arXiv subjects

Jianbin Weng

Publications and source records attributed to Jianbin Weng.

3 recordsLinked to original sources

arXiv2026

Chandra and XMM-Newton X-ray Study on the Core-collapse Supernova Remnant N63A in an H II Region

N63A is one of the brightest supernova remnants (SNRs) in the Large Magellanic Cloud and provides an excellent laboratory for studying SNR evolution in an H II region. We present a detailed X-ray analysis of N63A using Chandra and XMM-Newton observations, combining both imaging and high-resolution spectroscopy. Our global spectral fitting reveals three distinct thermal plasma components with temperatures $kT$$\sim$0.3, 0.7, and 1.5 keV. Spatially-resolved spectroscopy with Chandra shows substantial variations in physical parameters across the remnant, with the eastern lobes of the optical nebula exhibiting significantly higher ionization timescales than the western region. These multi-temperature plasma components indicate that N63A is evolving in a cloudy interstellar medium: the low-temperature component arises from evaporated dense cloudlets that are engulfed by the blast wave, the intermediate-temperature component represents shocked inter-cloud medium, and the highest-temperature component likely results from the shocks reflected by the clouds. We estimate a Sedov age of approximately 4.5 kyr and an explosion energy of about $4\times10^{51}$ erg. Comparison of the observed abundance ratios and masses of metal elements with the nucleosynthesis models constrains the progenitor mass to approximately $20 M_{\odot}$, supporting a single-star core-collapse origin for N63A.

astro-ph.HE↗

arXiv2024

Upper Limits of $^{44}$Ti Decay Emission in Four Nearby Thermonuclear Supernova Remnants

To identify progenitors and investigate evidence of He burning, we searched for decay radiation of freshly synthesized $^{44}$Ti in four young nearby thermonuclear supernova remnants: Kepler, SN 1885, G1.9+0.3 and SN 1006, by analysing the up-to-date NuSTAR archival data. No apparent flux excess from the 68 and 78 keV line emissions accompanying decay was detected above the power law continuum applied for the remnants and the absorbed stray light. By comparing the inferred upper limits of the line flux and the initial $^{44}$Ti masses with a wide variety of supernova nucleosynthesis models, we placed constraints on the supernova progenitors. We derived the first NuSTAR line flux upper limit for Kepler and ruled out most of the double-detonation scenarios with a thick He layer under low density. We estimated, for the first time, the upper limit for SN 1885, which is high because of the large distance yet still remains consistent with the He shell detonation. The new flux and mass limit of G1.9+0.3 derived from a longer total exposure is lower than the results from previous studies and evidently excludes explosive burning of He-rich matter. The relatively advanced age and the large spatial extent of SN 1006 have prevented meaningful constraints.

astro-ph.HE↗

arXiv2021

Spatially Resolved X-ray Study of Supernova Remnant G306.3$-$0.9 with Unusually High Calcium Abundance

G306.3$-$0.9 is an asymmetric Galactic supernova remnant (SNR), whose progenitor has been thought to be a Type Ia supernova (SN), but its high Ca abundance appears inconsistent with the Type Ia origin. Hoping to uncover the reason for its asymmetry and the origin of this SNR, we performed a spatially resolved X-ray spectroscopic analysis of XMM-Newton and Chandra observation data. We divided the SNR into 13 regions and analyzed the spectra using two-temperature models (0.2 keV + 1 keV). Compared to the southwestern regions, the northeastern regions have higher metal abundances and a lower gas density. This suggests that the asymmetric morphology results from the non-uniform ambient environment. We found that neither Type Ia nor core-collapse SN models can account for the abnormally high abundance ratios of Ar/Si, Ca/Si, or the shape of the abundance curve. A comparison with the Ca-rich transient models shows that G306.3$-$0.9 is likely to be the first identified Galactic "Ca-rich transient" remnant, although the theoretical production of element S is lower. We also note that the conclusion for the SNR's origin relies on the measured abundance ratios and existing nucleosynthesis models. Between two groups of Ca-rich transient explosion models, we prefer the He shell detonation for an accreting WD, rather than the merger of a white dwarf and a neutron star.

astro-ph.HE↗