赛弗特1型星系长期中红外颜色变化的系统性研究

中文摘要 AI 辅助

我们对红移 $z < 0.3$ 的 1,977 个窄线赛弗特1型（NLSy1）星系和 4,113 个宽线赛弗特1型（BLSy1）星系进行了长期中红外（MIR）颜色变化（MCVs）的比较分析。利用14年的WISE和NEOWISE数据，我们量化了 $W1-W2$ 颜色与 $W1$ 星等之间的相关性。我们将源分为变亮变蓝（BWB）、变亮变红（RWB）以及弱/无MCV三类。我们的结果表明，BLSy1的MCV特性与NLSy1一致。这表明宿主星系污染的尘埃再处理是赛弗特1型星系中的普遍机制。热光度（$\bolL$）是MCV行为的主要驱动因素。然而，在固定的 $\bolL$ 下，RWB源的比例随着爱丁顿比率（$\redd$）的增加而减少。这揭示了吸积状态的次级依赖性。系综结构函数分析进一步表明，在给定的 $\bolL$ 下，高 $\redd$ 的源表现出更平坦的结构函数，表明尘埃环半径更小。这些发现表明，中心引擎的辐射和吸积状态塑造了环核尘埃几何结构。射电噪源与射电宁静源遵循相同的趋势，这意味着喷流发射对长期中红外变异性没有显著影响。最后，修正黑体模型表明，尺寸 $a \u2273 0.1~\u03bcm$ 的颗粒是观测到的MCVs的原因。我们的结果为赛弗特1型星系的MCVs建立了一个统一框架，其中爱丁顿比率调节了变异性模式和尘埃环的物理尺度。此外，鉴于CLAGN和RWB源的MCV分布相似，我们估计 $\u2272 6\%$ 的赛弗特1型星系可能是CLAGN候选体，这为基于中红外的预选提供了可能。

英文摘要

We present a comparative analysis of long-term mid-infrared (MIR) color variations (MCVs) for 1,977 narrow-line Seyfert 1 (NLSy1) and 4,113 broad-line Seyfert 1 (BLSy1) galaxies at $z < 0.3$. Using 14 years of WISE and NEOWISE data, we quantify the correlation between $W1-W2$ color and $W1$ magnitude. We categorize sources into bluer-when-brighter (BWB), redder-when-brighter (RWB), and weak/no MCV populations. Our results show that the MCV properties of BLSy1s are consistent with those of NLSy1s. This suggests that host-contaminated dust reprocessing is a universal mechanism across Seyfert 1s. Bolometric luminosity ($\Lbol$) is the primary driver of MCV behavior. However, at fixed $\Lbol$, the fraction of RWB sources decreases with increasing Eddington ratio ($\REdd$). This reveals a secondary dependence on the accretion state. Ensemble structure function analysis further shows that higher-$\REdd$ sources exhibit flatter structure functions at a given $\Lbol$, indicating smaller dust torus radii. These findings suggest that the central engine's radiation and accretion state shape the circumnuclear dust geometry. Radio-loud sources follow the same trends as radio-quiet counterparts, implying that jet emission does not significantly impact long-term MIR variability. Finally, modified blackbody modeling indicates that grains with sizes $a \gtrsim 0.1~μ$m are responsible for the observed MCVs. Our results establish a unified framework for MCVs in Seyfert~1s, where the Eddington ratio modulates both variability patterns and the physical scale of the dust torus. Furthermore, given the similarity between the MCV distributions of CLAGNs and RWB sources, we estimate that $\lesssim 6\%$ of Seyfert~1s may be CLAGN candidates, offering a potential MIR-based pre-selection.

发表机构

• Guangzhou University（广州大学）
• Peking University（北京大学）
• Shenzhen Technology University（深圳职业技术大学）
• University of Science and Technology of China（中国科学技术大学）
• Anhui Normal University（安徽师范大学）
• Xiamen University（厦门大学）

机构由 AI 辅助整理，请以论文原文为准。

补充信息

备注

Accepted for publication in ApJS