标题： 亮红外星系和超亮红外星系的8至13微米光谱 显示英文标题

标题： 8--13 micron spectroscopy of luminous and ultraluminous infrared galaxies

摘要： 新近展示了27个红外星系在10微米的中等分辨率中红外光谱。 这些星系是从三个60微米选择的完整流量受限星系目录和一个12微米选择的完整流量受限星系目录中选出的； 其中17个源的L_IR(8--1000微米) >= 5乘以10^11 L_sun。 还展示了源Arp 299B1的高分辨率光谱。 结合这些新结果与之前发表的结果，定义了一个几乎完整的60微米选的流量受限子样本，其中有25个星系的L_IR(8--1000微米) >= 1.6乘以10^11 L_sun。 在这个子样本内，根据大多数光谱中清晰存在的11.3微米芳烃发射特征，发现在亮度范围1.6乘以10^11到10^{12}L_sun内的红外星系的主要能源是大质量恒星形成。 这个子样本中的五个超亮红外星系中有三个显示出活动星系核提供了重要的能量来源的证据，这是基于其中红外光谱中硅酸盐吸收的检测。 讨论了11.3微米特征当量宽度与红外光到分子气体质量比之间可能存在的反相关性的物理基础。 显示英文摘要

摘要： New moderate-resolution mid-infrared spectroscopy at 10 micron of 27 infrared galaxies is presented. The galaxies have been chosen from three 60 micron selected and one 12 micron selected complete flux-limited catalogs of galaxies; 17 of these sources have L_IR(8--1000 micron) >= 5 times 10^11 L_sun. A high-resolution spectrum of the source Arp 299B1 is also presented. Combining these new results with previously published results, a nearly complete 60 micron selected flux limited subsample, with L_IR(8--1000 micron) >= 1.6 times 10^11 L_sun of 25 galaxies is defined. Within this subsample, it is found that the dominant power source of infrared galaxies in the luminosity range 1.6 times 10^11 < L_IR(8--1000 micron) < 10^{12} L_sun is massive star formation based on the clear presence of the 11.3 micron aromatic hydrocarbon emission feature in the majority of the spectra. Three of the five ultraluminous infrared galaxies (L_IR(8--1000 micron) >= 10^12 L_sun) within this subsample show evidence that an active galactic nucleus provides an energetically important power source based on the detection of silicate absorption in their mid-infrared spectra. The physical basis of a possible anti-correlation between the 11.3 micron feature equivalent width and infrared light to molecular gas mass ratios is discussed.