroozi et al. (2019). This model fits PRIMUS and DEEP2 clustering data well at intermediate redshift, but agreement with SDSS is not as strong. We show that increasing the correlation between galaxy SFR and halo accretion rate at $z\sim0$ in the model substantially improves agreement with SDSS data. Mock catalogs suggest that central galaxies contribute substantially to the dependence of clustering on sSFR at a given stellar mass and that the signal is not simply an effect of satellite galaxy fraction differences with sSFR. Our results are highly constraining for galaxy evolution models and show that the stellar-to-halo mass relation (SHMR) depends on sSFR.
