发表机构
Seoul National University; Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences; Peking University; University of Vienna; NRC Herzberg Astronomy and Astrophysics; University of Victoria（首尔大学; 孔科利天文台，HUN-REN地球与天文学研究中心; 北京大学; 维也纳大学; 国家研究委员会赫茨伯格天体物理学研究所; 维多利亚大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
在猎户座 L1641 星团中发现 PR Ori B 发生 FU Ori 型爆发，通过多波段光谱和测光证实其驱动 ΔG=5 星等爆发，光度约 30-40 太阳光度，是近几十年来最接近最亮的 FUor 之一。
AI 中文摘要
我们报告在猎户座恒星形成区的 L1641 星团中发现了一次邻近的 FU Ori 型爆发（FUor），即 PR Ori B。这种高振幅的变率最初是在未分辨的 PR Ori 双星系统的 NEOWISE（3-5 微米）测光中识别出来的。长期的、分辨的光学测光监测表明，PR Ori B 是 ΔG=5 星等爆发的驱动者，而 PR Ori A 在过去 20 年中保持恒定。PR Ori B 的近红外光谱从静止期的晚 K 型光谱型转变为爆发期的黏性加热盘，包括在 $^{12}$CO 和 H$_2$O 波段的深吸收。光学光谱也展现出通常与 FUor 相关的特征，包括 Na I D 线的 P Cygni 轮廓和 Ca II 红外三重线的吸收。爆发的光度（L$_{acc}$~30--40 L$_\bigodot$）与 FUor 中常见的光度相似。Spitzer/IRS 和 VLT/VISIR 光谱的比较显示，在爆发期间存在硅酸盐结晶的一些证据。PR Ori B 是过去几年中发现的最接近和最亮的 FUor 之一，仅比该类原型 FU Ori 暗一个星等。其邻近性和亮度将允许未来的高角分辨率观测来探测内盘物理，并评估由于光度增加而导致的盘的变化。
英文摘要
We report the discovery of a nearby FU Ori-type outburst (FUor), PR Ori B, in the L1641 cluster of the Orion star-forming region. The high-amplitude variability was first identified in the NEOWISE (3-5 $μ$m) photometry of the unresolved PR Ori binary system. Long-term, resolved optical photometric monitoring demonstrates that PR Ori B is the driver of a $ΔG=5~$mag outburst, while PR Ori A has remained constant over the last 20 years. The near-IR spectrum of PR Ori B changes from a late K-type spectral type during quiescence to a viscously heated disk during outburst, including deep absorption in $^{12}$CO and H$_2$O bands. The optical spectrum also exhibits features that are commonly associated with FUors, including P Cygni profiles in Na I D lines and absorption in the Ca II infrared triplet. The luminosity of the outburst (L$_{acc}\sim$30--40 L$_\odot$) is similar to that commonly observed in FUors. The comparison of Spitzer/IRS and VLT/VISIR spectroscopy shows some evidence of silicate crystallisation during the outburst. PR Ori B is one of the closest and brightest FUors discovered over the last few years, only one magnitude fainter than the archetype of the class FU Ori. The proximity and brightness will allow for future high angular resolution observations to probe the physics of the inner disk and to evaluate changes in the disk due to the increased luminosity.
Comments23 pages, 16 figures, 3 tables. Accepted for publication at ApJ
