The Gravitational wave burst high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a dedicated mission for monitoring high-energy transients.Here we report the design of the GECAM Scientific Ground Segment(...The Gravitational wave burst high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a dedicated mission for monitoring high-energy transients.Here we report the design of the GECAM Scientific Ground Segment(GSGS)in terms of the scientific requirements,including the architecture,the external interfaces,the main function,and workflow.Judging from the analysis and verification results during the commissioning phase,the GSGS functions well and is able to monitor the status of the payloads,adjust the parameters,develop the scientific observation plans,generate the scientific data products,analyze the data,etc.Thus,the on-orbit operation and scientific researches of GECAM are guaranteed.展开更多
Objective:To study the preventive effect of Timosaponin BII(T-BII)-loaded temperature/ion-sensitive nasal in situ hydrogels(ISGs)on Alzheimer's disease(AD),its preparation technology,characteristics and in vivo ef...Objective:To study the preventive effect of Timosaponin BII(T-BII)-loaded temperature/ion-sensitive nasal in situ hydrogels(ISGs)on Alzheimer's disease(AD),its preparation technology,characteristics and in vivo effects were evaluated.Methods:The morphological and rheological properties were evaluated.The preventive effects of T-BII ISG on scopolamine-induced AD in mice were determined with the index of muscarinicreceptor 1(M1)expression and pathological changes.Results:Results revealed that T-BII ISG significantly increased the content of M1 choline receptors in the hippocampus of mice and ameliorated the damage incurred to the hippocampal cornu ammonis 1(CA1)area.Conclusion:T-BII ISGs is a reasonable and convenient method of exerting an obvious preventive effect on mice with AD induced by scopolamine.This,thereby,lays forth a new treatment option for preventing AD.展开更多
Purpose The Einstein Probe(EP)satellite is equipped with the Wide-field X-ray Telescope(WXT)and the Follow-up X-ray Telescope(FXT).The EP-FXT Workflow Management System is part of the FXT-SDC and is responsible for ma...Purpose The Einstein Probe(EP)satellite is equipped with the Wide-field X-ray Telescope(WXT)and the Follow-up X-ray Telescope(FXT).The EP-FXT Workflow Management System is part of the FXT-SDC and is responsible for managing the workflow involved in data product generation.It is utilized for the fully automated processing of FXT data within the pipeline for generating data products.Methods The EP-FXT Workflow Management System invokes computing servers by leveraging the computing resource scheduling platform HTCondor,constructs workflows through the workflow orchestration platform Dolphineschedule,detects data via the central control website,automatically triggers workflows,monitors the workflow processing procedure,and provides a feedback and redo mechanism.Results The workflow processing was automatically initiated 16,900 times for 4000 observations within 270 days,and approximately 40,000 files are archived daily.The system handles both standalone servers and computing clusters.Under the circumstances of sufficient resources where tasks do not need to wait,when utilizing the resources of standalone server,the average time for task switching is 1.4 s.In contrast,when using the computing cluster,the average time for task switching is 2.7 s.Regarding the Observation Data Workflow,26.91%of the tasks are completed within 10 min,and 71.7%are completed within 100 min.Conclusion The EP-FXT Workflow Management System is capable of effectively expediting the generation of data products.展开更多
We present the observational results from a detailed timing analysis of the black hole candidate EXO 1846-031 during its outburst in 2019 with the observations of Insight-HXMT,NICER and MAXI.This outburst can be class...We present the observational results from a detailed timing analysis of the black hole candidate EXO 1846-031 during its outburst in 2019 with the observations of Insight-HXMT,NICER and MAXI.This outburst can be classified roughly into four different states.Type-C quasi-periodic oscillations(QPOs)observed by NICER(about 0.1-6 Hz)and Insight-HXMT(about 0.7-8 Hz)are also reported in this work.Meanwhile,we study various physical quantities related to QPO frequency.The QPO rms-frequency relationship in the energy band 1-10 keV indicates that there is a turning pointing in frequency around2 Hz,which is similar to that of GRS 1915+105.A possible hypothesis for the relationship above may be related to the inclination of the source,which may require a high inclination to explain it.The relationships between QPO frequency and QPO rms,hardness,total fractional rms and count rate have also been found in other transient sources,which can indicate that the origin of type-C QPOs is non-thermal.展开更多
In this paper,we present the current status of the enhanced X-ray Timing and Polarimetry mission,which has been fully approved for launch in 2030.eXTP is a space science mission designed to study fundamental physics u...In this paper,we present the current status of the enhanced X-ray Timing and Polarimetry mission,which has been fully approved for launch in 2030.eXTP is a space science mission designed to study fundamental physics under extreme conditions of matter density,gravity,and magnetism.The mission aims at determining the equation of state of matter at supra-nuclear density,measuring the effects of quantum electro-dynamics,and understanding the dynamics of matter in strong-field gravity.In addition to investigating fundamental physics,the eXTP mission is poised to become a leading observatory for time-domain and multi-messenger astronomy in the 2030s,as well as providing observations of unprecedented quality on a variety of galactic and extragalactic objects.After briefly introducing the history and a summary of the scientific objectives of the eXTP mission,this paper presents a comprehensive overview of:(1)the cutting-edge technology,technical specifications,and anticipated performance of the mission’s scientific instruments;(2)the full mission profile,encompassing spacecraft design,operational capabilities,and ground segment infrastructure.展开更多
Background:The Einstein Probe(EP)is a space X-ray astronomical mission of China-Europe collaboration,launched on January 9,2024,and is equipped with two types of scientific payloads,the wide-field X-ray telescope(WXT)...Background:The Einstein Probe(EP)is a space X-ray astronomical mission of China-Europe collaboration,launched on January 9,2024,and is equipped with two types of scientific payloads,the wide-field X-ray telescope(WXT)and the follow-up X-ray telescope(FXT).Methods:The FXT payload was developed by the Institute of High Energy Physics(IHEP).Consequently,the EP-FXT Science Data Center(SDC)was established at IHEP to manage the processing of FXT data.Results and conclusion:The EP-FXT SDC has maintained a continuous and stable operation since the EP’s launch.It has provided the standard data products,released the data analysis software and calibration database,and supported the science users in conducting scientific research.In this paper,we present a systematic and comprehensive overview of the primary workflows and key tasks of the FXT science data center.展开更多
Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, cosmology and fundament...Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, cosmology and fundamental physics. On Aug. 17, 2017, Advanced LIGO and Fermi/GBM independently triggered the first BNS merger, GW170817, and its high energy EM counterpart, GRB 170817A, respectively, resulting in a global observation campaign covering gamma-ray, X-ray, UV, optical, IR, radio as well as neutrinos. The High Energy X-ray telescope (HE) onboard Insight-HXMT (Hard X-ray Modulation Telescope) is the unique high-energy gamma-ray telescope that monitored the entire GW localization area and especially the optical counterpart (SSS17a/AT2017gfo) with very large collection area (M000 cm2) and microsecond time resolution in 0.2-5 MeV. In addition, Insight-HXMT quickly implemented a Target of Opportunity (TOO) observation to scan the GW localization area for potential X-ray emission from the GW source. Although Insight-HXMT did not detect any significant high energy (0.2-5 MeV) radiation from GW170817, its observation helped to confirm the unexpected weak and soft nature of GRB 170817A. Meanwhile, Insight-HXMT/HE provides one of the most stringent constraints (-10-7 to 104 erg/cm2/s) for both GRB170817A and any other possible precursor or extended emissions in 0.2-5 MeV, which help us to better understand the properties of EM radiation from this BNS merger. Therefore the observation of Insight-HXMT constitutes an important chapter in the full context of multi-wavelength and multi-messenger observation of this historical GW event.展开更多
Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficienc...Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficiency and increased side effects.In this study,nasal cannabidiol inclusion complex temperature-sensitive hydrogels(CBD TSGs)were prepared and evaluated to treat PTSD.Mice model of PTSD was established with conditional fear box.CBD TSGs could significantly improve the spontaneous behavior,exploratory spirit and alleviate tension in open field box,relieve anxiety and tension in elevated plus maze,and reduce the freezing time.Hematoxylin and eosin and c-FOS immunohistochemistry slides showed that the main injured brain areas in PTSD were the prefrontal cortex,amygdala,and hippocampus CA1.CBD TSGs could reduce the level of tumor necrosis factor-a caused by PTSD.Western blot analysis showed that CBD TSGs increased the expression of the 5-HT1 A receptor.Intranasal administration of CBD TSGs was more efficient and had more obvious brain targeting effects than oral administration,as evidenced by the pharmacokinetics and brain tissue distribution of CBD TSGs.Overall,nasal CBD TSGs are safe and effective and have controlled release.There are a novel promising option for the clinical treatment of PTSD.展开更多
Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is primarily designed to spot gamma-ray bursts corresponding to gravitational waves.In order to achieve stable observatio...Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is primarily designed to spot gamma-ray bursts corresponding to gravitational waves.In order to achieve stable observations from various astronomical phenomena,the payload performance need to be monitored during the in-orbit operation.Method This article describes the design and implementation of GECAM satellite payload performance monitoring(GPPM)software.The software extracts the payload status and telescope observations(light curves,energy spectrums,characteristic peak fitting of energy spectrums,etc)from the payload data.Considering the large amount of payload status parameters in the engineering data,we have designed a method of parameter processing based on the configuration tables.This method can deal with the frequent changes of the data formats and facilitate program maintenance.Payload status and performance are monitored through defined thresholds and monitoring reports.The entire software is implemented in python language and the huge amount of observation data is stored in MongoDB.Conclusion The design and implementation of GPPM software have been completed,tested with ground and in-orbit payload data.The software can monitor the performance of GECAM payload effectively.The overall design of the software and the data processing method can be applied to other satellites.展开更多
As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray as...As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 Me V. It was designed to perform pointing, scanning and gamma-ray burst(GRB)observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be reconstructed.Here we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results.展开更多
We investigate high time resolution data obtained by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)during the flare event on 2022 April 21 at 01:52 UT.Several subpeaks with durat...We investigate high time resolution data obtained by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)during the flare event on 2022 April 21 at 01:52 UT.Several subpeaks with durations of 4-6 s have been detected in the hard X-ray precursor phase,and the key feature is that they appear in pairs and seem like double-peak struc-tures.These subpeaks are rarely observed in hard X-ray band and confirmed by the microwave obtained by Nobeyama Radio Polarimeters(NoRP)and Radio Solar Telescope Network(RSTN).While an exponential function can describe the continuum component of the time profile from the precursor to part of the impulsive phase.The periods of quasi-periodic pulsations(QPPs)are detected to be about 7.3 and 12.8 s for the precursor and impulsive phase,respectively,with at least 95%confidence level.The paired QPPs are assumed to be double-peak QPPs and then the scenario of current loop coalescence model is found to be in good agreement with our observation.The precursor phase can be interpreted as the oscillating coalescence of two islands,while the impulsive phase can be interpreted as more islands to coalesce one by one to form larger islands.展开更多
Purpose The LHAASO project collects trillions of cosmic ray events every year,generating about 10 PB of raw data annually,which brings big challenges for data processing platform.Method The LHAASO data processing plat...Purpose The LHAASO project collects trillions of cosmic ray events every year,generating about 10 PB of raw data annually,which brings big challenges for data processing platform.Method The LHAASO data processing platform is built to handle such a large amount of data,which is composed of some subsystems such as data transfer,data storage,high throughput computing and metadata management.Results and conclusions The platform was under construction since 2018 and has been working well since 2021.In this paper,the details of the design,implementation and performance of the data processing platform are presented.展开更多
基金supported by the National Key R&D Program of China(2022YFF0711404,2021YFA0718500)International Partnership Program of Chinese Academy of Sciences(grant No.113111KYSB20190020)+2 种基金the National Natural Science Foundation of China(NSFC,Grant No.U1938106)the open subject of the National HEP Data Center(E029S2S1)support from the Strategic Priority Research Program on Space Science,the Chinese Academy of Sciences(grant Nos.XDA15360102,XDA15360300,XDA15052700 and E02212A02S)。
文摘The Gravitational wave burst high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a dedicated mission for monitoring high-energy transients.Here we report the design of the GECAM Scientific Ground Segment(GSGS)in terms of the scientific requirements,including the architecture,the external interfaces,the main function,and workflow.Judging from the analysis and verification results during the commissioning phase,the GSGS functions well and is able to monitor the status of the payloads,adjust the parameters,develop the scientific observation plans,generate the scientific data products,analyze the data,etc.Thus,the on-orbit operation and scientific researches of GECAM are guaranteed.
基金This study was funded by the Beijing Natural Science Foundation(7202147).
文摘Objective:To study the preventive effect of Timosaponin BII(T-BII)-loaded temperature/ion-sensitive nasal in situ hydrogels(ISGs)on Alzheimer's disease(AD),its preparation technology,characteristics and in vivo effects were evaluated.Methods:The morphological and rheological properties were evaluated.The preventive effects of T-BII ISG on scopolamine-induced AD in mice were determined with the index of muscarinicreceptor 1(M1)expression and pathological changes.Results:Results revealed that T-BII ISG significantly increased the content of M1 choline receptors in the hippocampus of mice and ameliorated the damage incurred to the hippocampal cornu ammonis 1(CA1)area.Conclusion:T-BII ISGs is a reasonable and convenient method of exerting an obvious preventive effect on mice with AD induced by scopolamine.This,thereby,lays forth a new treatment option for preventing AD.
基金supported by the Einstein Probe(EP)Program which is funded by the Strategic Priority Research Program of the Chinese Academy of Sciences Grant No.XDA15310303.
文摘Purpose The Einstein Probe(EP)satellite is equipped with the Wide-field X-ray Telescope(WXT)and the Follow-up X-ray Telescope(FXT).The EP-FXT Workflow Management System is part of the FXT-SDC and is responsible for managing the workflow involved in data product generation.It is utilized for the fully automated processing of FXT data within the pipeline for generating data products.Methods The EP-FXT Workflow Management System invokes computing servers by leveraging the computing resource scheduling platform HTCondor,constructs workflows through the workflow orchestration platform Dolphineschedule,detects data via the central control website,automatically triggers workflows,monitors the workflow processing procedure,and provides a feedback and redo mechanism.Results The workflow processing was automatically initiated 16,900 times for 4000 observations within 270 days,and approximately 40,000 files are archived daily.The system handles both standalone servers and computing clusters.Under the circumstances of sufficient resources where tasks do not need to wait,when utilizing the resources of standalone server,the average time for task switching is 1.4 s.In contrast,when using the computing cluster,the average time for task switching is 2.7 s.Regarding the Observation Data Workflow,26.91%of the tasks are completed within 10 min,and 71.7%are completed within 100 min.Conclusion The EP-FXT Workflow Management System is capable of effectively expediting the generation of data products.
基金the HXMT mission,a project funded by China National Space Administration(CNSA)and the Chinese Academy of Sciences(CAS)supported by the National Key R&D Program of China(2016YFA0400800)the National Natural Science Foundation of China(Grant Nos.11673023,U1838201,U1838115,U1838111,U1838202,11733009 and U1838108)。
文摘We present the observational results from a detailed timing analysis of the black hole candidate EXO 1846-031 during its outburst in 2019 with the observations of Insight-HXMT,NICER and MAXI.This outburst can be classified roughly into four different states.Type-C quasi-periodic oscillations(QPOs)observed by NICER(about 0.1-6 Hz)and Insight-HXMT(about 0.7-8 Hz)are also reported in this work.Meanwhile,we study various physical quantities related to QPO frequency.The QPO rms-frequency relationship in the energy band 1-10 keV indicates that there is a turning pointing in frequency around2 Hz,which is similar to that of GRS 1915+105.A possible hypothesis for the relationship above may be related to the inclination of the source,which may require a high inclination to explain it.The relationships between QPO frequency and QPO rms,hardness,total fractional rms and count rate have also been found in other transient sources,which can indicate that the origin of type-C QPOs is non-thermal.
基金the support of the National Natural Science Foundation of China(Grant No.12333007)the International Partnership Program of Chinese Academy of Sciences(Grant No.113111KYSB20190020)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA15020100)support by ASI,under the dedicated eXTP agreements and agreement ASI-INAF n.2017-14-H.O.by INAF and INFN under project REDSOXsupport from the Deutsche Zentrum für Luft-und Raumfahrt,the German Aerospace Center(DLR)support from MINECO grant ESP2017-82674-R and FEDER funds.
文摘In this paper,we present the current status of the enhanced X-ray Timing and Polarimetry mission,which has been fully approved for launch in 2030.eXTP is a space science mission designed to study fundamental physics under extreme conditions of matter density,gravity,and magnetism.The mission aims at determining the equation of state of matter at supra-nuclear density,measuring the effects of quantum electro-dynamics,and understanding the dynamics of matter in strong-field gravity.In addition to investigating fundamental physics,the eXTP mission is poised to become a leading observatory for time-domain and multi-messenger astronomy in the 2030s,as well as providing observations of unprecedented quality on a variety of galactic and extragalactic objects.After briefly introducing the history and a summary of the scientific objectives of the eXTP mission,this paper presents a comprehensive overview of:(1)the cutting-edge technology,technical specifications,and anticipated performance of the mission’s scientific instruments;(2)the full mission profile,encompassing spacecraft design,operational capabilities,and ground segment infrastructure.
基金supported by the Einstein-Probe(EP)Program which is funded by the Strategic Priority Research Program of the Chinese Academy of Sciences Grant No.XDA15310303.
文摘Background:The Einstein Probe(EP)is a space X-ray astronomical mission of China-Europe collaboration,launched on January 9,2024,and is equipped with two types of scientific payloads,the wide-field X-ray telescope(WXT)and the follow-up X-ray telescope(FXT).Methods:The FXT payload was developed by the Institute of High Energy Physics(IHEP).Consequently,the EP-FXT Science Data Center(SDC)was established at IHEP to manage the processing of FXT data.Results and conclusion:The EP-FXT SDC has maintained a continuous and stable operation since the EP’s launch.It has provided the standard data products,released the data analysis software and calibration database,and supported the science users in conducting scientific research.In this paper,we present a systematic and comprehensive overview of the primary workflows and key tasks of the FXT science data center.
基金supported by the National Program on Key Research and Development Project(Grant No.2016YFA0400800)from the Ministry of Science and Technology of China(MOST)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB23040400)the Hundred Talent Program of Chinese Academy of Sciences,the National Natural Science Foundation of China(Grant Nos.11233001,11503027,11403026,11473027,and11733009)
文摘Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, cosmology and fundamental physics. On Aug. 17, 2017, Advanced LIGO and Fermi/GBM independently triggered the first BNS merger, GW170817, and its high energy EM counterpart, GRB 170817A, respectively, resulting in a global observation campaign covering gamma-ray, X-ray, UV, optical, IR, radio as well as neutrinos. The High Energy X-ray telescope (HE) onboard Insight-HXMT (Hard X-ray Modulation Telescope) is the unique high-energy gamma-ray telescope that monitored the entire GW localization area and especially the optical counterpart (SSS17a/AT2017gfo) with very large collection area (M000 cm2) and microsecond time resolution in 0.2-5 MeV. In addition, Insight-HXMT quickly implemented a Target of Opportunity (TOO) observation to scan the GW localization area for potential X-ray emission from the GW source. Although Insight-HXMT did not detect any significant high energy (0.2-5 MeV) radiation from GW170817, its observation helped to confirm the unexpected weak and soft nature of GRB 170817A. Meanwhile, Insight-HXMT/HE provides one of the most stringent constraints (-10-7 to 104 erg/cm2/s) for both GRB170817A and any other possible precursor or extended emissions in 0.2-5 MeV, which help us to better understand the properties of EM radiation from this BNS merger. Therefore the observation of Insight-HXMT constitutes an important chapter in the full context of multi-wavelength and multi-messenger observation of this historical GW event.
基金funded by the Beijing Municipal Natural Science Foundation,China(7202147 and 7172072,China)
文摘Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficiency and increased side effects.In this study,nasal cannabidiol inclusion complex temperature-sensitive hydrogels(CBD TSGs)were prepared and evaluated to treat PTSD.Mice model of PTSD was established with conditional fear box.CBD TSGs could significantly improve the spontaneous behavior,exploratory spirit and alleviate tension in open field box,relieve anxiety and tension in elevated plus maze,and reduce the freezing time.Hematoxylin and eosin and c-FOS immunohistochemistry slides showed that the main injured brain areas in PTSD were the prefrontal cortex,amygdala,and hippocampus CA1.CBD TSGs could reduce the level of tumor necrosis factor-a caused by PTSD.Western blot analysis showed that CBD TSGs increased the expression of the 5-HT1 A receptor.Intranasal administration of CBD TSGs was more efficient and had more obvious brain targeting effects than oral administration,as evidenced by the pharmacokinetics and brain tissue distribution of CBD TSGs.Overall,nasal CBD TSGs are safe and effective and have controlled release.There are a novel promising option for the clinical treatment of PTSD.
基金This work is supported by the Strategic Prior-ity Research Program of Chinese Academy of Sciences(Grant Nos.XDA15360300,XDA15360302 and XDB23040400).
文摘Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is primarily designed to spot gamma-ray bursts corresponding to gravitational waves.In order to achieve stable observations from various astronomical phenomena,the payload performance need to be monitored during the in-orbit operation.Method This article describes the design and implementation of GECAM satellite payload performance monitoring(GPPM)software.The software extracts the payload status and telescope observations(light curves,energy spectrums,characteristic peak fitting of energy spectrums,etc)from the payload data.Considering the large amount of payload status parameters in the engineering data,we have designed a method of parameter processing based on the configuration tables.This method can deal with the frequent changes of the data formats and facilitate program maintenance.Payload status and performance are monitored through defined thresholds and monitoring reports.The entire software is implemented in python language and the huge amount of observation data is stored in MongoDB.Conclusion The design and implementation of GPPM software have been completed,tested with ground and in-orbit payload data.The software can monitor the performance of GECAM payload effectively.The overall design of the software and the data processing method can be applied to other satellites.
基金project funded by China National Space Administration(CNSA)and the Chinese Academy of Sciences(CAS)support from the National Key Research and Development Program of China(Grant No.2016YFA0400800)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA04010202,XDA04010300,and XDB23040400)the National Natural Science Foundation of China(Grant Nos.U1838201,and U1838102).
文摘As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 Me V. It was designed to perform pointing, scanning and gamma-ray burst(GRB)observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be reconstructed.Here we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results.
基金supported by the National Natural Science Foundation of China (Grant Nos. U1938102, and 11973092)the National Program on Key Research and Development Project (Grant No. 2016YFA0400802)supported by the Surface Project of Jiangsu Province (Grant No. BK20211402)
文摘We investigate high time resolution data obtained by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)during the flare event on 2022 April 21 at 01:52 UT.Several subpeaks with durations of 4-6 s have been detected in the hard X-ray precursor phase,and the key feature is that they appear in pairs and seem like double-peak struc-tures.These subpeaks are rarely observed in hard X-ray band and confirmed by the microwave obtained by Nobeyama Radio Polarimeters(NoRP)and Radio Solar Telescope Network(RSTN).While an exponential function can describe the continuum component of the time profile from the precursor to part of the impulsive phase.The periods of quasi-periodic pulsations(QPPs)are detected to be about 7.3 and 12.8 s for the precursor and impulsive phase,respectively,with at least 95%confidence level.The paired QPPs are assumed to be double-peak QPPs and then the scenario of current loop coalescence model is found to be in good agreement with our observation.The precursor phase can be interpreted as the oscillating coalescence of two islands,while the impulsive phase can be interpreted as more islands to coalesce one by one to form larger islands.
基金supported by National Nature Science Foundation of China(GrantNos.12075268,12175255,12175258,12105300)the Chinese Academy of Science,Institute of High Energy Physics.
文摘Purpose The LHAASO project collects trillions of cosmic ray events every year,generating about 10 PB of raw data annually,which brings big challenges for data processing platform.Method The LHAASO data processing platform is built to handle such a large amount of data,which is composed of some subsystems such as data transfer,data storage,high throughput computing and metadata management.Results and conclusions The platform was under construction since 2018 and has been working well since 2021.In this paper,the details of the design,implementation and performance of the data processing platform are presented.