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In this paper, we presented a detailed analysis of the Sloan Digital Sky Survey optical spectrum of a new sub-kpc scale dual AGN candidate SDSS J222428.53+261423.2 (=SDSS J2224). The target is one of the few AGNs with all the optical narrow emission lines characterized by double-peaked profiles and with peak separations in velocity units of about 930 km s−1. If the double-peaked narrow emission lines (DPNELs) are due to a dual AGN in SDSS J2224, the estimated physical separation between the two cores is about 500 pc. Meanwhile, three alternative explanations are also discussed in this paper, however, we can not find solid evidence to completely rule them out. Our results support the presence of a sub-kpc dual AGN with DPNELs in all lines, indicating a key episode of galaxy merging evolution at sub-kpc scale. [ABSTRACT FROM AUTHOR]

The distribution of moving groups in the solar neighbourhood has been used to constrain dynamical properties of the Milky Way for decades. The kinematic bimodality between the main mode (Hyades, Pleiades, Coma Berenices, and Sirius) and Hercules can be explained by two different bar models – via the outer Lindblad resonance of a bar with a high pattern speed (∼55 km s−1 kpc−1), or via the corotation resonance of a bar with a low pattern speed (∼40 km s−1 kpc−1). Recent works directly studying the kinematics of bar stars and gas flows near the centre of the Galaxy have converged on the low pattern speed model. In this paper, we independently confirm this result by using Gaia DR3 to directly study the variation of Hercules across Galactic azimuth. We find that Hercules increases in V ϕ and becomes stronger as we move towards the minor axis of the bar, and decreases in V ϕ and becomes weaker as we move towards the major axis of the bar. This is in direct agreement with theoretical predictions of a low pattern speed bar model in which Hercules is formed by the corotation resonance with stars orbiting the bar's L4/L5 Lagrange points. [ABSTRACT FROM AUTHOR]

The jet composition of GRB plays an important role in understanding the energy dissipation and radiation mechanisms in GRB physics, but it is poorly constrained from the observational data. Recently, an interesting long-duration GRB 230307A with redshift z  = 0.065 has attracted great attention. The lack of detected thermal emission and mini-structure of prompt emission light curve of this burst suggest that the outflow is Poynting-flux-dominated and point towards the ICMART model. In this paper, we invoke two independent methods to investigate the jet composition of GRB 230307A. The high magnetization parameter (σ > 7 or ever large) for R 0 = 1010 cm that is used to suppress thermal component, strongly suggests that a significant fraction of the outflow energy is likely in a Poynting flux entrained with the baryonic matter. Moreover, it is found that the radiation efficiency of this burst for typical values ϵ e  = 0.1 and ϵ B  = 0.01 can reach as high as |$~50{{\ \rm per\ cent}}$| which disfavours the internal shock model, but is consistent with ICMART model. Finally, a possible unified picture to produce GRB 230307A originated from a compact star merger is also discussed. [ABSTRACT FROM AUTHOR]

This paper presents the first H  i results extracted from the South African Radio Astronomy Observatory (SARAO) MeerKAT Galactic Plane Survey (SMGPS) – a narrow strip (Δ b ∼ 3°) along the southern Milky Way. The primary goal consisted in tracing the great attractor (GA) wall across the innermost zone of avoidance. We reduced a segment spanning the longitude range 302° ≤ ℓ ≤ 332° for the redshift range z ≤ 0.08. The superb SMGPS sensitivity (rms = 0.3–0.5 mJy beam−1 per 44 km s−1 channel) and angular resolution (∼31″ × 26″) lead to a detection limit of log(M H  i /M⊙) ≥ 8.5 at the GA distance (⁠|$\mbox{$V_{\rm {hel}}$}\, \sim 3500{\!-\!}6500$|  km s−1). A total of 477 galaxy candidates were identified over the full redshift range. A comparison of the few H  i detections with counterparts in the literature (mostly HIZOA) found the H  i fluxes and other H  i parameters to be highly consistent. The continuation of the GA wall is confirmed through a prominent overdensity of N  = 214 detections in the GA distance range. At higher latitudes, the wall moves to higher redshifts, supportive of a possible link with the Ophiuchus cluster located behind the Galactic Bulge. This deep interferometric H  i survey demonstrates the power of the SMGPS in improving our insight of large-scale structures at these extremely low latitudes, despite the high obscuration and continuum background. [ABSTRACT FROM AUTHOR]

The article titled "Erratum: Doppler confirmation of TESS planet candidate TOI1408.01: grazing transit and likely eccentric orbit" was published in the Monthly Notices of the Royal Astronomical Society: Letters in 2023. The authors of the paper discovered that there were multiple duplicated transit lightcurves in their analysis due to a mistake. They reanalyzed the correct dataset and found that there were mostly insignificant changes to the results, with the orbital period being the most notable change. The corrected table is provided in the article. [Extracted from the article]