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Journal of Semiconductors 2014年第1期35卷 1-6页

作者： n.sahoo T.Sahu Department of Electronic Science Berhampur University Department of Electronics and Communication Engineering National Institute of Science and Technology

We study the multisubband electron mobility in a barrier delta doped AlχGal-χAs parabolic quantum well structure under the influence of an applied electric field perpendicular to the interface plane. We consider the alloy fraction χ = 0.3 for barriers and vary x from 0.0 to 0.1 for the parabolic well. Electrons diffuse into the well and confine within the triangular like potentials near the interfaces due to Coulomb interaction with ionized donors. The parabolic structure potential, being opposite in nature, partly compensates the Coulomb potential. The external electric field further amends the potential structure leading to an asymmetric potential profile. Accordingly the energy levels, wave functions and occupation of subbands change. We calculate low temperature electron mobility as a function of the electric field and show that when two subbands are occupied, the mobility is mostly dominated by ionised impurity scattering mediated by intersubband effects. As the field increases transition from double subband to single subband occupancy occurs. A sudden enhancement in mobility is obtained due to curtailment of intersubband effects. Thereafter the mobility is governed by both impurity and alloy disorder scatterings. Our analysis of mobility as a function of the electric field for different structural parameters shows interesting results.

关键词： parabolic quantum well multisubband electron mobility AlGaAs

激波管变形AA5052-H32板材的成形性（英文）

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Transactions of nonferrous Metals Society of China 2020年第3期30卷 603-618页

作者： S.K.BARIK R.G.nARAYAnAn n.sahoo Department of Mechanical Engineering Indian Institute of Technology Guwahati

采用激波管研究弯曲预应变和压力对AA5052-H32板材成形行为的影响。测量变形拱形高度、有效应变和应力分布、硬度和晶粒尺寸演变等各种成形参数。在板材上印制圆形网格,并用Hill’s 1948屈服准则计算有效应变分布,通过Hollomon幂次定律... 详细信息

采用激波管研究弯曲预应变和压力对AA5052-H32板材成形行为的影响。测量变形拱形高度、有效应变和应力分布、硬度和晶粒尺寸演变等各种成形参数。在板材上印制圆形网格,并用Hill’s 1948屈服准则计算有效应变分布,通过Hollomon幂次定律计算有效应力分布。在板材的中间位置安装一应变片以监测成形过程中应变的演化。应变-时间图证实峰值应变的急剧上升,并在较高的压力下显著增加。成形参数的变化证实材料在没有应变局部化的情况下被均匀拉伸。光学显微组织显示等轴晶在冲击变形后被延展和拉长。因此,材料的成形行为既取决于预应变的大小,也取决于压力的变化。

关键词：冲击波冲击弯曲预应力成形性

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CnT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： Ranjeet RAI R.R.sahoo Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental well-being.Both conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant parameters.The L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 software.The experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four levels.The operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(nO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently examined.The utilization of methodologies such as signal-to-noise(S/n) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing emissions.The engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CnT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,respectively.At 25% engine load,1000 r/min,and OPB20CnT100 fuel(A1-B1-C4) CO,smoke,nO,and HC emissions were the lowest.Engine load affects emissions the most.Engine BSFC increased 3.10% and nO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel fuel.This study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant attributes.The outcomes revealed that orange peel biodiesel infused with CnT can replace diesel fuel in an environmentally friendly way.This alternative

关键词： Taguchi-Grey method OPB20CnT100 transesterification S/n ratio GRG HC CO and nO

Palaeodepositional environment,implications of Glossopteris flora,and organic matter characteristics from the Lower Permian,Karo Open Cast Mine,East Bokaro Coalfield,Damodar Basin,India

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Journal of Palaeogeography 2024年第3期13卷 528-546页

作者： Sankar Suresh Kumar Pillai Rose Ann Sebastian Runcie Paul Mathews Srikanta Murthya Anju Saxena Mrutyunjaya sahoo Suraj Kumar Sahu Gulshan Kumar Dhingra Birbal Sahni Institute of Palaeosciences Academy of Scientific and Innovative Research (AcSIR) Department of Geology School of Earth Science SystemsCentral University of Kerala Department of Geology Ravenshaw University Department of Botany Sri Dev Suman Uttarakhand University

The present study deals with the Early Permian floral diversity,palaeoenvironment,palaeoclimate and depositional setting using a multiproxy approach that includes morphotaxonomy,palynology,and organic geochemistry of Karo OCM （Open Cast Mine）,East Bokaro Coalfield,Damodar Gondwana Basin,India.The Permian sediments of Peninsular India are widely regarded as fluvial,along with some marine incursions.The macroplant fossil assemblage exhibits the presence of Glossopteridales,comprising Glossopteris,Gangamopteris,and Vertebraria,as well as Coniferales,which includes noeggerathiopsis.The palynological assemblage encompasses the dominance of the striate bisaccate pollen Faunipollenites sp.and the subdominance of the non-striate bisaccate pollen Scheuringipollenites sp.with glossopterid affinities.The megafloral and palynofloral assemblage confirms the biostratigraphical age to be Late Barakar palynoflora of Kungurian affinity.The studied morphological characteristics,including small to large Glossopteris leaves exhibiting a lanceolate shape,acute apices,and acute cuneate or tapering bases,as well as entire margins with narrower lamina and narrow meshes,suggest the existence of a dense forest with the prevalence of a warm and humid climate during their deposition.The organic geochemical characterization based on functional group and biomarker analyses reveals the diagenetic effects on organic matter.Aliphatic symmetric(～2865-2855 cm-1) and asymmetric stretching (～2930-2910 cm-1) peaks are identifiable in coal samples,whereas they are absent in carbonaceous shale.The A-factor vs.C-factor plot suggests that the kerogen type is type Ⅲ,which can generate mainly gaseous kerogen.The vitrinite reflectance studies （Rrav.1.1%） show increased maturity of the samples,which is supported by the n-alkane distribution pattern and the absence of hopane terpenoids.The Indian floral assemblages in contemporary of southern Gondwana continents reveal a stronger inclination/affinity with the flora of Africa than that of South America,thereby

关键词： Glossopteris Palynomorph FTIR GCMS Gondwana Permian Palaeoclimate

Investigation into machining performance of microstructurally engineered in-situ particle reinforced magnesium matrix composite

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Journal of Magnesium and Alloys 2023年第3期11卷 916-935页

作者： S.K.sahoo B.n.sahoo S.K.Panigrahi Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036India Applied Magnesium Research Group Center of Excellence in Materials and Manufacturing for Futuristic MobilityIndian Institute of Technology MadrasChennai 600036India Department of Mechanical Engineering Sardar Vallabhbhai National Institute of TechnologySurat 395007India

Magnesium and magnesium in-situ composites have significant potential in the application of design and manufacturing for automotive and aerospace industries because of their high specific strength and reduced fuel consumption.But there are many challenges for machining of Mg based alloys and composites because of the high tendency of fire and oxidation.These challenges can be minimized through microstructural engineering.In this present study,the machining performances of AZ91 Mg alloy and in-situ hybrid TiC+TiB_(2)reinforced AZ91 metal matrix composite was investigated.The effectβ-Mg_(17)Al_(12)phases and grain refinement with and without in-situ particles on machinability were studied through microstructural engineering via aging and friction stir processing.The end milling operation was carried out at different cutting speeds ranging from 25 mm/min to 90 mm/min under dry environment by using an AlTin-coated tungsten carbide tool.The optimum cutting speed for machining was found to be 75 mm/min based on the surface roughness values of all conditioned materials.The base material with dendritic microstructure was found to have poor machinability in terms of inadequate surface finish and edge-burrs formation.The combined effect of in-situ TiC+TiB_(2)particles addition and grain refinement enhanced the machining performance of the material with superior surface finish,negligible edge-burr formation and better tool wear resistance.The influence of in-situ TiC+TiB_(2)particles,β-Mg_(17)Al_(12)phases and grain refinement on machining characteristics are explained based on the tool wear mechanisms,chip behavior and machining induced affected zone.

关键词： Magnesium In-situ composite End-milling Tool wear Chip morphology

Progress on Medical Implant:A Review and Prospects

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Journal of Bionic Engineering 2023年第2期20卷 470-494页

作者： Ankur Pandey Swagatadeb sahoo Department of Electronics and Communication Engineering National Institute of Technology JamshedpurJamshedpurJharkhand831014India

Medical implant from different materials such as metals,ceramics,polymers and composites have gained a lot of research attraction due to wide applications in medical industry for treatment,surgical operations and preparing artificial body parts.In this work,we highlight a comprehensive review of medical implant mechanism,various types of implant materials,factors affecting the performance of implant and different characterization techniques.This review provides an overall summary of the state-of-the-art progress on various interesting and promising material-based medical implant.Finally,few new prospects are explained from the established theoretical and experimental results for real-life applications.This study is expected to promote extended interest of scientists and engineers in recent trend of modern biomaterials based medical implant.

关键词： Implant material Biocompatibility Hydroxyapatite Dielectric constant

FSE2R:An Improved Collision-Avoidance-based Energy Efficient Route Selection Protocolin USn

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Computer Systems Science & Engineering 2023年第3期44卷 2225-2242页

作者： Prasant Ku.Dash Lopamudra Hota Madhumita Panda n.Z.Jhanjhi Kshira Sagar sahoo Mehedi Masud Department of Computer Science and Engineering Sambalpur UniversityOdisha768019India Department of Computer Science and Engineering NITRourkelaOdisha769008India Department of Computer Science G.M UniversitySambalpurOdisha768001India School of Computer Science and Engineering SCETaylor’s UniversitySubang Jaya47500Malaysia Department of Computer Science and Engineering SRM UniversityAmaravatiAndhra Pradesh522502India Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia

The 3D Underwater Sensor network(USns)has become the most optimistic medium for tracking and monitoring underwater environment.Energy and collision are two most critical factors in USns for both sparse and dense regions.Due to harsh ocean environment,it is a challenge to design a reliable energy efficient with collision free protocol.Diversity in link qualities may cause collision and frequent communication lead to energy loss;that effects the network performance.To overcome these challenges a novel protocol Forwarder Selection Energy Efficient Routing(FSE2R)is proposed.Our proposal’s key idea is based on computation of node distance from the sink,Residual Energy(RE)of each node and Signal to Interference noise Ratio(SInR).The node distance from sink and RE is computed for reliable forwarder node selection and SInR is used for analysis of collision.The novel proposal compares with existing protocols like H2AB,DEEP,and E2LR to achieve Quality of Service(QoS)in terms of through-put,packet delivery ratio and energy consumption.The comparative analysis shows that FSE2R gives on an average 30%less energy consumption,24.62%better PDR and 48.31%less end-to-end delay compared to other protocols.

关键词： USn energy efficiency collision avoidance MAC SInR

An optimized ion trap geometry to measure quadrupole shifts of ^(171)Yb~＋ clocks

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Chinese Physics B 2016年第11期25卷 230-237页

作者： n Batra B K sahoo S De Academy of Scientific and Innovative Research CSIR-NPL Campus New Delhi India CSIR-national Physical Laboratory Dr. K. S. Krishnan Marg New Delhi 110012 India Theoretical Physics Division Physical Research Laboratory Navrangpura Ahmedabad 380009 India

We propose a new ion-trap geometry to carry out accurate measurements of the quadrupole shifts in the （171）Yb ion.This trap will minimize the quadrupole shift due to the harmonic component of the confining potential by an order of magnitude.This will be useful to reduce the uncertainties in the clock frequency measurements of the 6s 2S（1/2）→4f（13）6s2 2F（7/2）and 6s 2S（1/2）→5d2D（3/2） transitions,from which we can deduce the precise values of the quadrupole moments（0s） of the 4f（13）6s2 2F（7/2） and 5d2D（3/2） states.Moreover,it may be able to affirm the validity of the measured 0 value of the4f（13）6s22F（7/2） state,for which three independent theoretical studies defer almost by one order of magnitude from the measurement.We also calculate 0s using the relativistic coupled-cluster（RCC） method.We use these 0 values to estimate the quadrupole shift that can be measured in our proposed ion trap experiment.

关键词： validity minimize carry clock relativistic precise deduce magnitude expectation spatially

Search for the rare decays 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.Bachmayer J.J.Back A.Bailly-reyre P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista de Souza Leite M.Barbetti R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov 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.Belyaev G.Benane G.Bencivenni E.Ben-Haim A.Berezhnoy *** *** Andres D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko 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.Boldyrev C.S.Bolognani R.Bolzonella n.Bondar F.Borgato S.Borghi M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer 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.Buytaert W.Byczynski 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.Chernyshenko V.Chobanova S.Cholak M.Chrzaszcz A.Chubykin 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 Physics Tsinghua UniversityBeijingChina Institute Of High Energy Physics(IHEP) BeijingChina School of Physics State Key Laboratory of nuclear Physics and Technology Peking UniversityBeijingChina University of Chinese Academy of Sciences BeijingChina Institute of Particle Physics 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.Physikalisches Institut RWTH Aachen UniversityAachenGermany Fakultat Physik Technische Universitat DortmundDortmundGermany Max-Planck-Institut für Kernphysik(MPIK) HeidelbergGermany Physikalisches Institut Ruprecht-Karls-Universitat HeidelbergHeidelbergGermany School of Physics 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 Physics AmsterdamNetherlands nikhef national Institute for Subatomic Physics and VU University Amsterdam AmsterdamNetherlands AGH-University of Science and Technology Faculty of Physics and Applied Computer Scienc

A search for the rare decays 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−1.no 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−decays as normalization channels.The 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,respectively.This 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

Search for the doubly heavy baryons Ωbc~0 and Ξbc~0 decaying to Λc~+π~- and Ξc~+π~-

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Chinese Physics C 2021年第9期45卷 14-25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.Arzymatov E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmayer J.J.Back P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista Leite R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov 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.Belyaev G.Bencivenni E.Ben-Haim A.Berezhnoy *** D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko S.Bhasin J.Bhom L.Bian M.S.Bieker S.Bifani P.Billoir M.Birch F.C.R.Bishop A.Bitadze 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.Boldyrev A.Bondar n.Bondar S.Borghi M.Borisyak M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer 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.Buytaert W.Byczynski 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 V.Chobanova S.Cholak M.Chrzaszcz A.Chubykin 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’Occo J.Dalseno C.D’Amb AGH-University of Science and Technology Faculty of Computer Science Electronics and Telecommunications AGH-University of Science and Technology Faculty of Physics and Applied Computer Science Aix Marseille Univ CNRS/IN2P3 CPPM Budker Institute of nuclear Physics (SB RAS) Cavendish Laboratory University of Cambridge Center for High Energy Physics Tsinghua University Centro Brasileiro de Pesquisas Físicas (CBPF) DS4DS La Salle Universitat Ramon Llull Departamento de Fisica Universidad Nacional de Colombia Department of Physics and Astronomy University of Manchester Department of Physics and Astronomy Uppsala University Department of Physics University of Oxford Department of Physics University of Warwick European Organization for nuclear Research (CERn) Fakult?t Physik Technische Universit?t Dortmund Guangdong Provencial Key Laboratory of nuclear Science Institute of Quantum Matter South China Normal University H.H. Wills Physics Laboratory University of Bristol Hangzhou Institute for Advanced Study UCAS Hanoi University of Science Henryk niewodniczanski Institute of nuclear Physics Polish Academy of Sciences Horia Hulubei national Institute of Physics and nuclear Engineering I.Physikalisches Institut RWTH Aachen University ICCUB Universitat de Barcelona InFn Laboratori nazionali di Frascati InFn Sezione di Bari InFn Sezione di Bologna InFn Sezione di Cagliari InFn Sezione di Ferrara InFn Sezione di Firenze InFn Sezione di Genova InFn Sezione di Milano InFn Sezione di Milano-Bicocca InFn Sezione di Perugia InFn Sezione di Pisa InFn Sezione di Roma La Sapienza InFn Sezione di Roma Tor Vergata Imperial College London Institut für Physik Universit?t Rostock Institute Of High Energy Physics (IHEP) Institute for High Energy Physics nRC Kurchatov Institute (IHEP nRC KI) Institute for nuclear Research of the national Academy of Sciences (KInR) Institute for nuclear Research of the Russian Academy of Sciences (InR RAS) Institute of nuclear Physics Moscow State University (SINP MSU) Institute of Part

The first search for the doubly heavy Ωbc~0 baryon and a search for the Ξbc~0 baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 TeV,corresponding to an integrated luminosity of 5.2 fb-1.The baryons are reconstructed via their decays to ∧c~+π~-andΞc~+π~-.no significant excess is found for invariant masses between 6700 and 7300 MeV/c2,in a rapidity range from2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ωbc~0 andΞbc~0 production cross-section times the branching fraction to ∧c~+π~-(Ξc~+π~-) relative to that of the ∧b~0(Ξb~0) baryon,for different lifetime hypotheses,at 95% confidence level.The upper limits range from 0.5×10-4to 2.5×10-4for theΩbc~0→∧c~+π~-(Ξbc~0→∧c~+π~-) decay,and from 1.4×10-3to 6.9×10-3for the Ωbc~0→Ξc~+π~-(Ξbc~0→Ξc~+π~-) decay,depending on the considered mass and lifetime of the Ωbc~0(Ξbc~0) baryon.

关键词： B physics quarkonium spectroscopy heavy quark production