Objective:Reconstruction of the digestive tract for adenocarcinoma of esophagogastric junction(AEG)is in dispute.This study evaluated Cheng’s gastric tube interposition esophagogastrostomy with reconstruction of His ...Objective:Reconstruction of the digestive tract for adenocarcinoma of esophagogastric junction(AEG)is in dispute.This study evaluated Cheng’s gastric tube interposition esophagogastrostomy with reconstruction of His angle and fundus(Cheng’s GIRAFFE anastomosis)in laparoscopic/open proximal gastrectomy for Siewert typeⅡAEG,which was performed at Zhejiang Cancer Hospital and the First Affiliated Hospital of Zhejiang Chinese Medical University.Here,we discuss the preliminary results of gastric emptying and anti-reflux.Methods:From a retrospective database,74 patients with advanced Siewert typeⅡAEG underwent curative proximal gastrectomy with GIRAFFE anastomosis,and their gastric emptying and anti-reflux outcomes were evaluated by the Reflux Disease Questionnaire(RDQ)score,nuclide gastric emptying,24-h impedance-pH monitoring and gastroscopy.Results:Seventy-four patients successfully completed proximal partial gastrectomy with Cheng’s GIRAFFE esophagogastric anastomosis.RDQ score six months after the operation was 2.2±2.5.Results of nuclide gastric emptying examinations showed that the gastric half-emptying time was 67.0±21.5 min,the 1-h residual rate was(52.2±7.7)%,the 2-h residual rate was(36.4±5.1)%,and the 3-h residual rate was(28.8±3.6)%;24-h impedance-p H monitoring revealed that the mean De Meester score was 5.8±2.9.Reflux esophagitis was observed by gastroscopy in 7 patients six months after surgery.Conclusions:Cheng’s GIRAFFE anastomosis is safe and feasible for Siewert typeⅡAEG.展开更多
A 48-year-old female patient was diagnosed with a superficial depressed type early gastric cancer （type IIc） of 1.0 cm at the gastric angle as indicated by gastroscopy. Laparoscopic-assisted greater omentumpreservin...A 48-year-old female patient was diagnosed with a superficial depressed type early gastric cancer （type IIc） of 1.0 cm at the gastric angle as indicated by gastroscopy. Laparoscopic-assisted greater omentumpreserving D2 radical gastrectomy was performed in combination with Billroth I reconstruction under general anesthesia for the distal gastric cancer on April 5, 2013. The postoperative recovery was satisfying without complications. The patient was discharged seven days after surgery.展开更多
A patient with advanced gastric cancer complicated with pyloric obstruction was treated using D2 ＋ radical resection combined with perioperative chemotherapy, and had satisfying outcomes. The perioperative chemothera...A patient with advanced gastric cancer complicated with pyloric obstruction was treated using D2 ＋ radical resection combined with perioperative chemotherapy, and had satisfying outcomes. The perioperative chemotherapy regimen was Taxol and S1 （tegafur, gimeracil, and oteracil）. Three cycles of neoadjuvant chemotherapy were delivered before surgery, and three cycles of adjuvant therapy after surgery. PR was achieved after chemotherapy. D2 ＋ dissection of stations 8p, 12b, 12p, 13 and 14v lymph nodes was performed on September 10, 2012.展开更多
The hormone gibberellin(GA) plays an important role in modulating diverse processes throughout plant development.Gibberellin(GA) perception is mediated by GID1(GA-INSENSITIVE DWARF1),a receptor that shows similarity t...The hormone gibberellin(GA) plays an important role in modulating diverse processes throughout plant development.Gibberellin(GA) perception is mediated by GID1(GA-INSENSITIVE DWARF1),a receptor that shows similarity to hormone-sensitive lipases.It has been postulated that plants have two types of GA receptors,including soluble and membrane-bound forms.In recent years,significant advances have been made in the research of Gibberellin Receptor(GID1).This article highlights recent advances in the molecular structure of Gibberellin Receptor(GID1),Molecular Interactions between the Gibberellin Receptor(GID1) with DELLA,Cloning and expression of GA receptors(GID1),function identification of GA receptor gene(GID1).These discoveries open new prospects for the understanding mechanism of GA receptors(GID1) in plants.展开更多
Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix...Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while stalk weight per stool and brix weight per stool were measured only in plant cane. Genetic variation and genetic parameters of all traits were analyzed, and the families were evaluated based on comprehensive index method. The results showed that the stalk height of both plant and ratoon, stalk diameter of both plant and ratoon, stalk number per stool of plant, brix of both plant and ratoon, stalk weight per stool and brix weight per stool were sig- nificantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop showed higher level of broad-sense heritability, genetic variation coefficient and relative genetic advance than those in ratoon crop. But there were no significant differences in broad-sense heritability, genetic variation coefficient and relative genetic advance of brix between plant and ratoon crops. Analysis of phenotypic and genotypic correlation showed that stalk weight per stool was significantly correlated with brix weight per stool, Fifteen elite families including Zhanzhe 74-141× CP72-1210, Guitang 05-3081×Yuetang 91-976, Yunzhe 02-588×ROC22, Funong 39× Guitang 03-1229, Guitang 02-901×Guitang 03-2357, Guitang 05-2743×Guitang 03- 1229, Guitang 92-66×ROC22, Dezhe 93-88×ROC22, Guitang 05-3445×Guitang 03- 2309, Yuetang 00-319×CP72-1210, Guitang 03-3089×ROC22, Yuetang 91-976×CP84- 1198, Yuefu 90-95 ×CP72-1210, Yunzhe 99-601×Guitang 00-122, Yuetang 00-236× ROC22 were selected based on comprehensive index method, and stalk weight per stool and brix weight per stool showed greater genetic gain. The families selected based on comprehensive index were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of the families selected based on comprehensive index and brix weight per stool was 0.748 （P〈0.01）.展开更多
In this study,we performed an inter-laboratory collaborative ring trial to develop and validate specific TaqMan real-time PCR assays for goat-,horse-,and donkey-derived material in meat products.The performances of th...In this study,we performed an inter-laboratory collaborative ring trial to develop and validate specific TaqMan real-time PCR assays for goat-,horse-,and donkey-derived material in meat products.The performances of these assays in different environments and situations were comprehensively evaluated.This ring trial involved the participation of 12 laboratories in Europe and Asia.The results from the participating laboratories were analyzed to determine the specificity,accuracy,false positive rate,limit of detection(LOD),and probability of detection(POD)of the developed assays.Statistical analysis showed that the false positive and negative rates were zero,the LOD was five copies/reaction,and the laboratory standard deviation(σ_(L))was 0.30 for all three assays.Thus,the results demonstrate that the developed methods are robust and suitable for the detection and identification of goat-,horse-,and donkey-derived materials in meat products.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
Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχf...Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.展开更多
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire...Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.展开更多
A study on cosmogenic activation in germanium was carried out to evaluate the cosmogenic background level of natural and ^(70)Ge depleted germanium detectors. The production rates of long-lived radionuclides were calc...A study on cosmogenic activation in germanium was carried out to evaluate the cosmogenic background level of natural and ^(70)Ge depleted germanium detectors. The production rates of long-lived radionuclides were calculated with Geant4 and CRY.Results were validated by comparing the simulated and experimental spectra of CDEX-1B detector. Based on the validated codes, the cosmogenic background level was predicted for further tonne-scale CDEX experiment. The suppression of cosmogenic background level could be achieved by underground germanium crystal growth and high-purity germanium detector fabrication to reach the sensitivity requirement for direct detection of dark matter. With the low cosmogenic background, new physics channels,such as solar neutrino research and neutrinoless double-beta decay experiments, were opened and the corresponding simulations and evaluations were carried out.展开更多
We report the first results on 76Ge neutrinoless double beta decay from stage one of the China dark-matter experiment （CDEX）. A p-type point-contact high-purity germanium detector with a mass of 994g has been instal...We report the first results on 76Ge neutrinoless double beta decay from stage one of the China dark-matter experiment （CDEX）. A p-type point-contact high-purity germanium detector with a mass of 994g has been installed to detect neutrinoless double beta decay events, as well as to directly detect dark matter particles. An exposure of 304kgd has been analyzed over a wide spectral band from 500keV to 3MeV. The average event rate obtained was about 0.012 counts per keV per kg per day over the 2.039MeV energy range. The half-life of76Ge neutrinoless double beta decay derived based on this result is 70v2〉6.4× 1022 yr （90%C.L.）. An upper limit on the effective Majorana-neutrino mass of 5.0eV has been achieved.展开更多
We present weakly interacting massive particles(WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment(CDEX), based on the data from both CDEX-1B and CDEX-...We present weakly interacting massive particles(WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment(CDEX), based on the data from both CDEX-1B and CDEX-10 stages. In the nonrelativistic effective field theory approach, both time-integrated and annual modulation analyses were used to set new limits for the coupling of WIMP-nucleon effective operators at 90% confidence level(C.L.) and improve over the current bounds in the low mχregion. In the chiral effective field theory approach, data from CDEX-10 were used to set an upper limit on WIMP-pion coupling at 90% C.L. We for the first time extended the limit to the m_(χ)<6 GeV/c^(2) region.展开更多
The CDEX-10 experiment searches for light weakly interacting massive particles, a form of dark matter, at the China Jinping Underground Laboratory, where approximately 10 kg of germanium detectors are arranged in an a...The CDEX-10 experiment searches for light weakly interacting massive particles, a form of dark matter, at the China Jinping Underground Laboratory, where approximately 10 kg of germanium detectors are arranged in an array and immersed in liquid nitrogen. Herein, we report on the experimental apparatus, detector characterization, and spectrum analysis of one prototype detector. Owing to the higher rise-time resolution of the CDEX-10 prototype detector as compared with CDEX-1 B, we identified the origin of an observed category of extremely fast events. For data analysis of the CDEX-10 prototype detector, we introduced and applied an improved bulk/surface event discrimination method. The results of the new method were compared to those of the CDEX-1 B spectrum. Both sets of results showed good consistency in the 0-12 ke Vee energy range, except for the 8.0 keV K-shell X-ray peak from the external copper.展开更多
基金Diagnosis and Therapy Center of Upper Gastrointestinal Tumor(No.JBZX202006)Key Laboratory of Prevention,Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang Province(No.2022E10021)Medical Health Plan of Zhejiang Province(No.2020KY488 and No.2022KY684)。
文摘Objective:Reconstruction of the digestive tract for adenocarcinoma of esophagogastric junction(AEG)is in dispute.This study evaluated Cheng’s gastric tube interposition esophagogastrostomy with reconstruction of His angle and fundus(Cheng’s GIRAFFE anastomosis)in laparoscopic/open proximal gastrectomy for Siewert typeⅡAEG,which was performed at Zhejiang Cancer Hospital and the First Affiliated Hospital of Zhejiang Chinese Medical University.Here,we discuss the preliminary results of gastric emptying and anti-reflux.Methods:From a retrospective database,74 patients with advanced Siewert typeⅡAEG underwent curative proximal gastrectomy with GIRAFFE anastomosis,and their gastric emptying and anti-reflux outcomes were evaluated by the Reflux Disease Questionnaire(RDQ)score,nuclide gastric emptying,24-h impedance-pH monitoring and gastroscopy.Results:Seventy-four patients successfully completed proximal partial gastrectomy with Cheng’s GIRAFFE esophagogastric anastomosis.RDQ score six months after the operation was 2.2±2.5.Results of nuclide gastric emptying examinations showed that the gastric half-emptying time was 67.0±21.5 min,the 1-h residual rate was(52.2±7.7)%,the 2-h residual rate was(36.4±5.1)%,and the 3-h residual rate was(28.8±3.6)%;24-h impedance-p H monitoring revealed that the mean De Meester score was 5.8±2.9.Reflux esophagitis was observed by gastroscopy in 7 patients six months after surgery.Conclusions:Cheng’s GIRAFFE anastomosis is safe and feasible for Siewert typeⅡAEG.
文摘A 48-year-old female patient was diagnosed with a superficial depressed type early gastric cancer （type IIc） of 1.0 cm at the gastric angle as indicated by gastroscopy. Laparoscopic-assisted greater omentumpreserving D2 radical gastrectomy was performed in combination with Billroth I reconstruction under general anesthesia for the distal gastric cancer on April 5, 2013. The postoperative recovery was satisfying without complications. The patient was discharged seven days after surgery.
文摘A patient with advanced gastric cancer complicated with pyloric obstruction was treated using D2 ＋ radical resection combined with perioperative chemotherapy, and had satisfying outcomes. The perioperative chemotherapy regimen was Taxol and S1 （tegafur, gimeracil, and oteracil）. Three cycles of neoadjuvant chemotherapy were delivered before surgery, and three cycles of adjuvant therapy after surgery. PR was achieved after chemotherapy. D2 ＋ dissection of stations 8p, 12b, 12p, 13 and 14v lymph nodes was performed on September 10, 2012.
基金Supported by Natural Science Foundation of China(31360312)Guangxi Natural Science Foundation(2015GXNSFDA39011)+6 种基金National High Technology Research and Development Program("863"Program)of China(2013AA102604)National Key Technology R&D Program(2012BAD40B04-3)Guangxi Natural Science Foundation(2014GXNSFBA118087)International Scientific Cooperation Program of China(2013DFA31600)Guangxi Special Fund for Bagui Scholars(2013)Guangxi Academy of Agricultural Sciences project(2014YP03,2014YD02,2015YM13,2015YT03)Guangxi Academy of Agricultural Sciences Project(2014YP03,2014YD02,2015YM13,2015YT03)
文摘The hormone gibberellin(GA) plays an important role in modulating diverse processes throughout plant development.Gibberellin(GA) perception is mediated by GID1(GA-INSENSITIVE DWARF1),a receptor that shows similarity to hormone-sensitive lipases.It has been postulated that plants have two types of GA receptors,including soluble and membrane-bound forms.In recent years,significant advances have been made in the research of Gibberellin Receptor(GID1).This article highlights recent advances in the molecular structure of Gibberellin Receptor(GID1),Molecular Interactions between the Gibberellin Receptor(GID1) with DELLA,Cloning and expression of GA receptors(GID1),function identification of GA receptor gene(GID1).These discoveries open new prospects for the understanding mechanism of GA receptors(GID1) in plants.
基金Supported by Special Fund for Sugarcane Industry Technology System Construction(CARS-20-1-3)Scientific Research and Technological Development Program of Guangxi Zhuang Autonomous Region(1598006-1-1A)+3 种基金Special Fund for Sugarcane Breeding Program of Guangxi Zhuang Autonomous RegionSpecial Fund for Basic Scientific Research of Guangxi Academy of Agricultural Sciences(2014YZ02,2015JZ01,2015JZ02,2016YM03)Science and Technology Development Foundation of Guangxi Academy of Agricultural Sciences(2015JM05)Scientific and Technological Achievements Transformation Project of Guangxi Academy of Agricultural Sciences(2016001)~~
文摘Sugarcane family evaluation on 108 hybridized combinations generated during 2013-2014 was conducted by measuring the main traits of plant and ratoon crops. Stalk height, stalk diameter, stalk number per stool and brix were investigated in both plant cane and ratoon cane, while stalk weight per stool and brix weight per stool were measured only in plant cane. Genetic variation and genetic parameters of all traits were analyzed, and the families were evaluated based on comprehensive index method. The results showed that the stalk height of both plant and ratoon, stalk diameter of both plant and ratoon, stalk number per stool of plant, brix of both plant and ratoon, stalk weight per stool and brix weight per stool were sig- nificantly different among the families. Stalk height, stalk diameter, stalk number per stool of plant crop showed higher level of broad-sense heritability, genetic variation coefficient and relative genetic advance than those in ratoon crop. But there were no significant differences in broad-sense heritability, genetic variation coefficient and relative genetic advance of brix between plant and ratoon crops. Analysis of phenotypic and genotypic correlation showed that stalk weight per stool was significantly correlated with brix weight per stool, Fifteen elite families including Zhanzhe 74-141× CP72-1210, Guitang 05-3081×Yuetang 91-976, Yunzhe 02-588×ROC22, Funong 39× Guitang 03-1229, Guitang 02-901×Guitang 03-2357, Guitang 05-2743×Guitang 03- 1229, Guitang 92-66×ROC22, Dezhe 93-88×ROC22, Guitang 05-3445×Guitang 03- 2309, Yuetang 00-319×CP72-1210, Guitang 03-3089×ROC22, Yuetang 91-976×CP84- 1198, Yuefu 90-95 ×CP72-1210, Yunzhe 99-601×Guitang 00-122, Yuetang 00-236× ROC22 were selected based on comprehensive index method, and stalk weight per stool and brix weight per stool showed greater genetic gain. The families selected based on comprehensive index were not completely the same as the families selected by brix weight per stool, the rank correlation coefficient of the families selected based on comprehensive index and brix weight per stool was 0.748 （P〈0.01）.
基金National Key Research and Development Program of China(2017YFC1601700)Shanghai Science and Technology Commission Standard Special Fund(19DZ2205000)Shanghai Science and Technology Commission Technology Platform Research Fund(20DZ2291900).
文摘In this study,we performed an inter-laboratory collaborative ring trial to develop and validate specific TaqMan real-time PCR assays for goat-,horse-,and donkey-derived material in meat products.The performances of these assays in different environments and situations were comprehensively evaluated.This ring trial involved the participation of 12 laboratories in Europe and Asia.The results from the participating laboratories were analyzed to determine the specificity,accuracy,false positive rate,limit of detection(LOD),and probability of detection(POD)of the developed assays.Statistical analysis showed that the false positive and negative rates were zero,the LOD was five copies/reaction,and the laboratory standard deviation(σ_(L))was 0.30 for all three assays.Thus,the results demonstrate that the developed methods are robust and suitable for the detection and identification of goat-,horse-,and donkey-derived materials in meat products.
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supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1607100,and 2022YFA1605000)the National Natural Science Foundation of China(Grant Nos.12322511,12175112,12005111,and 11725522)。
文摘Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.
基金supported by the National Natural Science Foundation of China(Grant Nos.11490560 and 11321064)the National Basic Research Program of China(Grant No.2013CB834406)
文摘Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.
基金supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0402200,and 2017YFA0402201)the National Science Fund for Distinguished Young Scholars(Grant No.11725522)+2 种基金the National Natural Science Foundation of China(Grant Nos.11475092,11475099,and 11675088)the National Basic Research Program of China(Grant No.2010CB833006)the Tsinghua University Initiative Scientific Research Program(Grant No.20151080354)
文摘A study on cosmogenic activation in germanium was carried out to evaluate the cosmogenic background level of natural and ^(70)Ge depleted germanium detectors. The production rates of long-lived radionuclides were calculated with Geant4 and CRY.Results were validated by comparing the simulated and experimental spectra of CDEX-1B detector. Based on the validated codes, the cosmogenic background level was predicted for further tonne-scale CDEX experiment. The suppression of cosmogenic background level could be achieved by underground germanium crystal growth and high-purity germanium detector fabrication to reach the sensitivity requirement for direct detection of dark matter. With the low cosmogenic background, new physics channels,such as solar neutrino research and neutrinoless double-beta decay experiments, were opened and the corresponding simulations and evaluations were carried out.
基金supported by the National Natural Science Foundation of China(Grant Nos.11275107,11475117,11475099,and 11675088)the National Key Basic Research Program of China(Grant No.2010CB833006)
文摘We report the first results on 76Ge neutrinoless double beta decay from stage one of the China dark-matter experiment （CDEX）. A p-type point-contact high-purity germanium detector with a mass of 994g has been installed to detect neutrinoless double beta decay events, as well as to directly detect dark matter particles. An exposure of 304kgd has been analyzed over a wide spectral band from 500keV to 3MeV. The average event rate obtained was about 0.012 counts per keV per kg per day over the 2.039MeV energy range. The half-life of76Ge neutrinoless double beta decay derived based on this result is 70v2〉6.4× 1022 yr （90%C.L.）. An upper limit on the effective Majorana-neutrino mass of 5.0eV has been achieved.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0402200)the National Natural Science Foundation of China(Grant Nos.11725522,11675088,11475099U1865205)。
文摘We present weakly interacting massive particles(WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment(CDEX), based on the data from both CDEX-1B and CDEX-10 stages. In the nonrelativistic effective field theory approach, both time-integrated and annual modulation analyses were used to set new limits for the coupling of WIMP-nucleon effective operators at 90% confidence level(C.L.) and improve over the current bounds in the low mχregion. In the chiral effective field theory approach, data from CDEX-10 were used to set an upper limit on WIMP-pion coupling at 90% C.L. We for the first time extended the limit to the m_(χ)<6 GeV/c^(2) region.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0402201)the National Natural Science Foundation of China(Grant Nos.11475092,11475099,11675088,and 11725522)
文摘The CDEX-10 experiment searches for light weakly interacting massive particles, a form of dark matter, at the China Jinping Underground Laboratory, where approximately 10 kg of germanium detectors are arranged in an array and immersed in liquid nitrogen. Herein, we report on the experimental apparatus, detector characterization, and spectrum analysis of one prototype detector. Owing to the higher rise-time resolution of the CDEX-10 prototype detector as compared with CDEX-1 B, we identified the origin of an observed category of extremely fast events. For data analysis of the CDEX-10 prototype detector, we introduced and applied an improved bulk/surface event discrimination method. The results of the new method were compared to those of the CDEX-1 B spectrum. Both sets of results showed good consistency in the 0-12 ke Vee energy range, except for the 8.0 keV K-shell X-ray peak from the external copper.
