We present flux densities and polarization percentages of 159 radio galaxies based on nearly simultaneous VLA observations at four frequencies from 5 to 43GHz. This sample is selected from the high-frequency Australia Telescope 20GHz (AT20G) survey and consists of all sources with S_{20GHz}>40mJy in an equatorial field of the ACT survey. For a subset of 25 of these sources we used the GBT to obtain 90GHz data. The goals of this program are: 1) a characterization of the spectra, polarization and variability of high frequency-selected radio sources; 2) extrapolating from the few GHz regime to the ~150GHz regime of the ACT survey, allowing for more accurate removal of the radio source signal in our particular field; and 3) providing a data set that will allow more accurate modeling of the high-frequency radio source contamination in current and future SZ and CMB experiments. We find that, as expected, this sample consists of flatter spectrum and more compact or point-like sources than low frequency-selected samples. In the K-band, variability is typically <~20%, although there are exceptions. The higher frequency data is well suited to the detection of extreme Giga-Hertz Peak spectrum Sources (GPS). The inclusion of the 43GHz data causes the relative fraction of inverted spectrum sources to go down and of peaked spectrum sources to go up when compared with the AT20G survey results. The trend largely continues with the inclusion of the 90GHz data, although ~10% of the sources with GBT data show a spectral upturn from 43GHz to 90GHz. The measured polarization fractions are typically <5%, although in some cases they are measured to be up to ~20%. For the ~40% of the sample with detected polarized flux in all four bands, the polarization fractions typically increase with frequency. This trend is stronger for steeper spectrum sources as well as for the lower flux density sources.
Photometric Redshifts and Systematic Variations in the SEDs of Luminous Red Galaxies from the SDSS DR7
利用贝叶斯模板拟合方法构造了一组光谱能量分布（SED）模板，用于估算亮红星系（LRGs）的光度红移。通过检查几个公开可用的SED集的颜色属性在0<z<0.5的红移范围内，并将它们与SDSS DR 7数据进行比较，我们发现，只有一些研究的SED近似匹配的颜色的LRG数据在整个红移范围内，但不是在定量水平所需的精确光度红移。我们产生新的SED叠加模型SED的复合恒星星族与爆发模型，允许两个组件被红的灰尘，以匹配的数据在五个不同的红移箱。我们选择了一组代表LRG数据在颜色空间中的五个红移箱，从而定义了我们的新的SED模板集光度红移估计。我们用新的模板集和我们的贝叶斯模板拟合光度红移代码（PhotoZ）得到的结果几乎是无偏的，σ（Δz）=0.027（包括离群值），和一小部分灾难性离群值（|z光-z光谱|/（1+z_spec）>0.15）。我们发现，最佳描述最亮星系（-24.5<M_R<-22.7）的模板确实在z=0.1到z=0.5之间变化，与恒星星族的老化一致。此外，我们发现，最佳描述z<0.1的星系的模板作为星系绝对星等的函数存在很大差异，这表明亮度较低的星系的恒星形成活动增加。我们的研究结果的基础上测光的SDSS LRG和我们的SED模板拟合的平均SDSS LRG光谱在不同的光度和红移箱的比较支持。
QUIJOTE scientific results -- XVIII. New constraints on the polarization of the Anomalous Microwave Emission in bright Galactic regions: $ρ$\,Ophiuchi, Perseus and W43
Universidad de La Laguna（拉古纳大学）；Imperial College London（伦敦帝国理工学院）；Institut d'Astrophysique de Paris（巴黎天体物理研究所）；Universidad de Cantabria（坎塔布里亚大学）；University of Cambridge（剑桥大学）；Kavli Institute for Cosmology, University of Cambridge（剑桥大学卡弗里宇宙学研究所）；CNRS-UCB International Research Laboratory（法国国家科学研究中心-加州伯克利国际研究实验室）；The University of Manchester（曼彻斯特大学）；Xi'an Jiaotong-Liverpool University（西交利物浦大学）
UV to FIR catalogue of a galaxy sample in nearby clusters: SEDs and environmental trends
本文介绍了一个致力于研究环境对恒星形成活动影响的星系团样本。这类星系分布在星系团中，显示出丰富的特征多样性，SDSS-DR 6观测到了M_B ~ -18，GALEX AIS观测到了相当于几百万秒差距的天区。我们将从紫外到远红外的宽波段和发射线通量分配给每个星系，进行精确的光谱能量分布，以进行光谱拟合分析。星系团遵循一般的X射线光度与速度色散的关系，即L_X/sigma_c ^[4.4]。对星系密度分布的分析表明：（1）在密度分布的高密度部分，维里区和星系团外围有一个共同的范围;这可以归因于在维里区周围存在大质量星系结构（2）大质量星系团（sigma_c>550 km s^-1）的维里区呈现出一种Sigma_5分布，这种分布与相应的低质量星系团（sigma_c<550 km s ^-1）的维里区在统计上是可区分的（~96%）。大质量和低质量的星系团都遵循类似的密度-半径趋势，但低质量的星系团避免了高密度的极端。我们说明，与阿贝尔1185，星系人口的环境趋势。天空投影的星系密度图显示了低光度恒星形成星系是如何沿着比巨型星系更多的扩展结构分布的，而低光度被动星系则避开了低密度环境。巨大的被动星系和恒星形成星系共享相当相似的天空区域，被动星系表现出更集中的分布。
QUIJOTE scientific results -- XIII. Intensity and polarization study of supernova remnants in the QUIJOTE-MFI wide survey: CTB 80, Cygnus Loop, HB 21, CTA 1, Tycho and HB 9
