The melon thrips, Thrips palmi Karny, is an economically important pest on many vegetables from Solanaceae and Cucurbitaceae. In this study, we developed novel microsatellite markers for Thrips palmi. First, we obtain...The melon thrips, Thrips palmi Karny, is an economically important pest on many vegetables from Solanaceae and Cucurbitaceae. In this study, we developed novel microsatellite markers for Thrips palmi. First, we obtained randomly sequenced regions from the genome using next-generation sequencing and assembled 356 Mb genomic sequences. In total, 155,789 microsatellites were identified from the genomic sequences, of which, 64.02% were loci of dinucleotide repeat. Sixty primer pairs were initially validated in seven individuals. Thirty-five polymorphic markers were retained according to the amplification efficiency and polymorphism.These 35 microsatellite loci were then assessed in 96 individuals in four geographical populations collected from China. The allele numbers ranged from 2 to 19 with an average value of 6.9 per locus, while the polymorphism information content ranged from 0.2219 to 0.8490.The observed and expected heterozygosity varied from 0.5252 to 0.5367 and 0.5934 to 0.6148,respectively. Genetic structure was found between populations from southern and northern China. These novel microsatellite markers developed in our study provide abundant molecular markers for the genetic study of T. palmi.展开更多
Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with ...Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in China exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in China.展开更多
The weevils Eucryptorrhynchus brandti(Harold)and E.scrobiculatus(Motschulsky)are two pests of the tree of heaven,Ailanthus altissima.They usually co-occur on their host tree.However,these two species have a niche sepa...The weevils Eucryptorrhynchus brandti(Harold)and E.scrobiculatus(Motschulsky)are two pests of the tree of heaven,Ailanthus altissima.They usually co-occur on their host tree.However,these two species have a niche separation with different eggs-laying locations and larvae-feeding parts on the tree.Here,we characterized the distribution of microsatellites in the genome and developed genome-wide microsatellite markers shared between these two weevils.A total of 12,524 and 11,030 potential microsatellites were identified for E.brandti and E.scrobiculatus,respectively.Microsatellites with AT,TA,AC,TG,CA repeat motifs were most common for both species.We designed primers universal for two weevils and developed 14 loci with high amplification efficacy and polymorphism.We validated these microsatellite markers in three populations of each species.In E.brandti,the observed and expected heterozygosity for the genotyped loci ranged from 0.17-0.24 and 0.44-0.54;in E.scrobiculatus,the above values ranged from 0.06-0.18 and 0.18-0.27.Based on the developed microsatellite markers,we found that populations of both weevils have a clear pattern of genetic differentiation.Our study provides valuable genetic markers for ecological,genetic,and evolutionary study of these two weevils.展开更多
The complete mitochondrial genome of the Gasteruption parvicollarium Enderlein （GenBank accession number： KR270643） was sequenced in the study. Totally 17 009 bp sequence was determined with an A＋T content of 83.8...The complete mitochondrial genome of the Gasteruption parvicollarium Enderlein （GenBank accession number： KR270643） was sequenced in the study. Totally 17 009 bp sequence was determined with an A＋T content of 83.81%, including full set of typical animal mitochondrial genes. Two protein-coding and 10 tRNA genes as well as the A＋T-rich region were rearranged compared with the putative ancestral arrangement of insects. Most of the rearranged genes were located in the ancestral region of trnl-trnQ-trnM-nad2-trn W-trnC-trn Y- coxl-trnL2. The other rearranged genes are trnN and trnS1 located in the tRNA cluster trnA- trnR-trnN-trnSl-trnE-trnF and trnS2 located between cob and nadl. Remote inversion is dominant rearrangement event in G. parvicollarium mitochondrial genome, involving two protein-coding and 8 tRNA genes. Compared with the other mitochondrial genome reported in the same genus of Gasteruption, the inverted trnN was translocated to the tRNA cluster between cox1 and nad2 in G. parvicollarium. This is the first report of mitochondrial gene rearrangement occurred within genus of Hymenoptera. Our study points to a recently occurred gene rearrangement event in the Gasteruption species.展开更多
Double-digested Restriction Site Associated DNA Sequencing（ddRAD） through next-generation sequencing（NGS） generates large numbers of loci for characterizing genomewide variation among multiple samples using next-g...Double-digested Restriction Site Associated DNA Sequencing（ddRAD） through next-generation sequencing（NGS） generates large numbers of loci for characterizing genomewide variation among multiple samples using next-generation sequencing. Different combinations of restriction endonucleases（REs） may produce varying size distributions of digested fragments, which affect the number of genotyped loci. Understanding digestion profiles across different species will help in selecting REs for digestion in a particular organism. In this study, we use of genome sequences to compare the in silico digestion profile of 26 combinations of REs in 131 insect species with two simulation programs. The number of digested fragments in the 300-450 bp range increases linearly with the size of the genome. Different species and insect orders showed similar profiles when digested by different combinations of REs in silico, indicating the conservation of digestion by double enzymes in insect genomes. Combinations with Nla III or TaqαI usually produced higher number of fragments in the range 300-450 bp, while combinations with EcoRI or MluCI produced fewer fragments. The proportion of fragments with the same overhangs at the two ends of digested DNA was higher than those with different overhangs. The two four-base enzyme pairs produced more fragments in the 300-450 bp range than pairs of four-base ＋ six-base enzymes. Experimental digestion of three species from Hymenoptera, Lepidoptera and Thysanoptera showed profiles congruent with in silico expectations. Our results shed light on understanding the digestion profiles of insect genomes and provide guidance on selecting REs for ddRAD projects.展开更多
Mitochondrial DNA(mtDNA)acts as a damage-associated molecular pattern to activate the stimulator of interferon genes(STING)signaling in macrophages,promoting tissue inflammation.However,its role in acute myocardial in...Mitochondrial DNA(mtDNA)acts as a damage-associated molecular pattern to activate the stimulator of interferon genes(STING)signaling in macrophages,promoting tissue inflammation.However,its role in acute myocardial infarction(AMI)remains unclear.Macrophage-specific Sting1 knockout mice were used to validate STING’s pathological role in AMI.Cardiac and liver mtDNA were used to activate macrophages in co-culture systems with cardiomyocytes to assess fibrosis and hypertrophy.Panaxatriol saponin(PTS)was tested for its ability to block mtDNA-driven macrophage activation and subsequent cardiomyocyte damage.STING-PTS binding ability was analyzed.AMI rats received PTS to evaluate its effects on myocardial inflammation and ventricular remodeling.In vivo,macrophage-specific Sting1 knockout reduced myocardial inflammation and injury after AMI.In vitro,mtDNA-activated macrophages induced cardiomyocyte fibrosis and hypertrophy through STING signaling.PTS suppressed mtDNA-driven macrophage activation by directly binding STING,thereby blocking inflammatory cascades.In AMI rats,PTS treatment attenuated acute inflammation and reversed ventricular remodeling.These findings establish the mtDNA-STING axis in macrophages as a critical driver of post-AMI inflammation and identify pharmacological STING inhibition with PTS as a promising therapeutic strategy.The study bridges genetic validation with translational applications,highlighting macrophage STING as a novel target for ischemic heart disease management.展开更多
Purpose Future large high-luminosity electron–positron colliders such as circular electron positron collider(CEPC)and future circular collider(FCC-ee)require nanometer-sized beams at the interaction point(IP).The lum...Purpose Future large high-luminosity electron–positron colliders such as circular electron positron collider(CEPC)and future circular collider(FCC-ee)require nanometer-sized beams at the interaction point(IP).The luminosity is very sensitive to the beam orbit drifts at the IP.It is essential to have a fast luminosity feedback system at the IP to maintain optimum beam collision conditions and prevent a luminosity degradation due to orbit drifts in the presence of mechanical vibrations and dynamical imperfections.Methods We considered two possible methods for this purpose for CEPC:one based on measurements of the luminosity and the other based on measurements of the beam orbits around the IP.Results In this paper,we present the preliminary design consideration for a fast luminosity feedback system at the IP of CEPC.展开更多
Correction to:Radiation Detection Technology and Methods(2024)8:1-1105.https://doi.org/10.1007/s41605-024-00463-y.In this article all authors name was missing in the springer link.It has been corrected.The original ar...Correction to:Radiation Detection Technology and Methods(2024)8:1-1105.https://doi.org/10.1007/s41605-024-00463-y.In this article all authors name was missing in the springer link.It has been corrected.The original article has been corrected.展开更多
Purpose In order to update the BPM electronic in BEPCII,a high-performance digital BPM processor is designed,and the RF front-end electronic is the key part in the digital BPM processor system.Methods According to the...Purpose In order to update the BPM electronic in BEPCII,a high-performance digital BPM processor is designed,and the RF front-end electronic is the key part in the digital BPM processor system.Methods According to the BEPCII physical parameters andADCunder-sampling theorem,the low-noise and high-dynamicrange RF front-end electronic module is designed.This article will introduce filter,RF amplifier,isolation,system test,etc.Results and conclusions The experimental results showed that BPM position short-term resolution is better than 100 nm,and long-term resolution is better than 5μm.It is the first domestic BPM processor that runs stably in the storage ring accelerator for a long time.Meanwhile,the study can help us to establish a solid foundation for the next work of BPM electronics development.展开更多
The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 3...The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.展开更多
Purpose Based on the requirements of the High Energy Photon Source(HEPS),the key components for strip-type and button-type beam position monitors(BPMs)and feedthroughs are designed and manufactured.Method The mechanic...Purpose Based on the requirements of the High Energy Photon Source(HEPS),the key components for strip-type and button-type beam position monitors(BPMs)and feedthroughs are designed and manufactured.Method The mechanical structure of the feedthroughs is designed according to the Computer Simulation Technology(CST)simulation results.Resultsandconclusions Small batches of feedthroughs are manufactured,and the structure is optimized based on mechanical,vacuum,electromagnetic,and other characteristic test results.The performance improved significantly owing to optimization through batch product testing,and quality control-related information from several manufacturers is obtained,which provide a foundation for the development of BPMs for HEPS.展开更多
Purpose Hundreds of digital beam position monitor processors(DBPM)are required to be produced during the construction of projects such as High Energy Photon Source(HEPS)and the upgrade project of the Beijing Electron ...Purpose Hundreds of digital beam position monitor processors(DBPM)are required to be produced during the construction of projects such as High Energy Photon Source(HEPS)and the upgrade project of the Beijing Electron Positron Collider(BEPCII),which brings great challenges to the test work.In order to achieve accurate,fast,and complete mass production tests of DBPMs,an automatic test system(ATS)has been developed in this article.Methods According to the test items of DBPM,the standardized testing softwareflow is designed based on virtual instru-ment program control technology and experimental physics and industrial control system(EPICS),which realize automatic adjustment of test parameters and automatic acquisition of test result data.Results and conclusions The ATS can realize one-button testing of channel coefficients,channel linearity,attenuator linearity,beam current dependence(BCD)and sampling signal-to-noise ratio(SNR),and generate test reports.The total test time is less than 3 minutes,which is significantly more efficient compared to manual testing.More than 90 BEPCII DBPMs has been tested by this ATS in the lab.The test results proved that such a system could automatically recognize defective products and satisfy the requirements of mass testing.展开更多
Background The current strategy to achieve high luminosity for high energy physics experiments is to store huge currents distributed in many bunches in circular machines such as BEPCII,so the longitudinal coupled bunc...Background The current strategy to achieve high luminosity for high energy physics experiments is to store huge currents distributed in many bunches in circular machines such as BEPCII,so the longitudinal coupled bunch instabilities of the beam are inevitable.Purpose Therefore,a longitudinal feedback system is needed to suppress longitudinal oscillation.Otherwise,the beam energy spread will increase;the luminosity and the beam lifetime will decrease under a certain beam current.Methods For filter design of the feedback system,the time domain least square fitting(TDLSF)method is compared to the selective wave filter method;digital signal processing electronics based on commercial board have been developed and tested on BEPCII.Results The final result shows that the self-developed longitudinal feedback system can suppress the longitudinal beam oscillation at 750 mA beam current and meet the requirements of BEPCII;the restrain depth to the sidebands reaches to 40.8 dB.展开更多
基金provided jointly by Promotion and Innovation of Beijing Academy of Agriculture and Forestry Sciences(KJCX20180113)the Natural Science Foundation of Beijing Municipality(6184037)Beijing Key Laboratory of Environmentally Friendly Pest Management on Northern Fruits(BZ0432)
文摘The melon thrips, Thrips palmi Karny, is an economically important pest on many vegetables from Solanaceae and Cucurbitaceae. In this study, we developed novel microsatellite markers for Thrips palmi. First, we obtained randomly sequenced regions from the genome using next-generation sequencing and assembled 356 Mb genomic sequences. In total, 155,789 microsatellites were identified from the genomic sequences, of which, 64.02% were loci of dinucleotide repeat. Sixty primer pairs were initially validated in seven individuals. Thirty-five polymorphic markers were retained according to the amplification efficiency and polymorphism.These 35 microsatellite loci were then assessed in 96 individuals in four geographical populations collected from China. The allele numbers ranged from 2 to 19 with an average value of 6.9 per locus, while the polymorphism information content ranged from 0.2219 to 0.8490.The observed and expected heterozygosity varied from 0.5252 to 0.5367 and 0.5934 to 0.6148,respectively. Genetic structure was found between populations from southern and northern China. These novel microsatellite markers developed in our study provide abundant molecular markers for the genetic study of T. palmi.
基金mainly supported by National Science Fund for Distinguished Young Scholars (31625024)a grant (2008DP173354) from the Key Laboratory of the Zoological Systematics and Evolution of the Chinese Academy of Sciences。
文摘Taxonomy plays an important role in understanding the origin, evolution, and ecological functionality of biodiversity. There are large number of unknown species yet to be described by taxonomists, which together with their ecosystem services cannot be effectively protected prior to description. Despite this, taxonomy has been increasingly underrated insufficient funds and permanent positions to retain young talents. Further, the impact factordriven evaluation systems in China exacerbate this downward trend, so alternative evaluation metrics are urgently necessary. When the current generation of outstanding taxonomists retires,there will be too few remaining taxonomists left to train the next generation. In light of these challenges, all co-authors worked together on this paper to analyze the current situation of taxonomy and put out a joint call for immediate actions to advance taxonomy in China.
基金supported by the National Natural Science Foundation of China(31770691)the National Key R&D Program of China(2018YFC1200400)。
文摘The weevils Eucryptorrhynchus brandti(Harold)and E.scrobiculatus(Motschulsky)are two pests of the tree of heaven,Ailanthus altissima.They usually co-occur on their host tree.However,these two species have a niche separation with different eggs-laying locations and larvae-feeding parts on the tree.Here,we characterized the distribution of microsatellites in the genome and developed genome-wide microsatellite markers shared between these two weevils.A total of 12,524 and 11,030 potential microsatellites were identified for E.brandti and E.scrobiculatus,respectively.Microsatellites with AT,TA,AC,TG,CA repeat motifs were most common for both species.We designed primers universal for two weevils and developed 14 loci with high amplification efficacy and polymorphism.We validated these microsatellite markers in three populations of each species.In E.brandti,the observed and expected heterozygosity for the genotyped loci ranged from 0.17-0.24 and 0.44-0.54;in E.scrobiculatus,the above values ranged from 0.06-0.18 and 0.18-0.27.Based on the developed microsatellite markers,we found that populations of both weevils have a clear pattern of genetic differentiation.Our study provides valuable genetic markers for ecological,genetic,and evolutionary study of these two weevils.
基金provided jointly by the National Natural Science Foundation of China(31472025,31101661)973 Program of China(2013CB127600)
文摘The complete mitochondrial genome of the Gasteruption parvicollarium Enderlein （GenBank accession number： KR270643） was sequenced in the study. Totally 17 009 bp sequence was determined with an A＋T content of 83.81%, including full set of typical animal mitochondrial genes. Two protein-coding and 10 tRNA genes as well as the A＋T-rich region were rearranged compared with the putative ancestral arrangement of insects. Most of the rearranged genes were located in the ancestral region of trnl-trnQ-trnM-nad2-trn W-trnC-trn Y- coxl-trnL2. The other rearranged genes are trnN and trnS1 located in the tRNA cluster trnA- trnR-trnN-trnSl-trnE-trnF and trnS2 located between cob and nadl. Remote inversion is dominant rearrangement event in G. parvicollarium mitochondrial genome, involving two protein-coding and 8 tRNA genes. Compared with the other mitochondrial genome reported in the same genus of Gasteruption, the inverted trnN was translocated to the tRNA cluster between cox1 and nad2 in G. parvicollarium. This is the first report of mitochondrial gene rearrangement occurred within genus of Hymenoptera. Our study points to a recently occurred gene rearrangement event in the Gasteruption species.
基金funded by the Natural Science Foundation of Beijing Municipality(6162010)the National Natural Science Foundation of China(31472025)+1 种基金the International Cooperation Fund of Beijing Academy of Agriculture and Forestry Sciences(GJHZ2017)the Beijing Key Laboratory of Environmentally Friendly Pest Management on Northern Fruits(BZ0432)
文摘Double-digested Restriction Site Associated DNA Sequencing（ddRAD） through next-generation sequencing（NGS） generates large numbers of loci for characterizing genomewide variation among multiple samples using next-generation sequencing. Different combinations of restriction endonucleases（REs） may produce varying size distributions of digested fragments, which affect the number of genotyped loci. Understanding digestion profiles across different species will help in selecting REs for digestion in a particular organism. In this study, we use of genome sequences to compare the in silico digestion profile of 26 combinations of REs in 131 insect species with two simulation programs. The number of digested fragments in the 300-450 bp range increases linearly with the size of the genome. Different species and insect orders showed similar profiles when digested by different combinations of REs in silico, indicating the conservation of digestion by double enzymes in insect genomes. Combinations with Nla III or TaqαI usually produced higher number of fragments in the range 300-450 bp, while combinations with EcoRI or MluCI produced fewer fragments. The proportion of fragments with the same overhangs at the two ends of digested DNA was higher than those with different overhangs. The two four-base enzyme pairs produced more fragments in the 300-450 bp range than pairs of four-base ＋ six-base enzymes. Experimental digestion of three species from Hymenoptera, Lepidoptera and Thysanoptera showed profiles congruent with in silico expectations. Our results shed light on understanding the digestion profiles of insect genomes and provide guidance on selecting REs for ddRAD projects.
基金supported by the National Natural Science Foundation of China(Grant Number:8217153243).
文摘Mitochondrial DNA(mtDNA)acts as a damage-associated molecular pattern to activate the stimulator of interferon genes(STING)signaling in macrophages,promoting tissue inflammation.However,its role in acute myocardial infarction(AMI)remains unclear.Macrophage-specific Sting1 knockout mice were used to validate STING’s pathological role in AMI.Cardiac and liver mtDNA were used to activate macrophages in co-culture systems with cardiomyocytes to assess fibrosis and hypertrophy.Panaxatriol saponin(PTS)was tested for its ability to block mtDNA-driven macrophage activation and subsequent cardiomyocyte damage.STING-PTS binding ability was analyzed.AMI rats received PTS to evaluate its effects on myocardial inflammation and ventricular remodeling.In vivo,macrophage-specific Sting1 knockout reduced myocardial inflammation and injury after AMI.In vitro,mtDNA-activated macrophages induced cardiomyocyte fibrosis and hypertrophy through STING signaling.PTS suppressed mtDNA-driven macrophage activation by directly binding STING,thereby blocking inflammatory cascades.In AMI rats,PTS treatment attenuated acute inflammation and reversed ventricular remodeling.These findings establish the mtDNA-STING axis in macrophages as a critical driver of post-AMI inflammation and identify pharmacological STING inhibition with PTS as a promising therapeutic strategy.The study bridges genetic validation with translational applications,highlighting macrophage STING as a novel target for ischemic heart disease management.
基金Supported by the National Natural Science Foundation of China(Grant No.12175249).
文摘Purpose Future large high-luminosity electron–positron colliders such as circular electron positron collider(CEPC)and future circular collider(FCC-ee)require nanometer-sized beams at the interaction point(IP).The luminosity is very sensitive to the beam orbit drifts at the IP.It is essential to have a fast luminosity feedback system at the IP to maintain optimum beam collision conditions and prevent a luminosity degradation due to orbit drifts in the presence of mechanical vibrations and dynamical imperfections.Methods We considered two possible methods for this purpose for CEPC:one based on measurements of the luminosity and the other based on measurements of the beam orbits around the IP.Results In this paper,we present the preliminary design consideration for a fast luminosity feedback system at the IP of CEPC.
文摘Correction to:Radiation Detection Technology and Methods(2024)8:1-1105.https://doi.org/10.1007/s41605-024-00463-y.In this article all authors name was missing in the springer link.It has been corrected.The original article has been corrected.
基金the National Natural Science Foundation of China(11805221)the Union Foundation of excellent post-doctoral of China Post-Doctoral Science Foundation and Chinese Science Academy(Y71I21)。
文摘Purpose In order to update the BPM electronic in BEPCII,a high-performance digital BPM processor is designed,and the RF front-end electronic is the key part in the digital BPM processor system.Methods According to the BEPCII physical parameters andADCunder-sampling theorem,the low-noise and high-dynamicrange RF front-end electronic module is designed.This article will introduce filter,RF amplifier,isolation,system test,etc.Results and conclusions The experimental results showed that BPM position short-term resolution is better than 100 nm,and long-term resolution is better than 5μm.It is the first domestic BPM processor that runs stably in the storage ring accelerator for a long time.Meanwhile,the study can help us to establish a solid foundation for the next work of BPM electronics development.
基金support from diverse funding sources,including the National Key Program for S&T Research and Development of the Ministry of Science and Technology(MOST),Yifang Wang's Science Studio of the Ten Thousand Talents Project,the CAS Key Foreign Cooperation Grant,the National Natural Science Foundation of China(NSFC)Beijing Municipal Science&Technology Commission,the CAS Focused Science Grant,the IHEP Innovation Grant,the CAS Lead Special Training Programthe CAS Center for Excellence in Particle Physics,the CAS International Partnership Program,and the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international partners.The complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs factory.In its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs bosons.Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of magnitude.This Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering aspects.Additionally,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection procedures.Construction is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 years.The commencement of experiments and data collection could potentially be initiated in the mid-2030s.
基金funded by the Youth Innovation Promotion Association CAS(Nos.2019013 and Y202005)the National Natural Science Foundation of China(No.11975254).
文摘Purpose Based on the requirements of the High Energy Photon Source(HEPS),the key components for strip-type and button-type beam position monitors(BPMs)and feedthroughs are designed and manufactured.Method The mechanical structure of the feedthroughs is designed according to the Computer Simulation Technology(CST)simulation results.Resultsandconclusions Small batches of feedthroughs are manufactured,and the structure is optimized based on mechanical,vacuum,electromagnetic,and other characteristic test results.The performance improved significantly owing to optimization through batch product testing,and quality control-related information from several manufacturers is obtained,which provide a foundation for the development of BPMs for HEPS.
基金funded by the Foundation ofYouth Innovation Promotion Association,CAS(No.Y202005)the Major achievements cultivation project of major scientific and technological infrastructure,CAS(No.NE01G74Y2)the National Natural Science Foundation of China(No.11805221).
文摘Purpose Hundreds of digital beam position monitor processors(DBPM)are required to be produced during the construction of projects such as High Energy Photon Source(HEPS)and the upgrade project of the Beijing Electron Positron Collider(BEPCII),which brings great challenges to the test work.In order to achieve accurate,fast,and complete mass production tests of DBPMs,an automatic test system(ATS)has been developed in this article.Methods According to the test items of DBPM,the standardized testing softwareflow is designed based on virtual instru-ment program control technology and experimental physics and industrial control system(EPICS),which realize automatic adjustment of test parameters and automatic acquisition of test result data.Results and conclusions The ATS can realize one-button testing of channel coefficients,channel linearity,attenuator linearity,beam current dependence(BCD)and sampling signal-to-noise ratio(SNR),and generate test reports.The total test time is less than 3 minutes,which is significantly more efficient compared to manual testing.More than 90 BEPCII DBPMs has been tested by this ATS in the lab.The test results proved that such a system could automatically recognize defective products and satisfy the requirements of mass testing.
文摘Background The current strategy to achieve high luminosity for high energy physics experiments is to store huge currents distributed in many bunches in circular machines such as BEPCII,so the longitudinal coupled bunch instabilities of the beam are inevitable.Purpose Therefore,a longitudinal feedback system is needed to suppress longitudinal oscillation.Otherwise,the beam energy spread will increase;the luminosity and the beam lifetime will decrease under a certain beam current.Methods For filter design of the feedback system,the time domain least square fitting(TDLSF)method is compared to the selective wave filter method;digital signal processing electronics based on commercial board have been developed and tested on BEPCII.Results The final result shows that the self-developed longitudinal feedback system can suppress the longitudinal beam oscillation at 750 mA beam current and meet the requirements of BEPCII;the restrain depth to the sidebands reaches to 40.8 dB.
