首次 MeerKAT S 波段球状星团脉冲星巡天
The first MeerKAT S-band globular cluster pulsar survey
- University of Cagliari(卡利亚里大学)
- INAF – Astronomical Observatory of Cagliari (OAC)(意大利国家天体物理研究所 - 卡利亚里天文台(OAC))
- Fakultät für Physik, Universität Bielefeld(比勒费尔德大学物理学院)
- Max-Planck-Institut für Radioastronomie(马克斯·普朗克射电天文研究所)
- National Radio Astronomy Observatory(美国国家射电天文台)
- Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, The University of Manchester(曼彻斯特大学物理与天文学系乔德雷尔银行天体物理学中心)
机构由 AI 辅助整理,请以论文原文为准。
AI总结:
首次 MeerKAT S 波段巡天搜索 14 个球状星团,重新探测 39 颗已知脉冲星并新发现 4 颗毫秒脉冲星,验证了高频搜索在强色散环境中的有效性。
AI中文摘要:
球状星团是回收脉冲星的高效工厂,但对高色散量(DM)星团的搜索在约 1 GHz 频率下会因色散展宽和星际散射而受到严重限制。我们首次报道了对 14 个球状星团进行的 MeerKAT S 波段(ν ~ 2.4 GHz)脉冲星巡天。利用高时间分辨率和频率分辨率的观测数据,我们采用分段加速度和加加速度技术进行搜索,随后进行候选体折叠,并利用已有的计时星历表进行针对性折叠。我们重新探测到 39 颗已知脉冲星,并在 Glimpse-C01 中新发现 4 颗毫秒脉冲星:J1848-0129C、D、E 和 F。多历元跟踪观测使得我们能够对 J1848-0129C 和 J1848-0129D 进行初步的开普勒轨道拟合。J1848-0129C 是一颗处于约 5 天轨道周期的食双星毫秒脉冲星,属于被称为“猎人双星”的长周期食双星系统;而 J1848-0129D 则处于约 3.4 天的近圆轨道,其伴星是一颗质量约为 1 个太阳质量的大质量白矮星。Glimpse-C01 中的两颗脉冲星显示出与星团平均色散量存在显著偏差。与其他银河系球状星团的比较表明,星团内色散量弥散往往随前景色散量增加而增大,这意味着窄色散量搜索窗口可能不适用于高色散量星团。基于探测和非探测结果,我们推断 MeerKAT S 波段绑定阵列单历元实际可探测性尺度约为 10-20 微央斯基。这些结果证明了在强色散和强散射的星团环境中进行高频搜索脉冲星的价值。
英文摘要:
Globular clusters are efficient factories of recycled pulsars, but searches toward high-dispersion-measure (DM) clusters can be strongly limited near 1 GHz by dispersive smearing and interstellar scattering. We present the first MeerKAT S-band (nu ~ 2.4 GHz) pulsar survey of 14 globular clusters. High time- and frequency-resolution observations were searched using segmented acceleration and jerk techniques, followed by candidate folding and targeted folding with available timing ephemerides. We re-detected 39 known pulsars and discovered four new millisecond pulsars in Glimpse-C01: J1848-0129C, D, E, and F. Multi-epoch follow-up enabled preliminary Keplerian orbital fits for J1848-0129C and J1848-0129D. J1848-0129C is an eclipsing MSP in a ~5 d orbit, placing it among long-period eclipsing systems known as huntsman binaries, while J1848-0129D is in a ~3.4 d nearly circular orbit with a massive white-dwarf companion of about 1 solar mass. Two Glimpse-C01 pulsars show large DM offsets from the cluster average. Comparison with other Galactic globular clusters indicates that intracluster DM spreads tend to increase with foreground DM, implying that narrow DM search windows may be sub-optimal for high-DM clusters. From detections and non-detections, we infer a practical single-epoch MeerKAT S-band tied-array detectability scale of about 10-20 microJy. These results demonstrate the value of high-frequency searches for pulsars in strongly dispersed and scattered cluster environments.