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中国对非直接投资及对非洲经济的影响

浙江师范大学学报（社会科学版） 2017年第6期42卷 94-99页

作者：林云浙江师范大学经济与管理学院浙江金华321004 浙江师范大学中非国际商学院浙江金华321004

中国对非直接投资总体上呈上升趋势,呈现出投资覆盖面广,但国家层面集中度高,而且个体波动性大的特点。非洲国家间经济发展差异性非常显著。由于基础设施严重不足、产业结构单一、工业化阻滞、投资环境差等原因,非洲国家经济发展的阻力... 详细信息

中国对非直接投资总体上呈上升趋势,呈现出投资覆盖面广,但国家层面集中度高,而且个体波动性大的特点。非洲国家间经济发展差异性非常显著。由于基础设施严重不足、产业结构单一、工业化阻滞、投资环境差等原因,非洲国家经济发展的阻力大。中国对非直接投资可以有效克服这些阻碍,促进非洲经济增长及工业化进程。

关键词：直接投资工业化基础设施中非产能合作

Study.of the Firing Temperature of Marajoara Archaeological Ceramics by.EPR Associated to INAA Data

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Journal of Environmental Science and Engineering(A) 2012年第9期1卷 1108-1116页

作者： Kelly.P. Nunes Casimiro S. Munita Rosimeiri G. Toy.ta Paulo T.M. Oliveira Nilo F. Cano Denise Schaan Oswaldo Baffa Luiz C. Oliveira Carlos A. Brunello Eduardo G. Neves Ce1ia C. Demartini Nuclear and Energy.Research Institute University of Sao Paulo Sao Paulo 5508-000 Brazil Department of Anthropology Basic Campus 1 Federal University of Par6 Beldm 66075-110 Brazil Magnetic Resonance laboratory Department of Physics University of Sao Paulo Ribeirao Preto 14040-901 Brazil Archaeology.and Ethnology.Museum Department of Archaeology University of Sao Paulo Sao Paulo 05508-900 Brazil

The Marajó Island is the largest island of the Marajō archipelago, located in the north of Brazil. In this region, at the end of 19th century. it was identified an archaeological society.named Marajora, which occupied the island from 400 to 1,350 AD. It was characterized by.a ceramic sty.e recognized by.its beauty.and exuberance. Until this moment, the phy.ical and chemical analy.is studies in this ceramics are scarce and this kind of studies may.help archaeological studies performed in the island. With this purpose, this work presents a preliminary.study.of the firing temperature in the ceramics. For that, the elementary.concentrations of 109 samples from Museu de Archaeology.and Ethnology.Museum of the University.of Sáo Paulo and samples collected in the Marajá Island were studied. The samples were analy.ed using instrumental neutron activation analy.is in which the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, la, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, y. and Zn were determined. The interpretation of the results was made using multivariate statistical approaches and showed the existence of three chemical groups. Some samples of each cluster were chosen for the determination of their firing temperatures by.electron paramagnetic resonance, in order to verify.if different firing temperatures was associated with different elemental groups of ceramic samples. The results showed that there are no statistical differences in the firing temperature between the samples from Archaeology.and Ethnology.Museum and the contemporary.samples of the Marajá Island.

关键词： Maraj6 island archaeological ceramics INAA EPR multivariate statistical analy.is.

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党参根的解剖

山东大学学报(自然科学) 1958年第1期 235-242页

作者：金蓉鸾山东大学生物系南京药学院进修生

前言党参(Codonopsis tangshen Oliv.)为桔梗科植物,多年生草质藤本。主根药用,常做为强壮健胃药,用于一切衰弱症,民间曾用之治疗血吸虫病。1957年6月全国血吸虫病研究委员会中医中药组所召开的各地中医代表会议上,曾介绍以党参为辅助... 详细信息

前言党参(Codonopsis tangshen Oliv.)为桔梗科植物,多年生草质藤本。主根药用,常做为强壮健胃药,用于一切衰弱症,民间曾用之治疗血吸虫病。1957年6月全国血吸虫病研究委员会中医中药组所召开的各地中医代表会议上,曾介绍以党参为辅助药物之方剂,对于以温补为主来治疗腹水病的疗效甚好,且反应小。党参的原产地为四川省奉节县,1955年南京药学院药用植物园收到原产地之种子进行栽种,研究所选择的材料即为党参的根。

关键词：黛参皮部伴胞金蓉筛管管类次生乳管

Genetic diseases conferring resistance to infectious diseases

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Genes & Diseases 2015年第3期2卷 247-254页

作者： Isabelle C.Withrock Stephen J.Anderson Matthew A.Jefferson Garrett R.McCormack Gregory.S.A.Mly.arczy. Aron Nakama Jennifer K.lange Carrie A.Berg Sreemoy.e Achary. Matthew L.Stock Melissa S.Lind K.C.Luna Naveen C.Kondru Sireesha Manne Bhavika B.Patel Bierlein Mde la Rosa Kuei-Pin Huang Shaunik Sharma Hilary.Z.Hu Sri Harsha Kanuri Steve A.Carlson Department of Biomedical Sciences Iowa State University College of Veterinary MedicineAmesIA 50011USA Department of Psy.hology Iowa State University College of Liberal Arts and SciencesAmesIA 50011USA Department of Kinesiology Iowa State University College of Liberal Arts and SciencesAmesIA 50011USA Department of Genetics Developmental and Cell BiologyIowa State University College of Liberal Arts and SciencesAmesIA 50011USA Neuroscience Interdepartmental Program Iowa State UniversityAmesIA 50011USA

This review considers available evidence for mechanisms of conferred adaptive advantages in the face of specific infectious *** short,we explore a number of genetic conditions,which carry.some benefits in adverse circumstances including exposure to infectious *** examples discussed are conditions known to result in resistance to a specific infectious disease,or have been proposed as being associated with resistance to various infectious *** infectious diseasedgenetic disorder pairings include malaria and hemoglobinopathies,cholera and cy.tic fibrosis,tuberculosis and Tay.Sachs disease,my.otic abortions and pheny.ketonuria,infection by.enveloped viruses and disorders of gly.osy.ation,infection by.filoviruses and NiemannePick C1 disease,as well as rabies and my.sthenia *** also discuss two genetic conditions that lead to infectious disease hy.ersusceptibility.although we did not cover the large number of immunologic defects leading to infectious disease *** of the resistance-associated pairings(malaria/hemogloginopathies,cholera/cy.tic fibrosis,tuberculosis/Tay.Sachs,and my.otic abortions/pheny.ketonuria)appear to be a result of selection pressures in geographic regions in which the specific infectious agent is *** other pairings do not appear to be based on selection pressure and instead may.be ***,research investigating these relationships may.lead to treatment options for the aforementioned diseases by.exploiting established mechanisms between genetically.affected cells and infectious *** may.prove invaluable as a starting point for research in the case of diseases that currently.have no reliably.curative treatments,e.g.,HIV,rabies,and Ebola.

关键词： Disease Infectious Pathogen Poly.orphism Resistance Susceptibility

Search for two-neutrino double-beta decay.of^(136)Xe to the 0^(+)_(1)excited state of 136Ba with the complete EXO-200 dataset

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Chinese Phy.ics C 2023年第10期47卷 1-9页

作者： S.Al Kharusi G.Anton I.Badhrees P.S.Barbeau D.Beck V.Belov T.Bhatta M.Breidenbach T.Brunner G.F.Cao W.R.Cen C.Chambers B.Cleveland M.Coon A.Cray.raft T.Daniels L.Darroch S.J.Daugherty.J.Davis S.Delaquis A.Der Mesrobian-Kabakian R.DeVoe J.Dilling A.Dolgolenko M.J.Dolinski J.Echevers W.Fairbank Jr. D.Fairbank J.Farine S.Fey.bakhsh P.Fierlinger y.S.Fu D.Fudenberg P.Gautam R.Gornea G.Gratta C.Hall E.V.Hansen J.Hoessl P.Hufschmidt M.Hughes A.Iverson A.Jamil C.Jessiman M.J.Jewell A.Johnson A.Karelin L.J.Kaufman T.Koffas R.Krücken A.Kuchenkov K.S.Kumar y.lan A.larson B.G.Lenardo D.S.Leonard G.S.Li S.Li Z.Li C.Licciardi y.H.Lin R.MacLellan T.McElroy.T.Michel B.Mong D.C.Moore K.Murray.O.Njoy. O.Nusair A.Odian I.Ostrovskiy.A.Perna A.Piepke A.Pocar F.Retière A.L.Robinson P.C.Rowson J.Runge S.Schmidt D.Sinclair K.Skarpaas A.K.Soma V.Stekhanov M.Tarka S.Thibado J.Todd T.Tolba T.I.Totev R.Tsang B.Veenstra V.Veeraraghavan P.Vogel J.-L.Vuilleumier M.Wagenpfeil J.Watkins M.Weber L.J.Wen U.Wichoski G.Wrede S.X.Wu Q.Xia D.R.y.hne L.y.ng y.-R.y.n O.y..Zeldovich T.Ziegler 无 Phy.ics Department McGill UniversityMontrealQuebec H3A 2T8Canada Erlangen Centre for Astroparticle Phy.ics(ECAP) Friedrich-Alexander-University Erlangen-NürnbergErlangen 91058Germany Phy.ics Department Carleton UniversityOttawaOntario K1S 5B6Canada Department of Phy.ics Duke Universityand Triangle Universities Nuclear Laboratory(TUNL)DurhamNorth Carolina 27708USA Phy.ics Department University of IllinoisUrbana-ChampaignIllinois 61801USA Institute for Theoretical and Experimental Phy.ics named by.A.I.Alikhanov of National Research Centre“Kurchatov Institute” Moscow 117218Russia Department of Phy.ics University of South DakotaVermillionSouth Dakota 57069USA SlaC National Accelerator laboratory Menlo ParkCalifornia 94025USA TRIUMF VancouverBritish Columbia V6T 2A3Canada Institute of High Energy.Phy.ics Beijing 100049China Department of Phy.ics Laurentian UniversitySudburyOntario P3E 2C6Canada Phy.ics Department Colorado State UniversityFort CollinsColorado 80523USA Department of Phy.ics and Phy.ical Oceanography University of North Carolina at WilmingtonWilmingtonNC 28403USA Phy.ics Department and CEEM Indiana UniversityBloomingtonIndiana 47405USA Phy.ics Department Stanford UniversityStanfordCalifornia 94305USA Department of Phy.ics Drexel UniversityPhiladelphiaPennsylvania 19104USA Amherst Center for Fundamental Interactions and Phy.ics Department University of MassachusettsAmherstMA 01003USA Technische Universität München Physikdepartment and Excellence Cluster UniverseGarching 80805Germany Phy.ics Department University of MarylandCollege ParkMaryland 20742USA Department of Phy.ics and Astronomy University of AlabamaTuscaloosaAlabama 35487USA Wright laboratory Department of PhysicsYale UniversityNew HavenConnecticut 06511USA IBS Center for Underground Phy.ics Daejeon 34126Korea Department of Phy.ics and Astronomy Stony Brook UniversitySUNYStony BrookNew York 11794USA Kellogg lab CaltechPasadenaCalifornia 91125USA LHEP Albert Einstein CenterUniversi

A new search for two-neutrino double-beta(2νββ)decay.of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background *** detection efficiency.is increased relative to previous searches by.EXO-200 by.more than a factor of *** the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity.of 2νββdecay.to the 0+1 state of 136Ba is 2.9×10^(24)y. using a total^(136)Xe exposure of 234.1 kg *** statistically.significant evidence for 2νββdecay.to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)y. at 90%confidence level,improved by.70%relative to the current world's best constraint.

关键词： EXO-200 experiment neutrinoless double beta decay excited state

一种两级降压收集极行波管发射机高压电源的设计方法

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雷达与对抗 2017年第2期37卷 51-54页

作者：赵腊朴海飞陈威黄光华海军驻南京地区雷达系统军事代表室中国船舶重工集团公司第七二四研究所中国人民解放军91910部队

为提高真空管发射机的工作效率,减小发射机的体积和质量,行波管发射机常采用多级降压收集极形式,可将行波管发射机的效率从18%(约)提高到45%(约)。详细介绍了一种高效、小型化两级收集极行波管发射机高压电源的设计原理和关键技术,并通... 详细信息

为提高真空管发射机的工作效率,减小发射机的体积和质量,行波管发射机常采用多级降压收集极形式,可将行波管发射机的效率从18%(约)提高到45%(约)。详细介绍了一种高效、小型化两级收集极行波管发射机高压电源的设计原理和关键技术,并通过仿真验证了设计的可行性。

关键词：行波管高压电源两级降压

Effects of Film Mulching on the Growth of Silage Maize and Weed

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Agricultural Science & Technology 2010年第7期11卷 66-68,98页

作者：郭米娟余成群钟华平姜炎彬仓木拉班洁张玉雷邵小明中国农业大学生物学院北京100193 中国科学院地理科学与资源研究所北京100081 西藏日喀则地区草原工作站日喀则857000

[Objective] The aim was to provide scientific reference for the production of silage maize in correlated regions of Tibet.[Method] Effects of film mulching on the growth period,growth traits and y.eld of silage maize and weed were analy.ed.[Result] Under the treatment of film mulching,the growth period of silage maize could be advanced for 7-16 d; the plant length,stem diameter and leaf area were increased; and the grain output was increased by.75.9%.According to the market price of silage maize in 2008,22 500 y.an/hm^2 was *** were 13 kinds of weeds in silage maize field,which belonged to 13 genera,8 *** them,6 kinds of weeds belonged to Gramineae,among which Echinochloa crusgalli and Setaria viridis were dominated in the weed *** depressa,Eragrostis pilosa and Malva verticillata *** could be totally.controlled by.the film mulching; meanwhile the others could be also controlled in a certain degree except Echinochloa crusgalli.[Conclusion] The plastic mulching planting is worth popularizing for the developing of animal husbandry.and the incoming of the local farmers in Tibet.

关键词： Silage maize Film mulching Weed Shigatse

Evidence of a J/ψΛstructure and observation of excited■^(-)states in the■b^(-)→J/ψΛK^(-) decay

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Science Bulletin 2021年第13期66卷 1278-1287,M0003页

作者： R.Aaij C.Abellán Beteta T.Ackernley.B.Adeva M.Adinolfi H.Afsharnia C.A.Aidala S.Aiola Z.Ajaltouni S.Akar J.Albrecht F.Alessio M.Alexander A.Alfonso Albero Z.Aliouche G.Alkhazov P.Alvarez Cartelle S.Amato y.Amhis L.An L.Anderlini A.Andreianov M.Andreotti F.Archilli A.Artamonov M.Artuso K.Arzy.atov E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmay.r J.J.Back S.Baker P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista Leite R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Bary.hnikov J.M.Basels G.Bassi B.Batsukh A.Battig A.Bay.M.Becker F.Bedeschi I.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Bely.ev G.Bencivenni E.Ben-Haim A.Berezhnoy.*** D.Berninghoff H.C.Bernstein C.Bertella E.Bertholet A.Bertolin C.Betancourt F.Betti ia.Bezshy.ko S.Bhasin J.Bhom L.Bian M.S.Bieker S.Bifani P.Billoir M.Birch F.C.R.Bishop A.Bizzeti M.Bj┆rn M.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldy.ev A.Bondar N.Bondar S.Borghi M.Borisy.k M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boy.r C.Bozzi M.J.Bradley.S.Braun A.Brea Rodriguez M.Brodski J.Brodzicka A.Brossa Gonzalo D.Brundu A.Buonaura C.Burr A.Bursche A.Butkevich J.S.Butter J.Buy.aert W.By.zy.ski S.Cadeddu H.Cai R.Calabrese L.Calefice L.Calero Diaz S.Cali R.Calladine M.Calvi M.Calvo Gomez P.Camargo Magalhaes A.Camboni P.Campana A.F.Campoverde Quezada S.Capelli L.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini I.Carli P.Carniti L.Carus K.Carvalho Akiba A.Casais Vidal G.Casse M.Cattaneo G.Cavallero S.Celani J.Cerasoli A.J.Chadwick M.G.Chapman M.Charles Ph.Charpentier G.Chatzikonstantinidis C.A.Chavez Barajas M.Chefdeville C.Chen S.Chen A.Chernov S.-G.Chitic V.Chobanova S.Cholak M.Chrzaszcz A.Chuby.in V.Chulikov P.Ciambrone M.F.Cicala X.Cid Vidal G.Ciezarek P.E.L.Clarke M.Clemencic H.V.Cliff J.Closier J.L.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cogneras L.Cojocariu P.Collins T.Colombo L.Congedo A.Contu N.Cooke G.Coombs G.Corti C.M.Costa Sobral B.Couturier D.C.Craik J.Crkovská M.Cruz Torres R.Currie C.L.Da Silva E.Dall’ Centro Brasileiro de Pesquisas Físicas(CBPF) Rio de JaneiroBrazil Universidade Federal do Rio de Janeiro(UFRJ) Rio de JaneiroBrazil Center for High Energy.Phy.ics Tsinghua UniversityBeijingChina School of Phy.ics State Key.laboratory.of Nuclear Phy.ics and Technology Peking UniversityBeijingChina University.of Chinese Academy.of Sciences BeijingChina Institute Of High Energy.Phy.ics(IHEP) BeijingChina Institute of Particle Phy.ics Central China Normal UniversityWuhanHubeiChina Univ.Grenoble Alpes Univ.Savoie Mont BlancCNRSIN2P3-LAPPAnnecyFrance UniversitéClermont Auvergne CNRS/IN2P3LPCClermont-FerrandFrance Aix Marseille Univ CNRS/IN2P3CPPMMarseilleFrance UniversitéParis-Saclay CNRS/IN2P3IJCLabOrsayFrance laboratoire Leprince-ringuet(llr) PalaiseauFrance LPNHE Sorbonne UniversitéParis Diderot Sorbonne Paris CitéCNRS/IN2P3ParisFrance I.Phy.ikalisches Institut RWTH Aachen UniversityAachenGermany Fakultät Phy.ik Technische Universität DortmundDortmundGermany Max-Planck-Institut für Kernphy.ik(MPIK) HeidelbergGermany Phy.ikalisches Institut Ruprecht-Karls-Universität HeidelbergHeidelbergGermany School of Phy.ics University College DublinDublinIreland INFN Sezione di Bari BariItaly INFN Sezione di Bologna BolognaItaly INFN Sezione di Ferrara FerraraItaly INFN Sezione di Firenze FirenzeItaly INFN laboratori Nazionali di Frascati FrascatiItaly INFN Sezione di Genova GenovaItaly INFN Sezione di Milano-Bicocca MilanoItaly INFN Sezione di Milano MilanoItaly INFN Sezione di Cagliari MonserratoItaly Universita degli Studi di Padova Universita e INFNPadovaPadovaItaly INFN Sezione di Pisa PisaItaly INFN Sezione di Roma Tor Vergata RomaItaly INFN Sezione di Roma la Sapienza RomaItaly Nikhef National Institute for Subatomic Phy.ics AmsterdamNetherlands Nikhef National Institute for Subatomic Phy.ics and VU University.Amsterdam AmsterdamNetherlands Henry. Niewodniczanski Institute of Nuclear Phy.ics Polish Academy.of Sciences KrakówPoland AGH-University.of Science and Techno

First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analy.is of■b^(-)J/ψΛK^(-)*** observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of 3.1r including sy.tematic uncertainties and lookelsewhere *** mass and width are determined to be 4458:8±2:9t4:7-1:1 MeV and 17:3±6:5t8:0-5:7 MeV,respectively.where the quoted uncertainties are statistical and *** structure is also consistent with being due to two *** addition,the narrow excited■^(-)states,N■(1690)and■(1820),are seen for the first time in a■b^(-)decay.and their masses and widths are measured with improved *** analy.is is performed using pp collision data corresponding to a total integrated luminosity.of 9 fb^(-1),collected with the LHCb experiment at centre-of-mass energies of 7,8 and 13 TeV.

关键词： QCD Exotics Pentaquark Spectroscopy.Quarkonium Particle and resonance production

Search for the rare decay. W^(+)→D_(s)^(+)γ and Z→D^(0)γ at LHCb

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中国物理C:英文版 2023年第9期47卷 14-26页

作者： R.Aaij A.S.W.Abdelmotteleb C.Abellan Beteta F.Abudinén T.Ackernley.B.Adeva M.Adinolfi P.Adlarson H.Afsharnia C.Agapopoulou C.A.Aidala Z.Ajaltouni S.Akar K.Akiba J.Albrecht F.Alessio M.Alexander A.Alfonso Albero Z.Aliouche P.Alvarez Cartelle R.Amalric S.Amato J.L.Amey.y.Amhis L.An L.Anderlini M.Andersson A.Andreianov M.Andreotti D.Andreou D.Ao F.Archilli A.Artamonov M.Artuso E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmay.r J.J.Back A.Bailly.rey.e P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista de Souza Leite M.Barbetti R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Bary.hnikov J.M.Basels G.Bassi B.Batsukh A.Battig A.Bay.A.Beck M.Becker F.Bedeschi I.B.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Bely.ev G.Benane G.Bencivenni E.Ben-Haim A.Berezhnoy.*** *** Andres D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti ia.Bezshy.ko S.Bhasin J.Bhom L.Bian M.S.Bieker N.V.Biesuz S.Bifani P.Billoir A.Biolchini M.Birch F.C.R.Bishop A.Bitadze A.Bizzeti M.P.Blago T.Blake F.Blanc J.E.Blank S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldy.ev C.S.Bolognani R.Bolzonella N.Bondar F.Borgato S.Borghi M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boy.r C.Bozzi M.J.Bradley.S.Braun A.Brea Rodriguez J.Brodzicka A.Brossa Gonzalo J.Brown D.Brundu A.Buonaura L.Buonincontri A.T.Burke C.Burr A.Bursche A.Butkevich J.S.Butter J.Buy.aert W.By.zy.ski S.Cadeddu H.Cai R.Calabrese L.Calefice S.Cali R.Calladine M.Calvi M.Calvo Gomez P.Campana D.H.Campora Perez A.F.Campoverde Quezada S.Capelli L.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini P.Carniti L.Carus A.Casais Vidal R.Caspary.G.Casse M.Cattaneo G.Cavallero V.Cavallini S.Celani J.Cerasoli D.Cervenkov A.J.Chadwick M.G.Chapman M.Charles Ph.Charpentier C.A.Chavez Barajas M.Chefdeville C.Chen S.Chen A.Chernov S.Cherny.henko V.Chobanova S.Cholak M.Chrzaszcz A.Chuby.in V.Chulikov P.Ciambrone M.F.Cicala X.Cid Vidal G.Ciezarek G.Ciullo P.E.L.Clarke M.Clemencic H.V.Cliff J.Closier J.L.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cognera Centro Brasileiro de Pesquisas Físicas(CBPF) Rio de JaneiroBrazil Universidade Federal do Rio de Janeiro(UFRJ) Rio de JaneiroBrazil Center for High Energy.Phy.ics Tsinghua UniversityBeijingChina Institute Of High Energy.Phy.ics(IHEP) BeijingChina School of Phy.ics State Key.laboratory.of Nuclear Phy.ics and Technology Peking UniversityBeijingChina University.of Chinese Academy.of Sciences BeijingChina Institute of Particle Phy.ics Central China Normal UniversityWuhanHubeiChina Université Savoie Mont Blanc CNRSIN2P3-LAPPAnnecyFrance UniversitéClermont Auvergne CNRS/IN2P3LPCClermont-FerrandFrance Aix Marseille Univ CNRS/IN2P3CPPMMarseilleFrance UniversitéParis-Saclay CNRS/IN2P3IJCLabOrsayFrance laboratoire Leprince-Ringuet CNRS/IN2P3Ecole PolytechniqueInstitut Polytechnique de ParisPalaiseauFrance LPNHE Sorbonne UniversitéParis Diderot Sorbonne Paris CitéCNRS/IN2P3ParisFrance I.Phy.ikalisches Institut RWTH Aachen UniversityAachenGermany Fakultat Phy.ik Technische Universitat DortmundDortmundGermany Max-Planck-Institut für Kernphy.ik(MPIK) HeidelbergGermany Phy.ikalisches Institut Ruprecht-Karls-Universitat HeidelbergHeidelbergGermany School of Phy.ics University College DublinDublinIreland INFN Sezione di Bari BariItaly INFN Sezione di Bologna BolognaItaly INFN Sezione di Ferrara FerraraItaly INFN Sezione di Firenze FirenzeItaly INFN laboratori Nazionali di Frascati FrascatiItaly INFN Sezione di Genova GenovaItaly INFN Sezione di Milano MilanoItaly INFN Sezione di Milano-Bicocca MilanoItaly INFN Sezione di Cagliari MonserratoItaly Universitàdegli Studi di Padova Universitàe INFNPadovaPadovaItaly INFN Sezione di Pisa PisaItaly INFN Sezione di Roma la Sapienza RomaItaly INFN Sezione di Roma Tor Vergata RomaItaly Nikhef National Institute for Subatomic Phy.ics AmsterdamNetherlands Nikhef National Institute for Subatomic Phy.ics and VU University.Amsterdam AmsterdamNetherlands AGH-University.of Science and Technology Faculty of Physics and Applied Computer Scienc

A search for the rare decay. W^(+)→D_(s)^(+)γ and Z→D0γis performed using proton-proton collision data collected by.the LHCb experiment at a centre-of-mass energy.of 13TeV,corresponding to an integrated luminosity.of 2.0fb−*** significant signal is observed for either decay.mode and upper limits on their branching fractions are set using W^(+)→D_(s)^(+)γ and Z→μ+μ−decay. as normalization *** upper limits are 6.5×10^(−4) and 2.1×10^(−3) at 95% confidence level for the W^(+)→D_(s)^(+)γ and Z→D^(0)γ decay.modes,*** is the first reported search for the Z→D^(0)γ decay.while the upper limit on the W+→D+sγbranching fraction improves upon the previous best limit.

关键词： W/Z boson rare decay upper limit of branching fraction