论文标题
搜索$γ$ - 从本地宇宙样本中的低频选定的射电星系排放
A search for $γ$-ray emission from a sample of local universe low-frequency selected radio galaxies
论文作者
论文摘要
宽度星系是罕见的$γ$射线发射器，只有Fermi-lat检测到低红移射电星系。但是，它们为活动星系的排放机制提供了潜在的见解，尤其是当它们的喷气机相对于地球的对准意味着，与Blazars不同，它们的发射不一定是射流主导的。我们使用Fermi-LAT数据对Bologna完整样本中的78个射电星系进行无偏见的调查，以搜索新的$γ$ ray-ray发射射电星系。我们观察到该样品中包含的6个已知的Fermi-LAT检测到的射电星系中的4个中有统计学意义的$γ$ - 射线排放，并找到一些证据，证明了$γ$ - 雷的发射在空间上与4个以前未被发现的射电星系相吻合。当搜索大型参数空间时，我们计算一个概率分布来计算else-elsewere效果。我们发现，这4个在空间上重合的亚阈值$γ$ - 雷过剩很可能是偶然的关联，并且不太可能是射电星系排放的。计算了未观察到$γ$ ray发射的射线星系的上限。
Radio galaxies are uncommon $γ$-ray emitters, and only low redshift radio galaxies are detected with Fermi-LAT. However, they offer potential insights into the emission mechanisms of active galaxies, particularly as the alignment of their jets with respect to the Earth means that, unlike blazars, their emission is not necessarily jet-dominated. We use Fermi-LAT data to perform an unbiased survey of 78 radio galaxies from the Bologna Complete Sample in order to search for new $γ$-ray-emitting radio galaxies. We observe statistically significant $γ$-ray emission from 4 of the 6 known Fermi-LAT detected radio galaxies included in this sample, and find some evidence for $γ$-ray emission spatially coincident with 4 previously undetected radio galaxies. As a large parameter space is searched, we calculate a probability distribution to compute the look-elsewhere effect. We find that these 4 spatially coincident sub-threshold $γ$-ray excesses are most likely a chance association, and are unlikely to be emission from the radio galaxies. Upper limits on flux are calculated for the radio galaxies from which no $γ$-ray emission is observed.
