arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0810.1293astro-ph
收藏

SWIRE场中z~2亮星暴的MAMBO 1.2毫米观测

MAMBO 1.2mm observations of luminous starbursts at z~2 in the SWIRE fields

C. J. Lonsdale, M. Polletta, A. Omont, D. Shupe, S. Berta, R. Zylka, B. Siana, D. Lutz, D. Farrah, H. E. Smith, G. Lagache, C. De Breuck, F. Owen, A. Beelen, D.… 展开作者

C. J. Lonsdale, M. Polletta, A. Omont, D. Shupe, S. Berta, R. Zylka, B. Siana, D. Lutz, D. Farrah, H. E. Smith, G. Lagache, C. De Breuck, F. Owen, A. Beelen, D. Weedman, A. Franceschini, D. Clements, L. Tacconi, A. Afonso-Luis, I. Perez-Fournon, P. Cox, F. Bertoldi

摘要:

我们报告在-关闭指出MAMBO观测在1.2毫米的61斯皮策选择恒星形成星系的SWIRE调查。根据亮24 μ m通量(f_24 μ m>0.4mJy)和恒星主导的近红外光谱能量分布选择了有利于z~2星暴星系的源。整个样品的平均1.2mm通量为1.5+/-0.2mJy。我们的分析集中在洛克曼洞场的29个源,其中平均1.2 mm通量(1.9+/-0.3 mJy)高于其他场(1.1+/-0.2 mJy)。对源的多波长光谱能量分布的分析表明,它们是星暴星系,远红外光度约为10^12-10^13.3 Lsun,恒星质量约为0.2-6 x10^11 Msun。与亚毫米选择星系(SMG)相比,SWIRE-MAMBO源是具有最大24 μ m/毫米通量比的源之一。通过比较SWIRE-MAMBO源和SMG的平均中红外光谱和堆叠的远红外光谱能量分布,研究了这种大比率的起源。中红外光谱表现出强烈的PAH功能,和一个温暖的尘埃连续。温暖的尘埃连续体贡献了约34%的中红外辐射,并且可能与活动星系核成分有关。这一结论与SMG中发现的一致。24 μ m/1.2mm的大通量比因此不是由于活动星系核的发射,而是由于与SMG相比增强的PAH发射。堆叠的远红外通量的分析产生温暖的尘埃温度比通常观察到的SMG。我们的选择有利于温暖的超亮红外光源在高z,一类对象,很少发现SMG样本。我们的样品是目前可用的最大的斯皮策选择的毫米波长检测样品。

英文摘要:

We report on--off pointed MAMBO observations at 1.2 mm of 61 Spitzer-selected star-forming galaxies from the SWIRE survey. The sources are selected on the basis of bright 24um fluxes (f_24um>0.4mJy) and of stellar dominated near-infrared spectral energy distributions in order to favor z~2 starburst galaxies. The average 1.2mm flux for the whole sample is 1.5+/-0.2 mJy. Our analysis focuses on 29 sources in the Lockman Hole field where the average 1.2mm flux (1.9+/-0.3 mJy) is higher than in other fields (1.1+/-0.2 mJy). The analysis of the sources multi-wavelength spectral energy distributions indicates that they are starburst galaxies with far-infrared luminosities ~10^12-10^13.3 Lsun, and stellar masses of ~0.2-6 x10^11 M_sun. Compared to sub-millimeter selected galaxies (SMGs), the SWIRE-MAMBO sources are among those with the largest 24um/millimeter flux ratios. The origin of such large ratios is investigated by comparing the average mid-infrared spectra and the stacked far-infrared spectral energy distributions of the SWIRE-MAMBO sources and of SMGs. The mid-infrared spectra exhibit strong PAH features, and a warm dust continuum. The warm dust continuum contributes to ~34% of the mid-infrared emission, and is likely associated with an AGN component. This constribution is consistent with what is found in SMGs. The large 24um/1.2mm flux ratios are thus not due to AGN emission, but rather to enhanced PAH emission compared to SMGs. The analysis of the stacked far-infrared fluxes yields warmer dust temperatures than typically observed in SMGs. Our selection favors warm ultra-luminous infrared sources at high-z, a class of objects that is rarely found in SMG samples. Our sample is the largest Spitzer-selected sample detected at millimeter wavelengths currently available.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑