AI 中文总结
本文由Lasair-ZTF证认红移0.2267的LFBOTs AT 2024qfm，其光度和衰减与AT 2018cow匹配，还提及LSST将提升LFBOTs巡天能力及探测其快速演化的挑战。
AI 中文摘要
明亮快速蓝光学瞬变源（LFBOTs）的辐射覆盖从X射线到射电波段，典型代表是在距离65兆秒差距的宿主星系中发现的AT 2018cow。在随后的8年里，又发现了11个LFBOTs，红移范围为0.075 ≤ z ≤ 0.34，还有一个是从2016年的数据中回溯证认的。本文介绍AT 2024qfm的发现，它被证认为LFBOTs，所在宿主星系的红移为z = 0.2267 ± 0.0002。其紫外到光学波段的光度以及13天的快速衰减过程与AT 2018cow高度吻合。我们描述了该瞬变源是如何通过Lasair broker中的自定义滤波器，在Zwicky瞬变设施（ZTF）的警报流中被证认的，该滤波器用于标记随时间变化的流量梯度。使用相同方法还证认了另一个LFBOT候选体（AT 2024kth）。LFBOTs的物理起源仍存在争议，尚无明确共识，进一步的研究需要更多发现、宿主星系表征以及多波段分析来约束理论。我们结合鲁宾天文台的空间和时间遗产巡天（LSST）的背景讨论本次发现，LSST的灵敏度将使LFBOTs的有效巡天体积相比ZTF扩大10倍，覆盖红移z ≤ 0.6的范围，且我们的FastFinder滤波器能够探测到这类事件。我们强调，要以足够低的延迟探测其快速演化，从而触发能约束理论模型的多波段后续观测，这一过程面临挑战。
英文摘要
Luminous fast blue optical transients (LFBOTs) emit from x-ray to radio wavelengths, epitomised by the discovery of AT 2018cow in a host galaxy at 65 Mpc. In the following eight years eleven more have been found, at redshifts $0.075 \lesssim z \lesssim0.34$, plus one identified retrospectively from 2016. Here we present the discovery of AT 2024qfm, classified as an LFBOT in a host galaxy at $z = 0.2267 \pm 0.0002$. Its ultraviolet-to-optical luminosity and rapid 13 day fade closely match AT 2018cow. We describe how the transient was identified in the Zwicky Transient Facility alert stream using a custom filter in the Lasair broker that flags flux gradients over time. Another LFBOT candidate was identified with the same methodology (AT 2024kth). The physical origin of LFBOTs remains debated with no firm consensus, and further progress requires more discoveries, host-galaxy characterisation, and multi-wavelength analysis to constrain theory. We discuss this discovery in the context of Rubin Observatory's Legacy Survey of Space and Time (LSST), whose sensitivity will increase the effective LFBOT survey volume tenfold relative to ZTF, out to $z \lesssim 0.6$, and show that our FastFinder filter could recover such events. We highlight the challenge of detecting their fast evolution with sufficiently low latency to trigger multi-wavelength follow-up that can constrain theoretical models.
CommentsSubmitted to MNRAS. 11 pages with 5 figures and 3 tables (incl., Appendices)
