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The South Atlantic Anomaly (SAA) is a region of weakened geomagnetic field and in the previous studies, it shows a secular variation with time which is associated with the changing of the magnetic moment. This region also consists of large amounts of energetic charged particles and is danger to space vehicle and astronauts. Thus, it is essential to know the location and movement of the SAA. In this study, three particle monitors onboard Insight-HXMT are used to track the movement and location of the SAA from 2017 June 19 to 2019 June 19. Several particle flux maps are built to show the location of the SAA peak with time. In a grid of map, the particle count is determined by the maximum count rate and the averaged count rate, respectively. We find the results of both methods are consistent very well with each other in deriving the drift rate. The result shows the SAA peak moves westwards with an average drift rate of 0.43 ± 0.01 o /yr in longitude and moves northwards with an average drift rate of 0.17 ± 0.01 o /yr in latitude, and the drift rate is slightly larger than the result from IGRF 12 ( 0.3 o /yr) in longitude, but in latitude, the result of IGRF 12 have no obvious change with time.

We present a detailed timing study of the brightest persistent X-ray source Sco X-1 using the data collected by the Hard X-ray Modulation Telescope ( I n s i g h t -HXMT) from July 2017 to August 2018. A complete Z-track hardness-intensity diagram (HID) is obtained. The normal branch oscillations (NBOs) at ∼ 6 Hz in the lower part of the normal branch (NB) and the flare branch oscillations (FBOs) at ∼ 16 Hz in the beginning part of the flaring branch (FB) are found in observations with the Low Energy X-ray Telescope (LE) and the Medium Energy X-ray Telescope (ME) of I n s i g h t -HXMT, while the horizontal branch oscillations (HBOs) at ∼ 40 Hz and the kilohertz quasi-periodic oscillations (kHz QPOs) at ∼ 800 Hz are found simultaneously above 20 keV for the first time on the horizontal branch (HB) by the High Energy X-ray Telescope (HE) and ME. We find that for all types of the observed QPOs, the centroid frequencies are independent of energy, while the root mean square (rms) increases with energy; the centroid frequencies of both the HBOs and kHz QPOs increase along the Z-track from the top to the bottom of the HB; and the NBOs show soft phase lags increasing with energy. A continuous QPO transition from the FB to NB in ∼ 200 s are also detected. Our results indicate that the non-thermal emission is the origin of all types of QPOs, the innermost region of the accretion disk is non-thermal in nature, and the corona is nonhomogeneous geometrically.

The evidences for the influence of thermonuclear (type-I) X-ray bursts upon the surrounding environments in neutron star low-mass X-ray binaries (LMXB) were detected previously via spectral and timing analyses. Benefitting from a broad energy coverage of Insight-HXMT, we analyze one photospheric radius expansion (PRE) burst, and find an emission excess at soft X-rays. Our spectral analysis shows that, such an excess is not likely relevant to the disk reflection induced by the burst emission and can be attributed to an enhanced pre-burst/persistent emission. We find that the burst and enhanced persistent emissions sum up to exceed Eddington luminosity by ∼ 40 percentages. We speculate that the enhanced emission is from a region beyond the PRE radius, or through the Comptonization of the corona.

The elastic stiffness coefficient of Li0.02Na0.98NbO3 was measured at low temperature. Around the ferroelectric-ferroelectric phase transition temperature, the elastic stiffness behaves anomalously with a large thermal hysteresis. The result is in agreement with previous measurement on dielectric, ferroelectric and pyroelectric properties.

The ferroelectric and pyroelectric properties of Li 0.03 Na 0.97 NbO 3 crystals have been studied in the temperature range from 300 to 20 K. A large jump in the spontaneous polarization has been observed which appears at about 180 K on cooling and at about 260 K on heating. In the temperature ranges in which the spontaneous polarization jumps, the pyroelectric time response changes its polarity following a temperature variation. This unusual pyroelectric behaviour is attributed to the coexistence of two phases in the process of phase transition.