发表机构
INAF-Istituto di Radio Astronomia (IRA); Centre for Radio Astronomy Techniques and Technologies (RATT), Department of Physics and Electronics, Rhodes University; South African Radio Astronomy Observatory; INAF-Osservatorio Astronomico di Cagliari; Scuola Universitaria Superiore IUSS Pavia; INAF–Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano; Dipartimento di Fisica e Astronomia, Universitá di Bologna; Dipartimento di Fisica, Università di Trento（意大利国家天体物理研究所射电天文研究所; 罗德斯大学物理与电子学院射电天文技术与方法中心; 南非射电天文观测台; 意大利国家天体物理研究所卡利亚里天文台; 帕维亚高等大学学院; 意大利国家天体物理研究所米兰空间天体物理与宇宙物理研究所; 博洛尼亚大学物理与天文学系; 特伦托大学物理系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文利用uGMRT在1.26 GHz对24个FRB进行观测，结合文献构建75源样本，发现6个FRB场有致密射电辐射，其中4个为新PRS候选体，并计算PRS出现率，结果显示PRS更可能关联重复FRB。
AI 中文摘要
我们展示了利用升级后的巨米波射电望远镜（uGMRT）在角秒级角分辨率下对24个快速射电暴（FRBs；9个重复暴和11个一次性暴）进行的新的1.26 GHz观测，并将其与文献数据相结合，构建了一个包含75个源的扩展样本，这些源要么具有持续光度测量值，要么具有上限。我们的星表在10^29 erg s^-1 Hz^-1光度阈值以下是完备的，该阈值对应于首个发现的与FRB 20121102相关联的PRS的值。我们在六个FRB场中探测到致密射电辐射，其中两个是先前已知的PRS，四个是新候选体。这四个新候选体与三个新的重复FRB和一个看似一次性的源相关联。我们利用全部75个FRB的星表计算了PRS的出现率，发现光度大于10^29 erg s^-1 Hz^-1的PRS是罕见的。除非另有说明，所有不确定性和上限均在95%置信水平（CL）下报告。如果我们仅考虑已确认的PRS，我们发现出现率为f_all = 0.06^{+0.09}_{-0.03}，而如果同时包括PRS候选体，则得到f_all = 0.14^{+0.22}_{-0.08}。我们还计算了PRS在两类FRB（重复和非重复）中的出现率。在保守情况下，即当不考虑任何新PRS候选体与其FRB相关联时，我们发现PRS与FRB类别之间没有优先关联，重复FRB样本的出现率为f_r = 0.14^{+0.20}_{-0.09}，一次性源样本的出现率为f_nr ≤ 0.12。在包容情况下，即当所有新候选体都被视为已确认的PRS时，我们得到f_r = 0.27^{+0.21}_{-0.14}和f_nr = 0.03^{+0.14}_{-0.02}，并有边际（90% CL）证据表明PRS更倾向于与重复FRB相关联。
英文摘要
We present new $1.26$ GHz observations of 24 fast radio bursts (FRBs; 9 repeaters and 11 one-offs), conducted with the upgraded Giant Meter Wave Radio Telescope (uGMRT) at arc-second angular scale resolution, and combined them with literature data to construct an extended sample of 75 sources with either persistent luminosity measurements or upper limits. Our catalog is complete down to a $10^{29}$ erg s$^{-1}$ Hz$^{-1}$ luminosity threshold, which corresponds to the value of the first-discovered PRS, associated with FRB 20121102. We detect compact radio emission in six FRB fields, two of which are previously known PRSs and four are new candidates. The four new candidates are associated with three new repeating FRBs and one apparently one-off source. We computed the PRS occurrence using the whole catalog of 75 FRBs and found that PRSs more luminous than $10^{29}$ erg s$^{-1}$ Hz$^{-1}$ are rare. Unless otherwise stated, all uncertainties and upper limits are reported at the $95\%$ confidence level (CL). If we only consider confirmed PRSs, we find an occurrence of $f_{\rm all} = 0.06^{+0.09}_{-0.03}$, while including PRS candidates as well yields $f_{\rm all} = 0.14^{+0.22}_{-0.08}$. We also compute the PRS occurrence in the two classes of FRBs: repeating and non-repeating. In the conservative case, i.e., when none of the new PRS candidates are considered to be associated with their FRBs, we find no preferred association between the PRSs and FRB class, with an occurrence of $f_{\rm r} = 0.14^{+0.20}_{-0.09}$ for the sample of repeating FRBs and $f_{\rm nr} \leq 0.12$ for the sample of one-off sources. In the inclusive case, i.e., when all the new candidates are considered confirmed PRSs, we find $f_{\rm r} = 0.27^{+0.21}_{-0.14}$ and $f_{\rm nr} = 0.03^{+0.14}_{-0.02}$, with marginal ($90\%$ CL) evidence that PRSs are preferably associated with repeating FRBs.
Comments17 pages, 5 figures, accepted for publication in A&A
DOI：10.1051/0004-6361/202661106
