Panchromatic spectral energy distributions of Herschel sources-猫眼课题宝

DOI：

10.1051/0004-6361/201220859

发表时间：

2013-01

期刊：

Astronomy and Astrophysics

影响因子：

6.5

通讯作者：

中科院分区：

物理与天体物理2区

文献类型：

作者：

S. Berta;D. Lutz;P. Santini;S. Wuyts;D. Rosario;D. Brisbin;A. Cooray;A. Franceschini;C. Gruppioni;E. Hatziminaoglou;Ho Seong Hwang;E. Floc’h;B. Magnelli;R. Nordon;S. Oliver;M. Page;P. Popesso;L. Pozzetti;F. Pozzi;L. Riguccini;G. Rodighiero;I. Roseboom;D. Scott;M. Symeonidis;I. Valtchanov;M. Viero;Lian-Tao Wang

将PACS进化探测器（PEP）和赫歇尔多层河外巡天（爱马仕）的远红外赫歇尔测光与GOODS-N、GOODS-S和COSMOS领域的辅助数据集相结合，可以对具有至少7-10个波段的星系的8-500 μm光谱能量分布（SED）进行采样。扩展到紫外线，光学和近红外线，波段数量增加到43。基于这个丰富的数据集，我们使用多元高斯模式的叠加，在精心选择的重构十色空间中再现了星系的分布。我们使用这个模型对星系进行分类，并建立每个类的中位数SED，然后将其与修改后的magphys代码相结合，该代码结合了恒星光，恒星加热的尘埃发射以及活动星系核（AGN）加热的可能的温暖尘埃贡献。在每一个考虑领域的星系的颜色分布可以很好地描述与6-9类的组合，跨越大范围的远红外到近红外光度比，以及不同的强度的活动星系核的贡献，测热光度。定义的高斯分组用于识别稀有或奇源。异常星系的生态学包括赫歇尔探测到的椭圆星系、非常蓝的z ~ 1 Ly-break星系、静止的旋涡星系和有星星形成的环形活动星系核。在这些群体和离群值，一个新的模板库组装，由32个SED描述的内在散射在restframe紫外到submm颜色的红外星系。该库进行了测试，对L（IR）估计与赫歇尔数据，包括，并比较eightother流行的方法，经常在文献中采用。当实施赫歇尔光度测定法时，这些方法产生在10- 20%的中值绝对偏差内彼此一致的L（IR）值，散射更多地由代码的微调而不是由SED模板的选择主导。最后，根据活动星系核含量、L（60）/L（100）颜色和L（160）/L（1.6）光度比，对PEP GOODS场中24 μm探测源进行了分类。活动星系核似乎与所有其他星系沿着分布在恒星质量（M_s）-星星形成率（SFR）空间中，而不管它们所提供的红外光度的多少，活动星系核倾向于位于“主序星”的高SFR一侧。较温暖的恒星形成源的发生率随着比星星形成率（sSFR）的增加而增加，并且它们倾向于填充M_r − SFR − z空间的“非序列”区域。

Combining far-infrared Herschel photometry from the PACS Evolutionary Probe (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES) guaranteed time programs with ancillary datasets in the GOODS-N, GOODS-S, and COSMOS fields, it is possible to sample the 8–500 μm spectral energy distributions (SEDs) of galaxies with at least 7–10 bands. Extending to the UV, optical, and near-infrared, the number of bands increases up to 43. We reproduce the distribution of galaxies in a carefully selected restframe ten colors space, based on this rich data-set, using a superposition of multivariate Gaussian modes. We use this model to classify galaxies and build median SEDs of each class, which are then fitted with a modified version of the magphys code that combines stellar light, emission from dust heated by stars and a possible warm dust contribution heated by an active galactic nucleus (AGN). The color distribution of galaxies in each of the considered fields can be well described with the combination of 6–9 classes, spanning a large range of far- to near-infrared luminosity ratios, as well as different strength of the AGN contribution to bolometric luminosities. The defined Gaussian grouping is used to identify rare or odd sources. The zoology of outliers includes Herschel-detected ellipticals, very blue z ~ 1 Ly-break galaxies, quiescent spirals, and torus-dominated AGN with star formation. Out of these groups and outliers, a new template library is assembled, consisting of 32 SEDs describing the intrinsic scatter in the restframe UV-to-submm colors of infrared galaxies. This library is tested against L(IR) estimates with and without Herschel data included, and compared to eightother popular methods often adopted in the literature. When implementing Herschel photometry, these approaches produce L(IR) values consistent with each other within a median absolute deviation of 10–20%, the scatter being dominated more by fine tuning of the codes, rather than by the choice of SED templates. Finally, the library is used to classify 24 μm detected sources in PEP GOODS fields on the basis of AGN content, L(60)/L(100) color and L(160)/L(1.6) luminosity ratio. AGN appear to be distributed in the stellar mass (M_∗) vs. star formation rate (SFR) space along with all other galaxies, regardless of the amount of infrared luminosity they are powering, with the tendency to lie on the high SFR side of the “main sequence”. The incidence of warmer star-forming sources grows for objects with higher specific star formation rates (sSFR), and they tend to populate the “off-sequence” region of the M_∗ − SFR − z space.

Panchromatic spectral energy distributions of Herschel sources

文献摘要

被引文献

相似文献