Author: "Ou, G." - Searchworks@Jio Institute Digital Library Search Results

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706 results on '"Ou, G."'

1. Integrated Bioinformatic Analysis and Validation Identifies Immune Microenvironment-Related Potential Biomarkers in Alzheimer’s Disease

Author: Yang, F., Zhang, N., Ou, G.-Y., and Xu, Shu-wen
Published: 2024
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2. Inhibitory Effect of P22077 on Airway Inflammation in Rats with COPD and Its Mechanism

Author: Zeng D, Zhang W, Chen X, Ou G, Huang Y, and Yu C
Subjects: copd, ubiquitinase inhibitors, p22077, airway inflammation, nlrp3., Diseases of the respiratory system, RC705-779
Abstract: Di Zeng,1,&ast; Wenbo Zhang,2,&ast; Xiaoju Chen,3 Guochun Ou,4 Yuewei Huang,2 Chengxiu Yu2 1Department of General Practice, The Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, 637000, People’s Republic of China; 2Department of Respiratory and Critical Care Medicine, The Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, 637000, People’s Republic of China; 3Clinical Medical College, Affiliated Hospital of Chengdu University, Chengdu, Sichuan, 610081, People’s Republic of China; 4Department of Respiratory and Critical Care Medicine, Suining Central Hospital, Suining, Sichuan, 629000, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Xiaoju Chen, Clinical Medical College, Affiliated Hospital of Chengdu University, Chengdu, Sichuan, 610081, People’s Republic of China, Email 13989185102@sina.cnPurpose: Here, we studied the pharmacological effect of P22077 on airway inflammation induced by lipopolysaccharide and cigarette smoke and explored the therapeutic mechanism of P22077 in COPD model RAT.Patients and Methods: The COPD model was established by lipopolysaccharide combined with fumigation; animals were treated with vehicle or P22077. Serum, bronchoalveolar lavage fluid (BALF), and lung tissues were collected for analysis.Results: Our results showed that P22077 treatment significantly improved the airway inflammation of COPD model RAT and reduced the recruitment of leukocytes in BALF, and hypersecretion of interleukin-18 (IL-18), interleukin-1β (IL-1β) in BALF and serum. H&E staining showed that P22077 treatment could effectively reduce emphysema, immune cell infiltration and airway wall destruction. PAS staining showed that The proliferation of cup cells in the airway wall and the number of bronchial cup cells were significantly reduced in rats treated with P22077. In addition, we found that P22077 treatment suppressed the generation of the NLRP3/ASC/Caspase 1 inflammasome complex to inhibit the inflammatory response caused by IL-1β and IL-18.Conclusion: Conclusion: P22077 inhibits expression of NLRP3 pathway-related inflammatory factors and proteins and reduces the airway inflammatory response and inflammatory cell aggregation in COPD rats. The underlying mechanism may be related to the down-regulation of NLRP3 inflammatory vesicle signaling pathway expression.Keywords: COPD, ubiquitinase inhibitors, P22077, airway inflammation, NLRP3
Published: 2024

3. Peculiar disk behaviors of the black hole candidate MAXI J1348-630 in the hard state observed by Insight-HXMT and Swift

Author: Zhang, W., Tao, L., Soria, R., Qu, J. L., Zhang, S. N., Weng, S. S., zhang, L., Wang, Y. N., Huang, Y., Ma, R. C., Zhang, S., Ge, M. Y., Song, L. M., Ma, X., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Liu, X. J., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yang, Y. R., Yi, Q. B., Yin, Q. Q., Yuan, Y., Zhang, F., Zhang, H. M., Zhang, P., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a spectral study of the black hole candidate MAXI J1348-630 during its 2019 outburst, based on monitoring observations with Insight-HXMT and Swift. Throughout the outburst, the spectra are well fitted with power-law plus disk-blackbody components. In the soft-intermediate and soft states, we observed the canonical relation L ~ T_in^4 between disk luminosity L and peak colour temperature T_in, with a constant inner radius R_in (traditionally identified with the innermost stable circular orbit). At other stages of the outburst cycle, the behaviour is more unusual, inconsistent with the canonical outburst evolution of black hole transients. In particular, during the hard rise, the apparent inner radius is smaller than in the soft state (and increasing), and the peak colour temperature is higher (and decreasing). This anomalous behaviour is found even when we model the spectra with self-consistent Comptonization models, which take into account the up-scattering of photons from the disk component into the power-law component. To explain both those anomalous trends at the same time, we suggest that the hardening factor for the inner disk emission was larger than the canonical value of ~1.7 at the beginning of the outburst. A more physical trend of radii and temperature evolution requires a hardening factor evolving from ~3.5 at the beginning of the hard state to ~1.7 in the hard intermediate state. This could be evidence that the inner disk was in the process of condensing from the hot, optically thin medium and had not yet reached a sufficiently high optical depth for its emission spectrum to be described by the standard optically-thick disk solution., Comment: 20 pages, 10 figures, 4 tables, accepted by ApJ
Published: 2022
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4. GECAM detection of a bright type-I X-ray burst from 4U 0614+09: confirmation its spin frequency at 413 Hz

Author: Chen, Y. P., Li, J., Xiong, S. L., Ji, L., Zhang, S., Peng, W. X., Qiao, R., Li, X. Q., Wen, X. Y., Song, L. M., Zheng, S. J., Song, X. Y., Zhao, X. Y., Huang, Y., Lu, F. J., Zhang, S. N., Xiao, S., Cai, C., Zhang, B. X., An, Z. H., Chen, C., Chen, G., Chen, W., Dai, G. Q., Du, Y. Q., Gao, M., Gong, K., Guo, D. Y., Guo, Z. W., He, J. J., Li, B., Li, C., Li, C. Y., Li, G., Li, J. H., Li, L., Li, Q. X., Li, X. B., Li, Y. G., Liang, J., Liang, X. H., Liao, J. Y., Liu, J. C., Liu, X. J., Liu, Y. Q., Luo, Q., Ma, X., Meng, B., Ou, G., Shi, D. L., Shi, F., Shi, J. Y., Sun, G. X., Sun, X. L., Tuo, Y. L., Wang, C. W., Wang, H., Wang, H. Y., Wang, J., Wang, J. Z., Wang, P., Wang, Y. S., Wang, Y. X., Wen, X., Wu, H., Xie, S. L., Xu, Y. B., Xu, Y. P., Xue, W. C., Yang, S., Yao, M., Ye, J. Y., Yi, Q. B., Zhang, C. M., Zhang, C. Y., Zhang, D. L., Zhang, Fan, Zhang, Fei, Zhang, H. M., Zhang, K., Zhang, P., Zhang, X. L., Zhang, Y. Q., Zhang, Z., Zhao, G. Y., Zhao, S. Y., Zhao, Y., Zheng, C., Zhou, X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: One month after launching Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM), a bright thermonuclear X-ray burst from 4U~0614+09, was observed on January 24, 2021. We report the time-resolved spectroscopy of the burst and a burst oscillation detection at 413 Hz with a fractional amplitude 3.4\% (rms). This coincides with the burst oscillation previously discovered with \textit{Swift}/BAT \citep{Strohmayer2008}, and therefore confirms the spin frequency of this source. This burst is the brightest one in the normal bursts (except the superburst) ever detected from 4U~0614+09, which leads to an upper limit of distance estimation as 3.1 kpc. The folded light curve during the burst oscillation shows a multi-peak structure, which is the first case observed during a single burst oscillation in nonpulsating sources. The multi-peak profile could be due to additional harmonics of the burst oscillation, which is corresponding to several brighter/fainter spots at the stellar surface.
Published: 2021
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5. Search for Gamma-Ray Bursts and Gravitational Wave Electromagnetic Counterparts with High Energy X-ray Telescope of \textit{Insight}-HXMT

Author: Cai, C., Xiong, S. L., Li, C. K., Liu, C. Z., Zhang, S. N., Li, X. B., Song, L. M., Li, B., Xiao, S., Yi, Q. B., Zhu, Y., Zheng, Y. G., Chen, W., Luo, Q., Huang, Y., Song, X. Y., Zhao, H. S., Zhao, Y., Zhang, Z., Bu, Q. C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, G., Li, T. P., Li, W., Li, X., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, F. J., Lu, X. F., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L., Ren, X. Q., Sai, N., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, Y. P., Yang, R. J., Yang, S., Yang, Y. J., Yang, Y. R., Yang, X. J., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, S., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, X. F., Zheng, S. J., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The High Energy X-ray telescope (HE) on-board the Hard X-ray Modulation Telescope (\textit{Insight}-HXMT) can serve as a wide Field of View (FOV) gamma-ray monitor with high time resolution ($\mu$s) and large effective area (up to thousands cm$^2$). We developed a pipeline to search for Gamma-Ray Bursts (GRBs), using the traditional signal-to-noise ratio (SNR) method for blind search and the coherent search method for targeted search. By taking into account the location and spectrum of the burst and the detector response, the targeted coherent search is more powerful to unveil weak and sub-threshold bursts, especially those in temporal coincidence with Gravitational Wave (GW) events. Based on the original method in literature, we further improved the coherent search to filter out false triggers caused by spikes in light curves, which are commonly seen in gamma-ray instruments (e.g. \textit{Fermi}/GBM, \textit{POLAR}). We show that our improved targeted coherent search method could eliminate almost all false triggers caused by spikes. Based on the first two years of \textit{Insight}-HXMT/HE data, our targeted search recovered 40 GRBs, which were detected by either \textit{Swift}/BAT or \textit{Fermi}/GBM but too weak to be found in our blind search. With this coherent search pipeline, the GRB detection sensitivity of \textit{Insight}-HXMT/HE is increased to about 1.5E-08 erg/cm$^2$ (200 keV$-$3 MeV). We also used this targeted coherent method to search \textit{Insight}-HXMT/HE data for electromagnetic (EM) counterparts of LIGO-Virgo GW events (including O2 and O3a runs). However, we did not find any significant burst associated with GW events., Comment: 12 pages, 14 figures, 5 tables; accepted for publication in MNRAS
Published: 2021
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6. IMPROVING INDIVIDUAL CROWN BIOMASS ESTIMATION BY INCORPORATING COMPETITION FACTORS USING MIXED EFFECT MODELS FOR PINUS KESIYA

Author: Li, H, Xu, M, Leng, Y, Xu, H, Wang, J, Li, C, Wei, A, Lv, Y, Xiong, H, and Ou, G
Published: 2023

7. Accretion Torque Reversals in GRO J1008-57 Revealed by Insight-HXMT

Author: Wang, W., Tang, Y. M., Tuo, Y. L., Epili, P. R., Zhang, S. N., Song, L. M., Lu, F. J., Qu, J. L., Zhang, S., Ge, M. Y., Huang, Y., Li, B., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, C. K., Li, G., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. P., Yang, R. J., Yang, S., Yang, J. J., Yang, Y. J., Yi, B. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be about 93.28 seconds in August 2017, 93.22 seconds in February 2018, 93.25 seconds in June 2019 and 93.14 seconds in June 2020. GRO J1008-57 evolved in the spin-up process with a mean rate of $-(2.10\pm 0.05)\times$10$^{-4}$ s/d from 2009 -- 2018, and turned into a spin down process with a rate of $(6.7\pm 0.6)\times$10$^{-5}$ s/d from Feb 2018 to June 2019. During the type II outburst of 2020, GRO J1008-57 had the spin-up torque again. During the torque reversals, the pulse profiles and continuum X-ray spectra did not change significantly, and the cyclotron resonant scattering feature around 80 keV was only detected during the outbursts in 2017 and 2020. Based on the observed mean spin-up rate, we estimated the inner accretion disk radius in GRO J1008-57 (about 1 - 2 times of the Alfv\'{e}n radius) by comparing different accretion torque models of magnetic neutron stars. During the spin-down process, the magnetic torque should dominate over the matter accreting inflow torque, and we constrained the surface dipole magnetic field $B\geq 6\times 10^{12}$ G for the neutron star in GRO J1008-57, which is consistent with the magnetic field strength obtained by cyclotron line centroid energy., Comment: 10 pages, 5 figures, and 3 tables, the Journal of High Energy Astrophysics in press
Published: 2021

8. Insight-HXMT observations of Swift J0243.6+6124: the evolution of RMS pulse fractions at super-Eddington luminosity

Author: Wang, P. J., Kong, L. D., Zhang, S., Chen, Y. P., Zhang, S. N., Qu, J. L., Ji, L., Tao, L., Ge, M. Y., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, L. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yan Ji, Yang, Yi Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Zhao, Zhang, Zhi, Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., Zhu, Y., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Based on Insight-HXMT data, we report on the pulse fraction evolution during the 2017-2018 outburst of the newly discovered first Galactic ultraluminous X-ray source (ULX) Swift J0243.6+6124. The pulse fractions of 19 observation pairs selected in the rising and fading phases with similar luminosity are investigated. The results show a general trend of the pulse fraction increasing with luminosity and energy at super-critical luminosity. However, the relative strength of the pulsation between each pair evolves strongly with luminosity. The pulse fraction in the rising phase is larger at luminosity below $7.71\times10^{38}$~erg~s$^{-1}$, but smaller at above. A transition luminosity is found to be energy independent. Such a phenomena is firstly confirmed by Insight-HXMT observations and we speculate it may have relation with the radiation pressure dominated accretion disk.
Published: 2020
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9. Physical origin of the nonphysical spin evolution of MAXI J1820+070

Author: Guan, J., Tao, L., Qu, J. L., Zhang, S. N., Zhang, W., Zhang, S., Ma, R. C., Ge, M. Y., Song, L. M., Lu, F. J., Li, T. P., Xu, Y. P., Chen, Y., Cao, X. L., Liu, C. Z., Zhang, L., Wang, Y. N., Chen, Y. P., Bu, Q. C., Cai, C., Chang, Z., Chen, L., Chen, T. X., Chen, Y. B., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, 83C57
Abstract: We report on the Insight-HXMT observations of the new black hole X-ray binary MAXI J1820+070 during its 2018 outburst. Detailed spectral analysis via the continuum fitting method shows an evolution of the inferred spin during its high soft sate. Moreover, the hardness ratio, the non-thermal luminosity and the reflection fraction also undergo an evolution, exactly coincident to the period when the inferred spin transition takes place. The unphysical evolution of the spin is attributed to the evolution of the inner disc, which is caused by the collapse of a hot corona due to condensation mechanism or may be related to the deceleration of a jet-like corona. The studies of the inner disc radius and the relation between the disc luminosity and the inner disc radius suggest that, only at a particular epoch, did the inner edge of the disc reach the innermost stable circular orbit and the spin measurement is reliable. We then constrain the spin of MAXI J1820+070 to be a*=0.2^{+0.2}_{-0.3}. Such a slowly spinning black hole possessing a strong jet suggests that its jet activity is driven mainly by the accretion disc rather than by the black hole spin., Comment: 14 pages, 13 figures, 5 tables, accepted for publication in MNRAS
Published: 2020
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10. X-ray reprocessing in accreting pulsar GX 301-2 observed with Insight-HXMT

Author: Ji, L., Doroshenko, V., Suleimanov, V., Santangelo, A., Orlandini, M., Liu, J., Ducci, L., Zhang, S. N., Nabizadeh, A., Gavran, D., Zhang, S., Ge, M. Y., Li, X. B., Tao, L., Bu, Q. C., Qu, J. L., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, T. X., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. X., Liu, H. W., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Yan-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W., Zhang, W. C., Zhang, Yi, Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We investigate the absorption and emission features in observations of GX 301-2 detected with Insight-HXMT/LE in 2017-2019. At different orbital phases, we found prominent Fe Kalpha, Kbeta and Ni Kalpha lines, as well as Compton shoulders and Fe K-shell absorption edges. These features are due to the X-ray reprocessing caused by the interaction between the radiation from the source and surrounding accretion material. According to the ratio of iron lines Kalpha and Kbeta, we infer the accretion material is in a low ionisation state. We find an orbital-dependent local absorption column density, which has a large value and strong variability around the periastron. We explain its variability as a result of inhomogeneities of the accretion environment and/or instabilities of accretion processes. In addition, the variable local column density is correlated with the equivalent width of the iron Kalpha lines throughout the orbit, which suggests that the accretion material near the neutron star is spherically distributed., Comment: 10 pages, 5 figures, 2 tables, accepted for publication in MNRAS
Published: 2020
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11. Insight-HXMT observations of a possible fast transition from jet to wind dominated state during a huge flare of GRS~1915+105

Author: Kong, L. D., Zhang, S., Chen, Y. P., Zhang, S. N., Ji, L., Wang, P. J., Tao, L., Ge, M. Y., Liu, C. Z., Song, L. M., Lu, F. J., Qu, J. L., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, H. W., Liu, H. X., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, L. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, R. J., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the analysis of the brightest flare that was recorded in the \emph{Insight}-HMXT data set, in a broad energy range (2$-$200 keV) from the microquasar GRS~1915+105 during an unusual low-luminosity state. This flare was detected by \emph{Insight}-HXMT among a series of flares during 2 June 2019 UTC 16:37:06 to 20:11:36, with a 2-200 keV luminosity of 3.4$-$7.27$\times10^{38}$ erg s$^{-1}$. Basing on the broad-band spectral analysis, we find that the flare spectrum shows different behaviors during bright and faint epochs. The spectrum of the flare can be fitted with a model dominated by a power-law component. Additional components show up in the bright epoch with a hard tail and in the faint epoch with an absorption line $\sim$ 6.78 keV. The reflection component of the latter is consistent with an inner disk radius $\sim$ 5 times larger than that of the former. These results on the giant flare during the "unusual" low-luminosity state of GRS~1915+105 may suggest that the source experiences a possible fast transition from a jet-dominated state to a wind-dominated state. We speculate that the evolving accretion disk and the large-scale magnetic field may play important roles in this peculiar huge flare.
Published: 2020
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12. A variable ionized disk wind in the black-hole candidate EXO 1846-031

Author: Wang, Yanan, Ji, Long, Garcia, Javier A., Dauser, Thomas, Mendez, Mariano, Mao, Junjie, Tao, L., Altamirano, Diego, Maggi, Pierre, Zhang, S. N., Ge, M. Y., Zhang, L., Qu, J. L., Zhang, S., Ma, X., Lu, F. J., Li, T. P., Huang, Y., Zheng, S. J., Chang, Z., Tuo, Y. L., Song, L. M., Xu, Y. P., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Cao, X. L., Chen, L., Chen, T. X., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, H. W., Liu, X. J., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhao, H. S., Zhao, X. F., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: After 34 years, the black-hole candidate EXO 1846-031 went into outburst again in 2019. We investigate its spectral properties in the hard intermediate and the soft states with NuSTAR and Insight-HXMT. A reflection component has been detected in the two spectral states but possibly originating from different illumination spectra: in the intermediate state, the illuminating source is attributed to a hard coronal component, which has been commonly observed in other X-ray binaries, whereas in the soft state the reflection is probably produced by the disk self-irradiation. Both cases support EXO 1846-031 as a low inclination system of ~40 degrees. An absorption line is clearly detected at ~7.2 keV in the hard intermediate state, corresponding to a highly ionized disk wind (log {\xi} > 6.1) with a velocity up to 0.06c. Meanwhile, quasi-simultaneous radio emissions have been detected before and after the X-rays, implying the co-existence of disk winds and jets in this system. Additionally, the observed wind in this source is potentially driven by magnetic forces. The absorption line disappeared in the soft state and a narrow emission line appeared at ~6.7 keV on top of the reflection component, which may be evidence for disk winds, but data with the higher spectral resolution are required to examine this., Comment: Accepted for publication in ApJ
Published: 2020
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13. Constraining the transient high-energy activity of FRB180916.J0158+65 with Insight-HXMT followup observations

Author: Guidorzi, C., Orlandini, M., Frontera, F., Nicastro, L., Xiong, S. L., Liao, J. Y., Li, G., Zhang, S. N., Amati, L., Virgilli, E., Zhang, S., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, L., Chen, T. X., Chen, Y., Chen, Y. P., Cui, W. W., Du, Y. Y., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Z. W., Liang, X. H., Liu, B. S., Liu, C. Z., Liu, H. X., Liu, H. W., Liu, X. J., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Ma, R. C., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L, Ren, X. Q., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, L. J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xu, Y. P., Yang, R., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, W. C., Zhang, W., Zhang, Y. F., Zhang, Y. H., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., and Zhou, D. K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: A link between magnetars and fast radio burst (FRB) sources has finally been established. In this context, one of the open issues is whether/which sources of extra galactic FRBs exhibit X/gamma-ray outbursts and whether it is correlated with radio activity. We aim to constrain possible X/gamma-ray burst activity from one of the nearest extragalactic FRB sources currently known over a broad energy range, by looking for bursts over a range of timescales and energies that are compatible with being powerful flares from extragalactic magnetars. We followed up the as-yet nearest extragalactic FRB source at a mere 149 Mpc distance, the periodic repeater FRB180916.J0158+65, during the active phase on February 4-7, 2020, with the Insight-Hard X-ray Modulation Telescope (HXMT). Taking advantage of the combination of broad band, large effective area, and several independent detectors available, we searched for bursts over a set of timescales from 1 ms to 1.024 s with a sensitive algorithm, that had previously been characterised and optimised. Moreover, through simulations we studied the sensitivity of our technique in the released energy-duration phase space for a set of synthetic flares and assuming different energy spectra. We constrain the possible occurrence of flares in the 1-100 keV energy band to E<10^46 erg for durations <0.1 s over several tens of ks exposure. We can rule out the occurrence of giant flares similar to the ones that were observed in the few cases of Galactic magnetars. The absence of reported radio activity during our observations does not allow us to make any statements on the possible simultaneous high-energy emission., Comment: 10 pages, 3 figures, accepted by A&A
Published: 2020
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14. Insight-HXMT firm detection of the highest energy fundamental cyclotron resonance scattering feature in the spectrum of GRO J1008-57

Author: Ge, M. Y., Ji, L., Zhang, S. N., Santangelo, A., Liu, C. Z., Doroshenko, V., Staubert, R., Qu, J. L., Zhang, S., Lu, F. J., Song, L. M., Li, T. P., Tao, L., Xu, Y. P., Cao, X. L., Chen, Y., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, L. J., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on the observation of the accreting pulsar GRO J1008-57 performed by Insight-HXMT at the peak of the source's 2017 outburst. Pulsations are detected with a spin period of 93.283(1) s. The pulse profile shows double peaks at soft X-rays, and only one peak above 20 keV. The spectrum is well described by the phenomenological models of X-ray pulsars. A cyclotron resonant scattering feature is detected with very high statistical significance at a centroid energy of $E_{\rm cyc}=90.32_{-0.28}^{+0.32}$ keV, for the reference continuum and line models, HIGHECUT and GABS respectively. Detection is very robust with respect to different continuum models. The line energy is significantly higher than what suggested from previous observations, which provided very marginal evidence for the line. This establishes a new record for the centroid energy of a fundamental cyclotron resonant scattering feature observed in accreting pulsars. We also discuss the accretion regime of the source during the Insight-HXMT observation., Comment: 8 pages, 3 figures, accepted for publication in ApJL
Published: 2020
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15. HXMT Identification of a non-thermal X-ray burst from SGR J1935+2154 and with FRB 200428

Author: Li, C. K., Lin, L., Xiong, S. L., Ge, M. Y., Li, X. B., Li, T. P., Lu, F. J., Zhang, S. N., Tuo, Y. L., Nang, Y., Zhang, B., Xiao, S., Chen, Y., Song, L. M., Xu, Y. P., Liu, C. Z., Jia, S. M., Cao, X. L., Qu, J. L., Zhang, S., Gu, Y. D., Liao, J. Y., Zhao, X. F., Tan, Y., Nie, J. Y., Zhao, H. S., Zheng, S. J., Zheng, Y. G., Luo, Q., Cai, C., Li, B., Xue, W. C., Bu, Q. C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Yue, Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Zhi, Zhang, Z. L., Zhou, D. K., Zhou, J. F., Zhu, Y., Zhu, Y. X., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Fast radio bursts (FRBs) are short pulses observed in radio band from cosmological distances. One class of models invoke soft gamma-ray repeaters (SGRs), or magnetars, as the sources of FRBs. Some radio pulses have been observed from some magnetars, however, no FRB-like events had been detected in association any magnetar burst, including one giant flare. Recently, a pair of FRB-like bursts (FRB 200428 hereafter) separated by milliseconds (ms) were detected from the general direction of the Galactic magnetar SGR J1935+2154. Here we report the detection of a non-thermal X-ray burst in the 1-250 keV energy band with the Insight-HXMT satellite, which we identify as emitted from SGR J1935+2154. The burst showed two hard peaks with a separation of 34 ms, broadly consistent with that of the two bursts in FRB 200428. The delay time between the double radio and X-ray peaks is about 8.57 s, fully consistent with the dispersion delay of FRB 200428. We thus identify the non-thermal X-ray burst is associated with FRB 200428 whose high energy counterpart is the two hard peaks in X-ray. Our results suggest that the non-thermal X-ray burst and FRB 200428 share the same physical origin in an explosive event from SGR J1935+2154., Comment: 24 pages, 9 figures, 6 tables; initial submission to a journal on May 9th, 2020. Significant changes include updated localization and detailed spectral evolution of the X-ray burst, and better determination of the two narrow X-ray peaks corresponding to the two radio pulses. Conclusions are strengthened. Nature Astronomy online on Feb. 18, 2021
Published: 2020
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16. Insight-HXMT insight into switch of the accretion mode: the case of the X-ray pulsar 4U 1901+03

Author: Tuo, Y. L., Ji, L., Tsygankov, S. S., Mihara, T., Song, L. M., Ge, M. Y., Nabizadeh, A., Tao, L., Qu, J. L., Zhang, Y., Zhang, S., Zhang, S. N., Bu, Q. C., Chen, L., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., Zhu, Y., and Zhuang, R. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We use the In data collected during the 2019 outburst from X-ray pulsar 4U 1901+03 to complement the orbital parameters reported by Fermi/GBM. Using the Insight-HXMT, we examine the correlation between the derivative of the intrinsic spin frequency and bolometric flux based on accretion torque models. It was found that the pulse profiles significantly evolve during the outburst. The existence of two types of the profile's pattern discovered in the Insight-HXMT data indicates that this source experienced transition between a super-critical and a sub-critical accretion regime during its 2019 outburst. Based on the evolution of the pulse profiles and the torque model, we derive the distance to 4U 1901+03 as 12.4+-0.2 kpc., Comment: 8 pages, 5 figures, accepted by JHEAP
Published: 2020

17. The evolution of the broadband temporal features observed in the black-hole transient MAXI J1820+070 with Insight-HXMT

Author: Wang, Yanan, Ji, Long, Zhang, S. N., Méndez, Mariano, Qu, J. L., Maggi, Pierre, Ge, M. Y., Qiao, Erlin, Tao, L., Zhang, S., Altamirano, Diego, Zhang, L., Ma, X., Lu, F. J., Li, T. P., Huang, Y., Zheng, S. J., Chen, Y. P., Chang, Z., Tuo, Y. L., Gungor, C., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zhou, D. K., Zhou, J. F., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We study the evolution of the temporal properties of MAXI 1820+070 during the 2018 outburst in its hard state from MJD 58190 to 58289 with Insight-HXMT in a broad energy band 1-150 keV. We find different behaviors of the hardness ratio, the fractional rms and time lag before and after MJD 58257, suggesting a transition occurred at around this point. The observed time lags between the soft photons in the 1-5 keV band and the hard photons in higher energy bands, up to 150 keV, are frequency-dependent: the time lags in the low-frequency range, 2-10 mHz, are both soft and hard lags with a timescale of dozens of seconds but without a clear trend along the outburst; the time lags in the high-frequency range, 1-10 Hz, are only hard lags with a timescale of tens of milliseconds; first increase until around MJD 58257 and decrease after this date. The high-frequency time lags are significantly correlated to the photon index derived from the fit to the quasi-simultaneous NICER spectrum in the 1-10 keV band. This result is qualitatively consistent with a model in which the high-frequency time lags are produced by Comptonization in a jet., Comment: Accepted for publication in ApJ
Published: 2020
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18. Discovery of delayed spin-up behavior following two large glitches in the Crab pulsar, and the statistics of such processes

Author: Ge, M. Y., Zhang, S. N., Lu, F. J., Li, T. P., Yuan, J. P., Zheng, X. P., Huang, Y., Zheng, S. J., Chen, Y. P., Chang, Z., Tuo, Y. L., Cheng, Q., Güngör, C., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Zhang, S., Qu, J. L., Bu, Q. C., Cai, C., Chen, G., Chen, L., Chen, M. Z., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hao, L. F., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, C. J., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, D., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Li, Z. X., Liu, Z. Y., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tan, Y., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, J. B., Wang, M., Wang, N., Wang, W. S., Wang, Y. D., Wang, Y. S., Wen, X. Y., Wen, Z. G., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. H., Yan, W. M., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., Yin, Q. Q., You, Y., Yue, Y. L., Zhang, A. M., Zhang, C. M., Zhang, D. P., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, W., Zhou, D. K., Zhou, J. F., Zhou, X., Zhuang, R. L., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Glitches correspond to sudden jumps of rotation frequency ($\nu$) and its derivative ($\dot{\nu}$) of pulsars, the origin of which remains not well understood yet, partly because the jump processes of most glitches are not well time-resolved. There are three large glitches of the Crab pulsar, detected in 1989, 1996 and 2017, which were found to have delayed spin-up processes before the normal recovery processes. Here we report two additional glitches of the Crab pulsar occurred in 2004 and 2011 for which we discovered delayed spin up processes, and present refined parameters of the largest glitch occurred in 2017. The initial rising time of the glitch is determined as $<0.48$ hour. We also carried out a statistical study of these five glitches with observed spin-up processes. The two glitches occurred in 2004 and 2011 have delayed spin-up time scales ($\tau_{1}$) of $1.7\pm0.8$\,days and $1.6\pm0.4$\,days, respectively. We find that the $\Delta{\nu}$ vs. $|\Delta{\dot\nu}|$ relation of these five glitches is similar to those with no detected delayed spin-up process, indicating that they are similar to the others in nature except that they have larger amplitudes. For these five glitches, the amplitudes of the delayed spin-up process ($|\Delta{\nu}_{\rm d1}|$) and recovery process ($\Delta{\nu}_{\rm d2}$), their time scales ($\tau_{1}$, $\tau_{2}$), and permanent changes in spin frequency ($\Delta{\nu}_{\rm p}$) and total frequency step ($\Delta{\nu}_{\rm g}$) have positive correlations. From these correlations, we suggest that the delayed spin-up processes are common for all glitches, but are too short and thus difficult to be detected for most glitches., Comment: 25 pages, 8 figures
Published: 2020
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19. Switches between accretion structures during flares in 4U 1901+03

Author: Ji, L., Ducci, L., Santangelo, A., Zhang, S., Suleimanov, V., Tsygankov, S., Doroshenko, V., Nabizadeh, A., Zhang, S. N., Ge, M. Y., Tao, L., Bu, Q. C., Qu, J. L., Lu, F. J., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. X., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yan-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Yi, Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Yue, Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on our analysis of the 2019 outburst of the X-ray accreting pulsar 4U 1901+03 observed with Insight-HXMT and NICER. Both spectra and pulse profiles evolve significantly in the decaying phase of the outburst. Dozens of flares are observed throughout the outburst. They are more frequent and brighter at the outburst peak. We find that the flares, which have a duration from tens to hundreds of seconds, are generally brighter than the persistent emission by a factor of $\sim$ 1.5. The pulse profile shape during the flares can be significantly different than that of the persistent emission. In particular, a phase shift is clearly observed in many cases. We interpret these findings as direct evidence of changes of the pulsed beam pattern, due to transitions between the sub- and super-critical accretion regimes on a short time scale. We also observe that at comparable luminosities the flares' pulse profiles are rather similar to those of the persistent emission. This indicates that the accretion on the polar cap of the neutron star is mainly determined by the luminosity, i.e., the mass accretion rate., Comment: 11 pages, 8 figures, accepted for publication in MNRAS
Published: 2020
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20. Joint Analysis of Energy and RMS Spectra from MAXI J1535-571 with Insight-HXMT

Author: Kong, L. D., Zhang, S., Chen, Y. P., Ji, L., Zhang, S. N., Yang, Y. R., Tao, L., Ma, X., Qu, J. L., Lu, F. J., Bu, Q. C., Chen, L., Song, L. M., Li, T. P., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. X., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Ren, X. Q., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, P. J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yi, Q. B., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, P., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Y. H., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zheng, Y. G., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: A new black hole X-ray binary (BHXRB) MAXI J1535-571 was discovered by MAXI during its outburst in 2017. Using observations taken by the first Chinese X-ray satellite, the Hard X-ray Modulation Telescope (dubbed as Insight-HXMT), we perform a joint spectral analysis (2-150 keV) in both energy and time domains. The energy spectra provide the essential input for probing the intrinsic Quasi-Periodic Oscillation (QPO) fractional rms spectra (FRS). Our results show that during the intermediate state, the energy spectra are in general consistent with those reported by Swift/XRT and NuSTAR. However, the QPO FRS become harder and the FRS residuals may suggest the presence of either an additional power-law component in the energy spectrum or a turn-over in the intrinsic QPO FRS at high energies.
Published: 2020

21. Diagnostic of the spectral properties of Aquila X-1 by Insight-HXMT snapshots during the early propeller phase

Author: Güngör, C., Ge, M. Y., Zhang, S., Santangelo, A., Zhang, S. N., Lu, F. J., Zhang, Y., Chen, Y. P., Tao, L., Yang, Y. J., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Ji, L., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Luo, Q., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Xu, Y. P., Yang, J. W., Yang, S., Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We study the 2018 outburst of Aql X-1 via the monitor of all sky X-ray image (MAXI) data. We show that the outburst starting in February 2018 is a member of short-low class in the frame of outburst duration and the peak count rate although the outburst morphology is slightly different from the other fast-rise-exponential-decay (FRED) type outbursts with a milder rising stage. We study the partial accretion in the weak propeller stage of Aql X-1 via the MAXI data of the 2018 outburst. We report on the spectral analysis of 3 observations of Aquila X-1 obtained by Insight - hard X-ray modulation telescope (Insight-HXMT) during the late decay stage of the 2018 outburst. We discuss that the data taken by Insight-HXMT is just after the transition to the weak propeller stage. Our analysis shows the necessity of a comptonization component to take into account the existence of an electron cloud resulting photons partly up-scattered., Comment: 8 pages, 4 figures, accepted for publication in JHEAp
Published: 2019

22. $Insight$-HXMT Science Operations

Author: Jia, S. M., Ma, X., Huang, Y., Zhang, W. Z., Ou, G., Song, L. M., Qu, J. L., Zhang, S., and Chen, L.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Phenomenology
Abstract: The Hard X-ray Modulation Telescope ($Insight$-HXMT) was successfully launched on June 15th, 2017. It performs broad band X-ray scan survey of the Galactic Plane to detect new black holes and other objects in active states. It also observes X-ray binaries to study their X-ray variabilities. Here we will introduce the Science Operations of $Insight$-HXMT, which is responsible for collecting and evaluating observation proposals, scheduling observations, and monitoring the working status of the payloads.
Published: 2019
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23. $Insight$-HXMT study of the timing properties of Sco X-1

Author: Jia, S. M., Bu, Q. C., Qu, J. L., Lu, F. J., Zhang, S. N., Huang, Y., Ma, X., Tao, L., Xiao, G. C., Zhang, W., Chen, L., Song, L. M., Zhang, S., Li, T. B., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Cai, C., Chang, Z., Chen, G., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, X. Y., Sun, L., Tan, Y., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yin, Q. Q., Yi, Q. B., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y. X., and Zhu, Y.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: 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 ($Insight$-HXMT) from July 2017 to August 2018. A complete $Z$-track hardness-intensity diagram (HID) is obtained. The normal branch oscillations (NBOs) at $\sim$ 6 Hz in the lower part of the normal branch (NB) and the flare branch oscillations (FBOs) at $\sim$ 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 $Insight$-HXMT, while the horizontal branch oscillations (HBOs) at $\sim$ 40 Hz and the kilohertz quasi-periodic oscillations (kHz QPOs) at $\sim$ 800 Hz are found simultaneously up to 60 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 $\sim$ 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.
Published: 2019

24. Insight-HXMT observation on 4U~1608--52: evolving spectral properties of a bright type-I X-ray burst

Author: Chen, Y. P., Zhang, S., Zhang, S. N., Ji, L., Kong, L. D., Santangelo, A., Qu, J. L., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Bu, Q. C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, J. Y. Liao G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiao, S., Xiong, S. L., Yang, J. W., Yang, S., Yang, Yang-Ji, Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W., Zhang, W. Z., Zhang, Yi., Zhang, Y. F., Zhang, Y. J., Zhang, Yue., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, D. K., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: 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 $\sim$ 40 percentages. We speculate that the enhanced emission is from a region beyond the PRE radius, or through the Comptonization of the corona., Comment: accepted by JHEA(Journal of High Energy Astrophysics)
Published: 2019

25. Insight-HXMT observations of 4U~1636-536: Corona cooling revealed with single short type-I X-ray burst

Author: Chen, Y. P., Zhang, S., Zhang, S. N., Ji, L., Kong, L. D., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Qu, J. L., Sai, N., Song, L. M., Sun, L., Tan, Y., Tao, L., Tao, W. H., Tuo, Y. L., Wang, G. F., Wang, H. Y., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., hang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Corona cooling was detected previously from stacking a series of short type-I bursts occurred during the low/had state of atoll outburst. Type-I bursts are hence regarded as sharp probe to our better understanding on the basic property of the corona. The launch of the first Chinese X-ray satellite Insight-HXMT has large detection area at hard X-rays which provide almost unique chance to move further in this research field. We report the first detection of the corona cooling by Insight-HXMT from single short type-I burst showing up during {\bf flare} of 4U 1636-536. This type-I X-ray burst has a duration of $\sim$13 seconds and hard X-ray shortage is detected with significance 6.2~$\sigma$ in 40-70 keV. A cross-correlation analysis between the lightcurves of soft and hard X-ray band, shows that the corona shortage lag the burst emission by 1.6 $\pm$1.2~s. These results are consistent with those derived previously from stacking a large amount of bursts detected by RXTE/PCA within a series of {\bf flares} of 4U 1636-536. Moreover, the broad bandwidth of Insight-HXMT allows as well for the first time to infer the burst influence upon the continuum spectrum via performing the spectral fitting of the burst, which ends up with the finding that hard X-ray shortage appears at around 40 keV in the continuum spectrum. These results suggest that the evolution of the corona along with the outburst{\bf /flare} of NS XRB may be traced via looking into a series of embedded type-I bursts by using Insight-HXMT., Comment: published in 2018, ApJL,864, L30
Published: 2019
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26. Timing analysis of 2S 1417-624 observed with NICER and Insight-HXMT

Author: Ji, L., Doroshenko, V., Santangelo, A., Gungor, C., Zhang, S., Ducci, L., Zhang, S. -N., Ge, M. -Y., Qu, L. J., Chen, Y. P., Bu, Q. C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yang, Y. R., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a study of timing properties of the accreting pulsar 2S 1417-624 observed during its 2018 outburst, based on Swift/BAT, Fermi/GBM, Insight-HXMT and NICER observations. We report a dramatic change of the pulse profiles with luminosity. The morphology of the profile in the range 0.2-10.0keV switches from double to triple peaks at $\sim2.5$ $\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$ and from triple to quadruple peaks at $\sim7$ $\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$. The profile at high energies (25-100keV) shows significant evolutions as well. We explain this phenomenon according to existing theoretical models. We argue that the first change is related to the transition from the sub to the super-critical accretion regime, while the second to the transition of the accretion disc from the gas-dominated to the radiation pressure-dominated state. Considering the spin-up as well due to the accretion torque, this interpretation allows to estimate the magnetic field self-consistently at $\sim7\times 10^{12}$G., Comment: 7 pages, 4 figures, 1 tables, accepted for publication in MNRAS
Published: 2019
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27. Constant cyclotron line energy in Hercules X-1 -- Joint Insight-HXMT and NuSTAR observations

Author: Xiao, G. C., Ji, L., Staubert, R., Ge, M. Y., Zhang, S., Zhang, S. N., Santangelo, A., Ducci, L., Liao, J. Y., Guo, C. C., Li, X. B., Zhang, W., Qu, J. L., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Bu, Q. C., Cai, C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Gungor, C., Han, D. W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, S. X., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiong, S. L., Yang, J. W., Yang, S., Yang, Y. J., Yin, Q. B., Yin, Q. Q., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, X. F., Zheng, S. J., Zhou, J. F., Zhu, Y., and Zhu, Y. X.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The long-term evolution of the centroid energy of the CRSF in Her X-1 is still a mystery. We report a new measurement from a campaign between {\sl Insight}-HXMT and {\sl NuSTAR} performed in February 2018. Generally, the two satellites show well consistent results of timing and spectral properties. The joint spectral analysis confirms that the previously observed long decay phase has ended, and that the line energy instead keeps constant around 37.5 keV after flux correction.
Published: 2019

28. Hot disk of the Swift J0243.6+6124 revealed by Insight-HXMT

Author: Doroshenko, V., Zhang, S. N., Santangelo, A., Ji, L., Tsygankov, S., Mushtukov, A., Qu, L. J., Zhang, S., Ge, M. Y., Chen, Y. P., Bu, Q. C., Cao, X. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, Guo, C. C., Han, D. W., Hu, W., Huang, Y., Huo, J., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, B., Li, C. K., Li, G., Li, M. S., Li, T. P., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, C. Z., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, F. J., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G., Sai, N., Song, L. M., Song, X. Y., Sun, L., Tan, Y., Tao, L., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Xu, Y. P., Yang, Y. R., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on analysis of observations of the bright transient X-ray pulsar \src obtained during its 2017-2018 giant outburst with Insight-HXMT, \emph{NuSTAR}, and \textit{Swift} observatories. We focus on the discovery of a sharp state transition of the timing and spectral properties of the source at super-Eddington accretion rates, which we associate with the transition of the accretion disk to a radiation pressure dominated (RPD) state, the first ever directly observed for magnetized neutron star. This transition occurs at slightly higher luminosity compared to already reported transition of the source from sub- to super-critical accretion regime associate with onset of an accretion column. We argue that this scenario can only be realized for comparatively weakly magnetized neutron star, not dissimilar to other ultra-luminous X-ray pulsars (ULPs), which accrete at similar rates. Further evidence for this conclusion is provided by the non-detection of the transition to the propeller state in quiescence which strongly implies compact magnetosphere and thus rules out magnetar-like fields., Comment: Submitted to MNRAS
Published: 2019
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29. In-orbit demonstration of X-ray pulsar navigation with the Insight-HXMT satellite

Author: Zheng, S. J., Zhang, S. N., Lu, F. J., Wang, W. B., Gao, Y., Li, T. P., Song, L. M., Ge, M. Y., Han, D. W., Chen, Y., Xu, Y. P., Cao, X. L., Liu, C. Z., Zhang, S., Qu, J. L., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Gungor, C., Guo, C. C., Hu, W., Huang, Y., Huo, J., Ji, J. F., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G, Sai, N., Shang, R. C., Sun, L., Tan, Y., Tao, L., Tao, W., Tuo, Y. L., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: In this work, we report the in-orbit demonstration of X-ray pulsar navigation with Insight-Hard X-ray Modulation Telescope (Insight-HXMT), which was launched on Jun. 15th, 2017. The new pulsar navigation method 'Significance Enhancement of Pulse-profile with Orbit-dynamics' (SEPO) is adopted to determine the orbit with observations of only one pulsar. In this test, the Crab pulsar is chosen and observed by Insight-HXMT from Aug. 31th to Sept. 5th in 2017. Using the 5-day-long observation data, the orbit of Insight-HXMT is determined successfully with the three telescopes onboard - High Energy X-ray Telescope (HE), Medium Energy X-ray Telescope (ME) and Low Energy X-ray Telescope (LE) - respectively. Combining all the data, the position and velocity of the Insight-HXMT are pinpointed to within 10 km (3 sigma) and 10 m/s (3 sigma), respectively., Comment: Accepted by the Astrophysical Journal Supplement
Published: 2019
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30. Insight-HXMT observations of the New Black Hole Candidate MAXI J1535-571: timing analysis

Author: Huang, Y., Qu, J. L., Zhang, S. N., Bu, Q. C., Chen, Y. P., Tao, L., Zhang, S., Lu, F. J., Li, T. P., Song, L. M., Xu, Y. P., Cao, X. L., Chen, Y., Liu, C. Z., Chang, H. -K., Yu, W. f., Weng, S. S., Hou, X., Kong, A. K. H., Xie, F. G., Zhang, G. B., ZHOU, J. F., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Ge, M. Y., Gu, Y. D., Guan, J., Gungor, C., Guo, C. C., Han, D. W., Hu, W., Huo, J., Ji, J. F., Jia, S. M., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Li, B., Li, C. K., Li, G., Li, M. S., Li, W., Li, X., Li, X. B., Li, X. F., Li, Y. G., Li, Z. J., Li, Z. W., Liang, X. H., Liao, J. Y., Liu, G. Q., Liu, H. W., Liu, S. Z., Liu, X. J., Liu, Y., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J. Y., Ou, G, Sai, N., Shang, R. C., Sun, L., Tan, Y., Tao, W., Tuo, Y. L., Wang, G. F., Wang, H. Y., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, M., Xiao, G. C., Xiong, S. L., Xu, H., Yan, L. L., Yang, J. W., Yang, S., Yang, Y. J., Zhang, A. M., Zhang, C. L., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, Q., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Z. L., Zhao, H. S., Zhao, J. L., Zhao, X. F., Zheng, S. J., Zhu, Y., Zhu, Y. X., and Zou, C. L.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the X-ray timing results of the new black hole candidate (BHC) MAXI J1535-571 during its 2017 outburst from Hard X-ray Modulation Telescope (\emph{Insight}-HXMT) observations taken from 2017 September 6 to 23. Following the definitions given by \citet{Belloni2010}, we find that the source exhibits state transitions from Low/Hard state (LHS) to Hard Intermediate state (HIMS) and eventually to Soft Intermediate state (SIMS). Quasi-periodic oscillations (QPOs) are found in the intermediate states, which suggest different types of QPOs. With the large effective area of \emph{Insight}-HXMT at high energies, we are able to present the energy dependence of the QPO amplitude and centroid frequency up to 100 keV which is rarely explored by previous satellites. We also find that the phase lag at the type-C QPOs centroid frequency is negative (soft lags) and strongly correlated with the centroid frequency. By assuming a geometrical origin of type-C QPOs, the source is consistent with being a high inclination system., Comment: 12 pages, 11 figures, Sumbitted to ApJ
Published: 2018
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31. Theoretical Modeling and Evaluation of Thermal Stress Evolution of Concrete at Early Age by Temperature Stress Testing Machine

Author: Ou, G. F., Kishi, T., Lin, Z. H., Kamada, T., di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Dao, Vinh, editor, and Kitipornchai, Sritawat, editor
Published: 2021
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32. α5β1-Integrin promotes tension-dependent mammary epithelial cell invasion by engaging the fibronectin synergy site.

Author: Miroshnikova, YA, Rozenberg, GI, Cassereau, L, Pickup, M, Mouw, JK, Ou, G, Templeman, KL, Hannachi, E-I, Gooch, KJ, Sarang-Sieminski, AL, García, AJ, and Weaver, VM
Subjects: Breast, Cells, Cultured, Cell Membrane, Extracellular Matrix, Epithelial Cells, Animals, Mice, Transgenic, Humans, Mice, Neoplasms, Fibronectins, Integrin alpha5beta1, Integrins, Cytokines, Cell Adhesion, Signal Transduction, Female, Phosphatidylinositol 3-Kinases, Heterografts, Cells, Cultured, Transgenic, Biological Sciences, Medical and Health Sciences, Developmental Biology
Abstract: Tumors are fibrotic and characterized by abundant, remodeled, and cross-linked collagen that stiffens the extracellular matrix stroma. The stiffened collagenous stroma fosters malignant transformation of the tissue by increasing tumor cell tension to promote focal adhesion formation and potentiate growth factor receptor signaling through kinase. Importantly, collagen cross-linking requires fibronectin (FN). Fibrotic tumors contain abundant FN, and tumor cells frequently up-regulate the FN receptor α5β1 integrin. Using transgenic and xenograft models and tunable two- and three-dimensional substrates, we show that FN-bound α5β1 integrin promotes tension-dependent malignant transformation through engagement of the synergy site that enhances integrin adhesion force. We determined that ligation of the synergy site of FN permits tumor cells to engage a zyxin-stabilized, vinculin-linked scaffold that facilitates nucleation of phosphatidylinositol (3,4,5)-triphosphate at the plasma membrane to enhance phosphoinositide 3-kinase (PI3K)-dependent tumor cell invasion. The data explain why rigid collagen fibrils potentiate PI3K activation to promote malignancy and offer a perspective regarding the consistent up-regulation of α5β1 integrin and FN in many tumors and their correlation with cancer aggression.
Published: 2017

33. HXMT identification of a non-thermal X-ray burst from SGR J1935+2154 and with FRB 200428

Author: Li, C. K., Lin, L., Xiong, S. L., Ge, M. Y., Li, X. B., Li, T. P., Lu, F. J., Zhang, S. N., Tuo, Y. L., Nang, Y., Zhang, B., Xiao, S., Chen, Y., Song, L. M., Xu, Y. P., Liu, C. Z., Jia, S. M., Cao, X. L., Qu, J. L., Zhang, S., Gu, Y. D., Liao, J. Y., Zhao, X. F., Tan, Y., Nie, J. Y., Zhao, H. S., Zheng, S. J., Zheng, Y. G., Luo, Q., Cai, C., Li, B., Xue, W. C., Bu, Q. C., Chang, Z., Chen, G., Chen, L., Chen, T. X., Chen, Y. B., Chen, Y. P., Cui, W., Cui, W. W., Deng, J. K., Dong, Y. W., Du, Y. Y., Fu, M. X., Gao, G. H., Gao, H., Gao, M., Gu, Y. D., Guan, J., Guo, C. C., Han, D. W., Huang, Y., Huo, J., Jiang, L. H., Jiang, W. C., Jin, J., Jin, Y. J., Kong, L. D., Li, G., Li, M. S., Li, W., Li, X., Li, X. F., Li, Y. G., Li, Z. W., Liang, X. H., Liu, B. S., Liu, G. Q., Liu, H. W., Liu, X. J., Liu, Y. N., Lu, B., Lu, X. F., Luo, T., Ma, X., Meng, B., Ou, G., Sai, N., Shang, R. C., Song, X. Y., Sun, L., Tao, L., Wang, C., Wang, G. F., Wang, J., Wang, W. S., Wang, Y. S., Wen, X. Y., Wu, B. B., Wu, B. Y., Wu, M., Xiao, G. C., Xu, H., Yang, J. W., Yang, S., Yang, Y. J., Yang, Yi-Jung, Yi, Q. B., Yin, Q. Q., You, Y., Zhang, A. M., Zhang, C. M., Zhang, F., Zhang, H. M., Zhang, J., Zhang, T., Zhang, W., Zhang, W. C., Zhang, W. Z., Zhang, Y., Zhang, Yue, Zhang, Y. F., Zhang, Y. J., Zhang, Z., Zhang, Zhi, Zhang, Z. L., Zhou, D. K., Zhou, J. F., Zhu, Y., Zhu, Y. X., and Zhuang, R. L.
Published: 2021
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34. Insight-HXMT insight into switch of the accretion mode: The case of the X-ray pulsar 4U 1901+03

Author: Tuo, Y.L., Ji, L., Tsygankov, S.S., Mihara, T., Song, L.M., Ge, M.Y., Nabizadeh, A., Tao, L., Qu, J.L., Zhang, Y., Zhang, S., Zhang, S.N., Bu, Q.C., Chen, L., Xu, Y.P., Cao, X.L., Chen, Y., Liu, C.Z., Cai, C., Chang, Z., Chen, G., Chen, T.X., Chen, Y.B., Chen, Y.P., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Gu, Y.D., Guan, J., Guo, C.C., Han, D.W., Huang, Y., Huo, J., Jia, S.M., Jiang, L.H., Jiang, W.C., Jin, J., Jin, Y.J., Kong, L.D., Li, B., Li, C.K., Li, G., Li, M.S., Li, T.P., Li, W., Li, X., Li, X.B., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liao, J.Y., Liu, B.S., Liu, G.Q., Liu, H.W., Liu, X.J., Liu, Y.N., Lu, B., Lu, F.J., Lu, X.F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Sai, N., Shang, R.C., Song, X.Y., Sun, L., Tan, Y., Wang, C., Wang, G.F., Wang, J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.Y., Wu, B.B., Wu, M., Xiao, G.C., Xiao, S., Xiong, S.L., Yang, J.W., Yang, S., Yang, Y.J., Yi, Q.B., Yin, Q.Q., You, Y., Zhang, A.M., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, T., Zhang, W., Zhang, W.C., Zhang, W.Z., Zhang, Y.F., Zhang, Y.J., Zhang, Y.H., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zheng, Y.G., Zhou, D.K., Zhou, J.F., Zhu, Y.X., Zhu, Y., and Zhuang, R.L.
Published: 2020
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35. Joint analysis of energy and RMS spectra from MAXI J1535-571 with Insight-HXMT

Author: Kong, L.D., Zhang, S., Chen, Y.P., Ji, L., Zhang, S.N., Yang, Y.R., Tao, L., Ma, X., Qu, J.L., Lu, F.J., Bu, Q.C., Chen, L., Song, L.M., Li, T.P., Xu, Y.P., Cao, X.L., Chen, Y., Liu, C.Z., Cai, C., Chang, Z., Chen, G., Chen, T.X., Chen, Y.B., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Ge, M.Y., Gu, Y.D., Guan, J., Guo, C.C., Han, D.W., Huang, Y., Huo, J., Jia, S.M., Jiang, L.H., Jiang, W.C., Jin, J., Li, B., Li, C.K., Li, G., Li, M.S., Li, W., Li, X., Li, X.B., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liao, J.Y., Liu, G.Q., Liu, H.X., Liu, H.W., Liu, S.Z., Liu, X.J., Liu, Y.N., Lu, B., Lu, X.F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Ren, X.Q., Sai, N., Song, X.Y., Sun, L., Tan, Y., Tuo, Y.L., Wang, C., Wang, G.F., Wang, J., Wang, P.J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.Y., Wu, B.B., Wu, M., Xiao, G.C., Xiao, S., Xiong, S.L., Xu, H., Yang, J.W., Yang, S., Yang, Y.J., Yi, Q.B., You, Y., Zhang, A.M., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, P., Zhang, T., Zhang, W., Zhang, W.C., Zhang, W.Z., Zhang, Y., Zhang, Y.F., Zhang, Y.J., Zhang, Y.H., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zheng, Y.G., Zhou, D.K., Zhou, J.F., Zhu, Y.X., and Zhu, Y.
Published: 2020
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36. Diagnostic of the spectral properties of Aquila X-1 by Insight-HXMT snapshots during the early propeller phase

Author: Güngör, C., Ge, M.Y., Zhang, S., Santangelo, A., Zhang, S.N., Lu, F.J., Zhang, Y., Chen, Y.P., Tao, L., Yang, Y.J., Bu, Q.C., Cai, C., Cao, X.L., Chang, Z., Chen, G., Chen, L., Chen, T.X., Chen, Y., Chen, Y.B., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Gu, Y.D., Guan, J., Guo, C.C., Han, D.W., Huang, Y., Huo, J., Ji, L., Jia, S.M., Jiang, L.H., Jiang, W.C., Jin, J., Kong, L.D., Li, B., Li, C.K., Li, G., Li, M.S., Li, T.P., Li, W., Li, X., Li, X.B., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liao, J.Y., Liu, C.Z., Liu, G.Q., Liu, H.W., Liu, X.J., Liu, Y.N., Lu, B., Lu, X.F., Luo, T., Luo, Q., Ma, X., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Sai, N., Song, L.M., Song, X.Y., Sun, L., Tan, Y., Tuo, Y.L., Wang, C., Wang, G.F., Wang, J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.B., Wu, B.Y., Wu, M., Xiao, G.C., Xiao, S., Xiong, S.L., Xu, Y.P., Yang, J.W., Yang, S., Yi, Q.B., Yin, Q.Q., You, Y., Zhang, A.M., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, T., Zhang, W., Zhang, W.C., Zhang, W.Z., Zhang, Y.F., Zhang, Y.J., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zhou, D.K., Zhou, J.F., Zhu, Y., and Zhu, Y.X.
Published: 2020
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37. Insight-HXMT study of the timing properties of Sco X-1

Author: Jia, S.M., Bu, Q.C., Qu, J.L., Lu, F.J., Zhang, S.N., Huang, Y., Ma, X., Tao, L., Xiao, G.C., Zhang, W., Chen, L., Song, L.M., Zhang, S., Li, T.P., Xu, Y.P., Cao, X.L., Chen, Y., Liu, C.Z., Cai, C., Chang, Z., Chen, G., Chen, T.X., Chen, Y.B., Chen, Y.P., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Ge, M.Y., Gu, Y.D., Guan, J., Guo, C.C., Han, D.W., Huo, J., Jiang, L.H., Jiang, W.C., Jin, J., Jin, Y.J., Kong, L.D., Li, B., Li, C.K., Li, G., Li, M.S., Li, W., Li, X., Li, X.B., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liao, J.Y., Liu, G.Q., Liu, H.W., Liu, X.J., Liu, Y.N., Lu, B., Lu, X.F., Luo, Q., Luo, T., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Sai, N., Shang, R.C., Song, X.Y., Sun, L., Tan, Y., Tuo, Y.L., Wang, C., Wang, G.F., Wang, J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.Y., Wu, B.B., Wu, M., Xiao, S., Xiong, S.L., Yang, J.W., Yang, S., Yang, Y.J., Yin, Q.Q., Yi, Q.B., You, Y., Zhang, A.M., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, T., Zhang, W.C., Zhang, W.Z., Zhang, Y., Zhang, Y.F., Zhang, Y.J., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zhou, D.K., Zhou, J.F., Zhu, Y.X., Zhu, Y., and Zhuang, R.L.
Published: 2020
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38. Insight-HXMT observation on 4U 1608–52: Evolving spectral properties of a bright type-I X-ray burst

Author: Chen, Y.P., Zhang, S., Zhang, S.N., Ji, L., Kong, L.D., Santangelo, A., Qu, J.L., Lu, F.J., Li, T.P., Song, L.M., Xu, Y.P., Cao, X.L., Chen, Y., Liu, C.Z., Bu, Q.C., Cai, C., Chang, Z., Chen, G., Chen, L., Chen, T.X., Chen, Y.B., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Ge, M.Y., Gu, Y.D., Guan, J., Guo, C.C., Han, D.W., Huang, Y., Huo, J., Jia, S.M., Jiang, L.H., Jiang, W.C., Jin, J., Li, B., Li, C.K., Li, G., Li, M.S., Li, W., Li, X., Li, X.B., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liao, J.Y., Liu, G.Q., Liu, H.W., Liu, X.J., Liu, Y.N., Lu, B., Lu, X.F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Ren, X.Q., Sai, N., Sun, L., Tan, Y., Tao, L., Tuo, Y.L., Wang, C., Wang, G.F., Wang, J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.Y., Wu, B.B., Wu, M., Xiao, G.C., Xiao, S., Xiong, S.L., Yang, J.W., Yang, S., Yang, Y.J., Yi, Q.B., Yin, Q.Q., You, Y., Zhang, A.M., Zhang, C.L., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, T., Zhang, W.C., Zhang, W., Zhang, W.Z., Zhang, Yi., Zhang, Y.F., Zhang, Y.J., Zhang, Y., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zhou, D.K., Zhou, J.F., Zhu, Y., and Zhu, Y.X.
Published: 2019
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39. Constant cyclotron line energy in Hercules X–1 - Joint Insight-HXMT and NuSTAR observations

Author: Xiao, G.C., Ji, L., Staubert, R., Ge, M.Y., Zhang, S., Zhang, S.N., Santangelo, A., Ducci, L., Liao, J.Y., Guo, C.C., Li, X.B., Zhang, W., Qu, J.L., Lu, F.J., Li, T.P., Song, L.M., Xu, Y.P., Bu, Q.C., Cai, C., Cao, X.L., Chang, Z., Chen, G., Chen, L., Chen, T.X., Chen, Y.B., Chen, Y., Chen, Y.P., Cui, W., Cui, W.W., Deng, J.K., Dong, Y.W., Du, Y.Y., Fu, M.X., Gao, G.H., Gao, H., Gao, M., Gu, Y.D., Guan, J., Gungor, C., Han, D.W., Huang, Y., Huo, J., Jia, S.M., Jiang, L.H., Jiang, W.C., Jin, J., Kong, L.D., Li, B., Li, C.K., Li, G., Li, M.S., Li, W., Li, X., Li, X.F., Li, Y.G., Li, Z.W., Liang, X.H., Liu, C.Z., Liu, G.Q., Liu, H.W., Liu, X.J., Liu, Y.N., Lu, B., Lu, X.F., Luo, Q., Luo, T., Ma, X., Meng, B., Nang, Y., Nie, J.Y., Ou, G., Sai, N., Song, S.X., Sun, L., Tan, Y., Tao, L., Tuo, Y.L., Wang, C., Wang, G.F., Wang, J., Wang, W.S., Wang, Y.S., Wen, X.Y., Wu, B.B., Wu, B.Y., Wu, M., Xiong, S.L., Yang, J.W., Yang, S., Yang, Y.J., Yin, Q.B., Yin, Q.Q., Zhang, A.M., Zhang, C.M., Zhang, F., Zhang, H.M., Zhang, J., Zhang, T., Zhang, W.C., Zhang, W.Z., Zhang, Y., Zhang, Y.F., Zhang, Y.J., Zhang, Z., Zhang, Z.L., Zhao, H.S., Zhao, X.F., Zheng, S.J., Zhou, J.F., Zhu, Y., and Zhu, Y.X.
Published: 2019
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40. Theoretical Modeling and Evaluation of Thermal Stress Evolution of Concrete at Early Age by Temperature Stress Testing Machine

Author: Ou, G. F., primary, Kishi, T., additional, Lin, Z. H., additional, and Kamada, T., additional
Published: 2020
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41. Erosion Characteristics and Flashing Flow of High-differential-pressure Control Valves: A Numerical Study using an Erosion-Coupled Dynamic Mesh.

Author: Ou, G. F., Wang, C. G., and Jin, H. Z.
Subjects: VALVES, EROSION, COMPUTATIONAL fluid dynamics, FLOW coefficient, CHEMICAL systems, ANNULAR flow
Abstract: To address the issue of erosion in the control valves of blackwater flash systems in the coal chemical industry, this study investigates the dynamic erosion characteristics of one such control valve. Computational fluid dynamics is employed to compare the results obtained with a static mesh and an erosioncoupled dynamic mesh, and the valve erosion is investigated by analyzing the erosion rate, the particle impact velocity, trajectories and angle. Moreover, the relationship between the deformation caused by erosion and the dispersion of the flash vapor phase in the valve is studied, focusing on the flow resistance coefficient. The results indicate that over a period of 9 Ã--106 s, the impact velocity and subsequent collisions of particles reduce, and the impact angle decreases with the accumulated deformation of the valve core. Notably, the valve core is influenced primarily by the cutting that results from low impact angles, leading to a substantial decrease in the overall erosion rate of the valve, amounting to a reduction of 56.4%. The region facing the flow is at significant risk of erosion, and as the opening decreases, the erosion zone extends gradually to the annular region of the valve core and valve head, leading to increased erosion deformation. Furthermore, as the flow resistance coefficient decreases, so does the vapor volume fraction inside the valve. This study provides a theoretical basis for predicting faults and developing online monitoring solutions for high-differential-pressure control valves in blackwater flashing systems. [ABSTRACT FROM AUTHOR]
Published: 2024
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42. Microemulsions vs chitosan derivative-coated microemulsions for dermal delivery of 8-methoxypsoralen

Author: Wu JY, Li YJ, Liu TT, Ou G, Hu XB, Tang TT, Wang JM, Liu XY, and Xiang DX
Subjects: Vitiligo, 8-methoxypsoralen, microemulsion, chitosan coated microemulsion, ex vivo permeation, microdialysis, pharmacokinetics, Medicine (General), R5-920
Abstract: Jun-Yong Wu,1–3,* Yong-Jiang Li,1–3,* Ting-Ting Liu,1–3 Ge Ou,1–3 Xiong-Bin Hu,1–3 Tian-Tian Tang,1–3 Jie-Min Wang,1–3 Xin-Yi Liu,1–3 Da-Xiong Xiang1–3 1Department of Pharmacy, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, People’s Republic of China; 2Institute of Clinical Pharmacy, Central South University, Changsha, Hunan 410011, People’s Republic of China; 3Hunan Provincial Engineering Research Center of Translational Medicine and Innovative Drugs, Changsha, Hunan, People’s Republic of China *These authors contributed equally to this work Background: 8-methoxypsoralen (8-MOP) is one of the most commonly utilized drugs in psoralen-ultraviolet A therapy for treatment of vitiligo. However, poor skin retention and systemic side effects limit the clinical application of 8-MOP. Methods: Microemulsions (MEs) and chitosan derivative-coated 8-MOP MEs were developed and compared for dermal delivery of 8-MOP. Ex vivo skin retention/permeation study was performed to select the ME formulation with the highest retention:permeation ratio. Four different chitosan-coated MEs were prepared and compared with the ME formulation for their ability to distribute 8-MOP in the skin.Results: Among various ME formulations developed, a formulation containing 2.9% ethyl oleate, 17.2% Cromophor EL35, 8.6% ethanol and 71.3% water showed the highest ex vivo skin retention:permeation ratio (1.98). Of four chitosan-coated MEs prepared, carboxymethyl chitosan-coated MEs (CC-MEs) and hydroxypropyl chitosan-coated MEs (HC-MEs) showed higher ex vivo skin retention:permeation ratio (1.46 and 1.84). and were selected for in vivo pharmacokinetic study. AUCskin (0–12 h) for 8-MOP MEs (4578.56 h·ng·mL-1) was higher than HC-MEs (3422.47 h·ng·mL-1), CC-MEs (2808.51 h·ng·mL-1) and tincture (1500.16 h·ng·mL-1). Also, AUCplasma (0–12 h) for MEs (39.35±13.90 h·ng·mL-1) was significantly lower than HC-MEs (66.32 h·ng·mL-1), CC-MEs (59.70 h·ng·mL-1) and tincture (73.02 h·ng·mL-1).Conclusion: These combined results suggested that the MEs developed could be a promising and safe alternative for targeted skin delivery of 8-MOP. Keywords: 8-methoxypsoralen, microemulsion, chitosan-coated microemulsion, ex vivo permeation, microdialysis, pharmacokinetics
Published: 2019

43. Mechanism of transport of IFT particles in C-elegans cilia by the concerted action of kinesin-II and OSM-3 motors

Author: Pan, X Y, Ou, G S, Civelekoglu-Scholey, G, Blacque, O E, Endres, N F, Tao, L, Mogilner, A, Leroux, M R, Vale, Ronald D, and Scholey, J M
Abstract: The assembly and function of cilia on Caenorhabditis elegans neurons depends on the action of two kinesin-2 motors, heterotrimeric kinesin-II and homodimeric OSM-3-kinesin, which cooperate to move the same intraflagellar transport (IFT) particles along microtubule (MT) doublets. Using competitive in vitro MT gliding assays, we show that purified kinesin-II and OSM-3 cooperate to generate movement similar to that seen along the cilium in the absence of any additional regulatory factors. Quantitative modeling suggests that this could reflect an alternating action mechanism, in which the motors take turns to move along MTs, or a mechanical competition, in which the motors function in a concerted fashion to move along MTs with the slow motor exerting drag on the fast motor and vice versa. In vivo transport assays performed in Bardet-Biedl syndrome (BBS) protein and IFT motor mutants favor a mechanical competition model for motor coordination in which the IFT motors exert a BBS protein-dependent tension on IFT particles, which controls the IFT pathway that builds the cilium foundation.
Published: 2006

44. Two anterograde intraflagellar transport motors cooperate to build sensory cilia on C-elegans neurons

Author: Snow, J J, Ou, G S, Gunnarson, A L, Walker, MRS, Zhou, H M, Brust-Mascher, I, and Scholey, Jonathan M
Abstract: Cilia have diverse roles in motility and sensory reception and their dysfunction contributes to cilia-related diseases. Assembly and maintenance of cilia depends on the intraflagellar transport (IFT) of axoneme, membrane, matrix and signalling proteins to appropriate destinations within the organelle(1-4). In the current model, these diverse cargo proteins bind to multiple sites on macromolecular IFT particles, which are moved by a single anterograde IFT motor, kinesin-II, from the ciliary base to its distal tip(5,6), where cargo-unloading occurs(1-4,7). Here, we describe the observation of fluorescent IFT motors and IFT particles moving along distinct domains within sensory cilia of wild-type and IFT-motor-mutant Caenorhabditis elegans. We show that two anterograde IFT motor holoenzymes, kinesin-II and Osm-3-kinesin(8), cooperate in a surprising way to control two pathways of IFT that build distinct parts of cilia. Instead of each motor independently moving its own specific cargo to a distinct destination, the two motors function redundantly to transport IFT particles along doublet microtubules adjacent to the transition zone to form the axoneme middle segment(9). Next, Osm-3-kinesin alone transports IFT particles along the distal singlet microtubules to stabilize the distal segment. Thus, the subtle coordinate activity of these IFT motors creates two sequential transport pathways.
Published: 2004

45. A223 UNMASKED OR INDUCED COLITIS: COULD IT BE SECUKINUMAB?

Author: Nassiri, S, primary, Ou, G, additional, and Xiong, W, additional
Published: 2023
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46. Comparison of 16S rRNA gene PCR and blood culture for diagnosis of neonatal sepsis

Author: Liu, C.L., Ai, H.W., Wang, W.P., Chen, L., Hu, H.B., Ye, T., Zhu, X.H., Wang, F., Liao, Y.L., Wang, Y., Ou, G., Xu, L., Sun, M., Jian, C., Chen, Z.J., Li, L., Zhang, B., Tian, L., Wang, B., Yan, S., and Sun, Z.Y.
Published: 2014
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47. Polydopamine deposition with anodic oxidation for better connective tissue attachment to transmucosal implants

Author: Teng, F., Chen, H., Xu, Y., Liu, Y., and Ou, G.
Published: 2018
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48. Analysis of postcytokinetic roles of cytokinetic components in Caenorhabditis elegans

Author: Chai, Y., primary, Tian, D., additional, Li, W., additional, and Ou, G., additional
Published: 2017
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49. Identification of de-bonding between steel bars and concrete using wavelet techniques: Comparative study

Author: Ou, G, Wang, Y, Hao, H, and Zhu, XQ
Published: 2013

50. Formation of BaF₂ microcrystals as superhydrophobic materials via a hydrothermal method

Author: Ma, J. (Jinxiu), Ou, G. (Gaoyu), Li, T. (Taohai), Li, F. (Feng), Ma, J. (Jinxiu), Ou, G. (Gaoyu), Li, T. (Taohai), and Li, F. (Feng)
Abstract: Controllable BaF₂ microcrystals with super-hydrophobic property have been successfully synthesized via a facile hydrothermal process. XRD, SEM and CA were used to study the structure, morphology and the hydrophobic properties of the BaF₂ materials. The effects of reaction time, surfactants and pH were investigated in order to get a series of accurate reaction conditions for the preparation of BaF₂ material. The results showed that uniform BaF₂ cubic phase structure was fabricated when the reaction temperature was controlled at 160 °C for 24 h. In addition, the BaF₂ materials showed excellent super-hydrophobic properties. The results of the influence of time and substrates exhibited that the sample could maintain the stable super-hydrophobic property for over 10 days. As a promising superhydrophobic material, the studies of BaF₂ reported in this paper have potential application prospect and have a certain guiding meaning for the future study about superhydrophobic materials.
Published: 2022

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