arXiv subjects

Dongyue Jiang

Publications and source records attributed to Dongyue Jiang.

4 recordsLinked to original sources

arXiv2026

From emission to absorption: the FAST observation of the OH 18-cm lines from the Comet C2025/A6

We observed comet C/2025 A6 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) equipped with the ultra-wideband receiver from 2025 October 23 to November 8, and it was the first detection for this comet with FAST.Through trapezoidal fitting of the OH line profiles, we derived the expansion velocities of the water which showed an increase from 1.5$\pm$0.3 km s$^{-1}$ at the heliocentric distance of 0.65 AU to 3.0$\pm$0.9 km s$^{-1}$ at 0.54 AU. Based on these results, we estimated the OH production rates of C/2025 A6 for October 23, October 26, November 4 and November 5 which were (1.0$\pm$0.1)$\times$10$^{29}$, (1.2$\pm$0.1)$\times$10$^{29}$, (1.4$\pm$0.3)$\times$10$^{29}$, and (1.5$\pm$0.4)$\times$10$^{29}$ s$^{-1}$ respectively. The results show a significant upward trend.

astro-ph.EP↗

arXiv2026

Search for Periodic Radio Signals from Double Neutron Star System Companions Using the Fast Folding Algorithm

As most of the companions in the double neutron star systems should be normal pulsars, the Fast Folding Algorithm (FFA), which is suitable for finding these long spin period pulsars, was used to search their possible radio signals. A time domain resampling code PYSOLATOR was used to maximize the available data length by removing the orbital modulation. We collected and processed 272.2 hours observational data taken by the Five-hundred-meter Aperture Spherical radio Telescope (FAST) for the 13 double neutron star systems in its sky. The signal-to-noise ratios of known pulsar signals are obviously improved by this search method, including the detection of a faint pulsar signal which only saw by folding the data. Unfortunately, no companion signals were found among all the 197962 candidates. Geodetic precession of the orbit could enhance detectability in future observations.

astro-ph.HE↗

arXiv2025

Searching for pulsars in Globular Clusters with the Fast Fold Algorithm and a new pulsar discovered in M13

We employed the Fast Folding Algorithm (FFA) on L-Band Globular Cluster (GC) observations taken with Five-hundred-meter Aperture Spherical radio Telescope (FAST) to search for new pulsars, especially those with a long rotational period. We conducted a search across 16 GCs that collectively host 93 known pulsars, as well as 14 GCs that do not contain any known pulsars. The majority of these known pulsars were successfully re-detected in our survey. The few non-detections could be attributed to the high accelerations of these pulsars. Additionally, we have discovered a new binary millisecond pulsar, namely M13I (or PSR J1641+3627I) in GC M13 (or NGC 6205), and obtained its phase-coherent timing solution using observations spanning 6 years. M13I has a spin period of 6.37 ms, and an orbital period of 18.23 days. The eccentricity of the binary orbit is 0.064, with a companion mass range of approximately 0.45 to 1.37 M$_{\odot}$. The orbital properties of M13I are remarkably different from those of the other known pulsars in M13, indicating that this pulsar has undergone a different evolutionary path compared to the rest.

astro-ph.HE↗

arXiv2025

Tomography of the Ophiuchus Molecular Cloud with Velocity Features in C$_2$H $N=1-0$ spectra: A Pilot Study of Coherent Sub-structures

The C$_2$H $N=1-0$ transition was used to investigate the possible line of sight sub-structures from the dense and optically thick in $^{13}$CO $J=1-0$ regions in the Ophiuchus star forming molecular cloud. With a 0.2 K or lower noise, multi-peak spectra were obtained and then used for identifying sub-structures. There are clues, e.g., the core velocity dispersion remains unchanged with the increasing scale that this cloud has a mild thickness in the line of sight direction and a large amount of overlapping CO cores, as expected, at least two coherent layers have been found. The integrated intensity maps of these two layers are different in shape and morphology. Inferred from the point velocity dispersion, one sub-structure with a thickness of $\sim 1$ pc was found, while other substructures were more likely to be fragments.

astro-ph.GA↗