论文标题
确定Egret未识别的伽马射线源中的K4000潜在的Blazar候选者
Determination of K4000 of potential blazar candidates among EGRET unidentified gamma-ray sources
论文作者
论文摘要
Blazars是无线电大声的活跃银河核（AGN），其相对论喷气机针对观察者的视线。根据它们的光谱，Blazars可以归类为平面无线电类星体（FSRQ）或BL LACS。 FSRQ是更具发光的大麻，具有狭窄和宽发射和吸收线，而Bl lacs则较不发光且无特征。最近的研究表明，Blazars占主导地位（93％）已经识别出的白皮书来源（142），这表明在身份不明的来源（129）中，仍然可能有微弱的大麻。由于喷气机内存在强的非热成分，因此发现大叶片在4000Å时表现出较弱的抑郁症（K4000 <0.4）。在这项研究中，我们旨在确定来自未识别的白皮书来源的潜在的Blazar候选者中选定样本的K4000中断，以确认其大型菜单。我们分别使用了与无线电对应器相关的两个Blazar候选者，分别是3EGJ1800-0146和3EGJ1709-0817，J1802-0207和J1713-0817。他们的光学对应物是通过在南非南非南非大型望远镜（SALT）的Robert Stobie光谱仪（RSS）进行的光谱观察获得的。在这些来源的光谱中，观察到的Ca II H＆K线抑制在4000Å处显示出浅抑郁症，K4000 = 0.35+-0.02和0.24+-0.01，这表明这些来源是Blazar候选者。此外，在光谱中测得的红移z = 0.165和0.26证实了这些来源的外乳外性质。 关键字：线：识别，辐射机制：非热，技术：光谱，星系：活动，星系：喷气机，星系：Bl lacertae对象
Blazars are radio-loud Active Galactic Nuclei (AGN) with relativistic jets oriented towards the observer's line-of-sight. Based on their optical spectra, blazars may be classified as flat-spectrum radio quasars (FSRQs) or BL Lacs. FSRQs are more luminous blazars with both narrow and broad emission and absorption lines, while BL Lacs are less luminous and featureless. Recent studies show that blazars dominate (93%) the already-identified EGRET sources (142), suggesting that among the unidentified sources (129) there could still be faint blazars. Due to the presence of a strong non-thermal component inside their jets, blazars are found to display a weaker depression at 4000 Å (K4000<0.4). In this study, we aimed at determining the K4000 break for a selected sample among the potential blazar candidates from unidentified EGRET sources to confirm their blazar nature. We used two blazar candidates, 3EGJ1800-0146 and 3EGJ1709-0817 associated with radio counterparts, J1802-0207 and J1713-0817, respectively. Their optical counterparts were obtained through spectroscopic observations using Robert Stobie spectrograph (RSS) at the Southern African Large Telescope (SALT) in South Africa. The observed Ca II H & K lines depression at 4000 Å in spectra of these sources show a shallow depression, K4000=0.35+-0.02 and 0.24+-0.01, respectively, suggesting that these sources are blazar candidates. Moreover, the redshifts z=0.165 and 0.26 measured in their spectra confirm the extragalactic nature of these sources. Keywords: line: identification, radiation mechanisms: non-thermal, techniques: spectroscopic, galaxies: active, galaxies: jets, galaxies: BL Lacertae objects
