论文标题
Meerkat Galaxy群集传统调查：巨大簇中的星形形成为0.15 <z <0.35
The MeerKAT Galaxy Clusters Legacy Survey: star formation in massive clusters at 0.15 < z < 0.35
论文作者
论文摘要
我们研究了20个大型聚类（$ M_ {200}> 4 \ times10^{14} {\ rm M} _ {\ rm m} _ {\ odot} $在$ 0.15 <z <z <0.35 $之间，使用$ lmme Meer（$ rm Me） Galaxy群集传统调查目录。我们使用来自Dark Energy Camera Legacy调查的光学数据来估计照片-Y $ Z $ S并分配集群会员资格。我们观察到星形星系的分数（$ f _ {\ rm sf} $）从$ 2R_ {200} $到我们完整的聚类样本中的群集中心的分数（$ f _ {\ rm sf} $），但注意到$ f _ {\ rm sf} $在$ f _ {\ rm sf} $之间存在显着差异。非拉迪奥/遗物托管簇。对于$ r_ {200} $中的星形星系，簇中的$ f _ {\ rm sf} $托管无线电光环和遗物（$ 0.148 \ pm0.016 $）为$ \ ofd23 \％$ $ \ oft yout23 \％$ $ $比非radio-halo/relic astring tosting clusters clusters（$ 0.1111 $ pm）（$ 0.1111）。我们观察到$3σ$的差额在非拉迪奥 - 哈洛/遗物托管群集（$ 21.5 \ pm1.9 $ m $ _ {\ odot} $ yr $^{ - 1} $/$ 10^{14} $ 10^{14} $ m $ _ {\ odot} $中，clusist and for Clusists和clusesters和clusesters的总质量差异（$ 21.5 \ pm1.9 $ _ {\ odot} $ 21.5 \ pm1.9 $ _ {\ odot} $ _ {\ odot} （$ 26.1 \ pm1.4 $ m $ _ {\ odot} $ yr $^{ - 1} $/$ 10^{14} $ M $ _ {\ odot} $）。在我们的红移切片处的SFR高于发光的红外星系（LIRGS）SFR的星系群的质量标准化群集群的总体SFR下降了$ \ of4 \ times $下降，对应于2 gyr，在外观的时间为2 gyr。这与SF活性的迅速下降是一致的，并且在先前的研究使用红外衍生的SFR的研究中，红移降低了。
We investigate dust-unbiased star formation rates (SFR) as a function of the environment in 20 massive clusters ($M_{200}>4\times10^{14} {\rm M}_{\odot}$) between $0.15<z<0.35$ using radio luminosities ($L_{\rm 1.4GHz}$) from the recently released MeerKAT Galaxy Cluster Legacy Survey catalogue. We use optical data from the Dark Energy Camera Legacy Survey to estimate photo-$z$s and assign cluster membership. We observe a steady decline in the fraction ($f_{\rm SF}$) of star-forming galaxies from $2R_{200}$ to the cluster centres in our full cluster sample, but notice a significant difference in $f_{\rm SF}$ gradients between clusters hosting large-scale extended radio emission in the form of haloes and relics (associated with ongoing merger activity) and non-radio-halo/relic hosting clusters. For star-forming galaxies within $R_{200}$, the $f_{\rm SF}$ in clusters hosting radio haloes and relics ($0.148\pm0.016$) is $\approx23\%$ higher than in non-radio-halo/relic hosting clusters ($0.120\pm0.011$). We observe a $3σ$ difference between the total SFR normalised by cluster mass for non-radio-halo/relic hosting clusters ($21.5\pm1.9$ M$_{\odot}$yr$^{-1}$/$10^{14}$M$_{\odot}$) and for clusters with radio haloes and relics ($26.1\pm1.4$ M$_{\odot}$yr$^{-1}$/$10^{14}$M$_{\odot}$). There is a $\approx4\times$ decline in the mass normalised total SFR of clusters for galaxies with SFR above the luminous infrared galaxies (LIRGs) SFR limit at our redshift slice, corresponding to 2 Gyr in look-back time. This is consistent with the rapid decline in SF activity with decreasing redshift amongst cluster LIRGs seen by previous studies using infrared-derived SFR.
