Insight-HXMT observations of Swift J0243.6+6124 during its 2017-2018 outburst

The recently discovered neutron star transient Swift J0243.6+6124 has been monitored by {\it the Hard X-ray Modulation Telescope} ({\it Insight-\rm HXMT). Based on the obtained data, we investigate the broadband spectrum of the source throughout the outburst. We estimate the broadband flux of the source and search for possible cyclotron line in the broadband spectrum. No evidence of line-like features is, however, found up to $\rm 150~keV$. In the absence of any cyclotron line in its energy spectrum, we estimate the magnetic field of the source based on the observed spin evolution of the neutron star by applying two accretion torque models. In both cases, we get consistent results with $B\rm \sim 10^{13}~G$, $D\rm \sim 6~kpc$ and peak luminosity of $\rm >10^{39}~erg~s^{-1}$ which makes the source the first Galactic ultraluminous X-ray source hosting a neutron star.Comment: publishe

Overview to the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite

As China's first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band (1-250 keV) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 MeV. It was designed to perform pointing, scanning and gamma-ray burst (GRB) observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be reconstructed. Here we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results.Comment: 29 pages, 40 figures, 6 tables, to appear in Sci. China-Phys. Mech. Astron. arXiv admin note: text overlap with arXiv:1910.0443

Candidemia caused by Candida haemulonii: a case report and literature review in neonates

Candidemia poses a significant challenge for hospitalized neonates with an increase in morbidity and mortality. However, candidemia caused by Candida haemulonii in newborns is rare but fatal. We report such a case in China and performed a literature review. A neonate with a gestational age of 31+6 weeks and a birth weight of 1,420g was diagnosed with C. haemulonii candidemia. The infectious agent was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and sequencing of the internal transcribed spacer region. The in vitro antifungal susceptibility testing indicated high minimal inhibitory concentrations for fluconazole (>128 µg/mL), voriconazole (>8 μg/mL), and amphotericin B (>4 µg/mL). Fortunately, the newborn was successfully treated with fluconazole. After a literature review of C. haemulonii candidemia, we found that the risk factors of the candidemia might involve premature, low birth weight, invasive therapeutic devices, broad-spectrum antimicrobial agents, and parenteral nutrition infusion. This study will broaden our knowledge on neonatal candidemia caused by C. haemulonii