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Insensitivity of a turbulent laser-plasma dynamo to initial conditions

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Matter and Radiation at Extremes 2022年第4期7卷 50-64页

作者： A.F.A.Bott L.Chen P.Tzeferacos C.A.j.Palmer A.R.Bell R.Bingham A.Birkel D.H.Froula j.katz M.W.kunz C.-k.Li H-S.Park R.Petrasso j.S.Ross B.Reville D.Ryu F.H.Séguin T.G.White A.A.Schekochihin D.Q.Lamb G.Gregori Department of Physics University of OxfordOxfordUnited Kingdom Department of Astrophysical Sciences University of PrincetonPrincetonNew Jersey 08544USA Department of Physics and Astronomy University of RochesterRochesterNew York 14627USA Laboratory for Laser Energetics University of RochesterRochesterNew York 14623USA School of Mathematics and Physics Queens University BelfastBelfastUnited Kingdom Rutherford Appleton Laboratory ChiltonDidcotUnited Kingdom Department of Physics University of StrathclydeGlasgowUnited Kingdom Massachusetts Institute of Technology CambridgeMassachusetts 02139USA lawrence Livermore National Laboratory LivermoreCalifornia 94550USA Max-Planck-Institut für kernphysik HeidelbergGermany Department of Physics School of Natural SciencesUNISTUlsanSouth Korea Department of Physics University of NevadaRenoNevada 89557USA Department of Astronomy and Astrophysics University of ChicagoChicagoIllinois 60637USA

It has recently been demonstrated experimentally that a turbulent plasma created by the collision of two inhomogeneous,asymmetric,weakly magnetized,laser-produced plasma jets can generate strong stochastic magnetic fields via the small-scale turbulent dynamo mechanism,provided the magnetic Reynolds number of the plasma is sufficiently *** this paper,we compare such a plasma with one arising from two pre-magnetized plasma jets whose creation is identical save for the addition of a strong external magnetic field imposed by a pulsed magnetic field *** investigate the differences between the two turbulent systems using a Thomson-scattering diagnostic,x-ray selfemission imaging,and proton *** Thomson-scattering spectra and x-ray images suggest that the external magnetic field has a limited effect on the plasma dynamics in the *** the external magnetic field induces collimation of the flows in the colliding plasma jets and although the initial strengths of the magnetic fields arising from the interaction between the colliding jets are significantly larger as a result of the external field,the energies and morphologies of the stochastic magnetic fields post-amplification are *** conclude that,for turbulent laser-plasmas with supercritical magnetic Reynolds numbers,the dynamo-amplified magnetic fields are determined by the turbulent dynamics rather than the seed fields or modest changes in the initial flow dynamics of the plasma,a finding consistent with theoretical expectations and simulations of turbulent dynamos.

关键词： turbulent initial stochastic

Search for electron-antineutrinos associated with gravitational-wave events GW150914,GW151012,GW151226,GW170104,GW170608,GW170814,and GW170817 at Daya Bay

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Chinese Physics C 2021年第5期45卷 190-201页

作者： F.P.An A.B.Balantekin H.R.Band M.Bishai S.Blyth G.F.Cao j.Cao j.F.Chang Y.Chang H.S.Chen S.M.Chen Y.Chen Y.X.Chen j.Cheng Z.k.Cheng j.j.Cherwinka M.C.Chu j.P.Cummings O.Dalager F.S.Deng Y.Y.Ding M.V.Diwan T.Dohnal j.Dove M.Dvorak D.A.Dwyer j.P.Gallo M.Gonchar G.H.Gong H.Gong W.Q.Gu j.Y.Guo L.Guo X.H.Guo Y.H.Guo Z.Guo R.W.Hackenburg S.Hans M.He k.M.Heeger Y.k.Heng A.Higuera Y.k.Hor Y.B.Hsiung B.Z.Hu j.R.Hu T.Hu Z.j.Hu H.X.Huang X.T.Huang Y.B.Huang P.Huber D.E.jaffe k.L.jen X.L.ji X.P.ji R.A.johnson D.jones L.kang S.H.kettell S.kohn M.kramer T.j.Langford j.Lee j.H.C.Lee R.T.Lei R.Leitner j.k.C.Leung F.Li j.j.Li Q.j.Li S.Li S.C.Li W.D.Li X.N.Li X.Q.Li Y.F.Li Z.B.Li H.Liang C.j.Lin G.L.Lin S.Lin j.j.Ling j.M.Link L.Littenberg B.R.Littlejohn j.C.Liu j.L.Liu C.Lu H.Q.Lu j.S.Lu k.B.Luk X.B.Ma X.Y.Ma Y.Q.Ma C.Marshall D.A.Martinez Caicedo k.T.MeDonald R.D.Mckeown Y.Meng j.Napolitano D.Naumov E.Naumova j.P.Ochoa-Ricoux A.OIshevskiy H.-R.Pan j.Park S.Patton j.C.Peng C.S.j.Pun F.Z.Qi M.Qi X.Qian N.Raper j.Ren C.Morales Reveco R.Rosero B.Roskovec X.C.Ruan H.Steiner j.L.Sun T.Tmej k.Treskov W.-H.Tse C.E.Tull B.Viren V.Vorobel C.H.Wang j.Wang M.Wang N.Y.Wang R.G.Wang W.Wang W.Wang X.Wang Y.Wang Y.F.Wang Z.Wang Z.Wang Z.M.Wang H.Y.Wei L.H.Wei L.j.Wen k.Whisnant C.G.White H.L.H.Wong E.Worcester D.R.Wu F.L.Wu Q.Wu W.j.Wu D.M.Xia Z.Q.Xie Z.Z.Xing j.L.Xu T.Xu T.Xue C.G.Yang L.Yang Y.Z.Yang H.F.Yao M.Ye M.Yeh B.L.Young H.Z.Yu Z.Y.Yu B.B.Yue S.Zeng Y.Zeng L.Zhan C.Zhang F.Y.Zhang H.H.Zhang j.W.Zhang Q.M.Zhang X.T.Zhang Y.M.Zhang Y.X.Zhang Y.Y.Zhang Z.j.Zhang Z.P.Zhang Z.Y.Zhang j.Zhao L.Zhou H.L.Zhuang j.H.Zou Instiute of Modern Physics East China University of Science and TechnologyShanghai 200237 University of Wisconsin MadisonWisconsin 53706 Wright Laboratory and Department of Physics Yale UniversityNew HavenConnecticut 06520 Brookhaven National Laboratory UptonNew York 11973 Department of Physics National Taiwan UniversityTaipei Institute of High Energy Physics Beijing 100049 National United University Miao-Li Department of Engineering Physics Tsinghua UniversityBejing 100084 Shenzhen University Shenzhen 518060 Sun Yat-Sen(Zhongshan)University Guangzhou North China Electric Power University Bejjing 102206 Chinese University of Hong kong Hong Kong 999077 Siena College LoudonvilleNew York 12211 Department of Physics and Astronomy University of CaliforniaIrvineCaliformia 92697 University of Science and Technology of China Hefei 230026 Charles University Faculty of Mathematics and PhysicsPrague Department of Physics University of llinois at Urbana-ChampaignUrbanaIlinois 61801 lawrence Berkeley National Laboratory BerkeleyCalifornia 94720 Department of Physics Illinois Institute of TechnologyChicagoIllinois 60616 joint Institute for Nuclear Research DubnaMoscow Region Beijing Normal University Beijing 100875 Department of Nuclear Science and Technology School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049 Department of Physics University of HoustonHoustonTexas 77204 China Institute of Atomic Energy Beijing 102413 Shandong University Jinan 250100 Guangxi University Nanning 530004 Center for Neutrino Physics Virginia TechBlacksburgVirginia 24061 Institute of Physics National Chiao-Tung UniversityHsinchu Department of Physics University of CincinnatiCincinnatiOhio 45221 Department of Physies Collge of Science and TechnologyTemple UniversityPhiladelphiaPennsylvania 19122 Dongguan University of Technology Dongguan 523808 Department of Physics University of CaliforniaBerkeleyCalifornia 94720 Department of Physics The University of Hong KongPokfulamHong Kong 999077 School

The establishment of a possible connection between neutrino emission and gravitational-wave(GW)bursts is important to our understanding of the physical processes that occur when black holes or neutron stars *** the Daya Bay experiment,using the data collected from December 2011 to August 2017,a search was per-formed for electron-antineutrino signals that coincided with detected GW events,including GW150914,GW151012,GW151226,GW170104,GW170608,GW 170814,and GW *** used three time windows of±10,±500,and±1000 s relative to the occurrence of the GW events and a neutrino energy range of 1.8 to 100 MeV to search for correlated neutrino *** detected electron-antineutrino candidates were consistent with the expected background rates for all the three time *** monochromatic spectra,we found upper limits(90%confidence level)of the electron-antineutrino fluence of(1.13-2.44)×10^(11)cm^(-2)at 5 MeV to 8.0×10^(7)cm^(-2)at 100 MeV for the three time w *** the assumption of a Fermi-Dirac spectrum,the upper limits were found to be(5.4-7.0)×10^(9)cm^(2)for the three time windows.

关键词： grav itational waves electron-antineutrinos fluence upper limit

Collective Bands in Neutron-Rich ^(104)Mo Nucleus

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Chinese Physics Letters 2001年第1期18卷 24-26页

作者： YANG Li-Ming ZHU Sheng-jiang LI ke j.H.Hamilton A.V.Ramayya j.k.Hwang X.Q.Zhang ZHU Ling-Yan GAN Cui-Yun M.Sakhaee LONG Gui-Lu XU Rui-Qing HANG Zheng jIANG Zhuo jON Myong-Gil W.C.Ma B.R.S.Babu j.komicki E.F.jones j.D.Cole R.Aryaeinejad M.W.Drigert I.Y.Lee j.O.Rasmussen M.A.Stoyer M.Ter-Akopian A.V.Daniel Department of Physics Tsinghua UniversityBeijing 100084 Department of Physics Vanderbilt UniversityNashvilleTN 37235USA Department of Physics Mississippi State UniversityMS 39762USA Idaho National Engineering Laboratory Idaho FallsID 83415USA lawrence Berkeley National Laboratory BerkeleyCA 94720USA lawrence Livermore National Laboratory LivermoreCA 94550USA joint Institute for Nuclear Research Dubna141980Russia

Levels in the neutron-rich ^(104)Mo nucleus have been investigated by observing promptγ-rays from the spontaneous fission of 252Cf with the Gammasphere detector *** ground-state band,the one-phonon and the two-phononγ-vibrational bands as well as a quasiparticle band have been confirmed and expanded with spin up to 14ħ.Other two side bands probably built on new quasiparticle states are *** possible configurations for the quasiparticle bands are *** of the quasiparticle bands show larger moments of inertia and may have pair-free *** levels of the ground-state band,the one-phononγ-band and the two-phononγ-band calculated from a general collective model are in close agreement with the experimental data.

关键词： bands phonon quasi

An Overview of the Control System for Dose Delivery at the UCSF Dedicated Ocular Proton Beam

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International journal of Medical Physics, Clinical Engineering and Radiation Oncology 2016年第4期5卷 242-262页

作者： Inder k. Daftari kavita k. Mishra Rajinder P. Singh Dan j. Shadoan Theodore L. Phillips Department of Radiation Oncology University of California San Francisco (UCSF) San Francisco CA USA lawrence Berkeley National Laboratory (LBNL) Berkeley CA USA

Since 1978, the University of California San Francisco (UCSF) Ocular Tumor Program has been using particle therapy for treating ocular patients with malignant as well as benign eye disease. Helium ion beams were used initially and were produced by two synchrotron-based systems: first by the 184-inch synchro-cyclotron and later by the Bevalac, at the lawrence Berkeley National Laboratory (LBNL). Since 1994, protons, produced by a cyclotron-based system at the Crocker Nuclear Laboratory (CNL) Eye Treatment Facility (ETF), have been used for this purpose. The CNL cyclotron produces a 67.5 MeV beam, allowing for a uniquely homogeneous beam for eye treatment, without degradation of the beam or manipulation of the beam line. This paper describes, in detail, the control system for beam delivery, as implemented for measuring and delivering the radiation to ocular tumors at CNL. The control system allows for optimal delivery and rapid termination of the irradiation after the desired dose is achieved. In addition, several safeguard systems are discussed, as these are essential for such a system in the event of failure of software, electronics, or other hardware. The QA analysis shows that the total range of the proton beam is 30.7 ± 1.0 mm in water at iso-center. The beam distal penumbra (80% - 20%) is 1.1 mm for a range-modulated beam at a collimator to iso-center distance of 50 mm. Daily QA checks confirm that the range and modulation is within 0.1 mm. The beam flatness and symmetry in a 25 mm diameter beam are ±1% - 2%. Variation in the daily dosimetry system, as compared to standard dosimetry, is within ±3.5%, with a mean variation of 0.72(±1.9)% and 0.85(±2.3)% for segmented transmission ionization chambers IC1 (upstream) and IC2 (downstream), respectively. From May 1994 to the end of 2015, UCSF has treated 1838 proton ocular patients at the Davis ETF. During this period, no treatments were missed due to any cyclotron or control system failures. The overall performance,

关键词： Proton Beam Therapy Beam Delivery Control System Ocular Tumors

关于^(12)C+^(16)O反应的三体出射道的研究

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高能物理与核物理 1991年第8期15卷 748-753页

作者：孔祥儆李盘林 j.j.kolata j.Vega k.A.kryger F.W.Prosser P.A.Deyoung 中国科学院上海原子核研究所 Department of Physics University of Notre DameNotre Dame In46556 U.S.A. University of kansas Lawrence KS66045 U.S.A. Hope College Holland MI49423 U.S.A.

我们用两个带电粒子符合方法研究了能量为56MeV的^(16)O轰击^(12)C的三体反应出射道,分别得到了两个不同的三体出射道:α_1+α_2+^(20)Ne和p+α+^(23)Na的反应Q值谱,两道之间的比为8:1,同时得到了α_1+α_2两维符合事件的投影谱,结果显... 详细信息

我们用两个带电粒子符合方法研究了能量为56MeV的^(16)O轰击^(12)C的三体反应出射道,分别得到了两个不同的三体出射道:α_1+α_2+^(20)Ne和p+α+^(23)Na的反应Q值谱,两道之间的比为8:1,同时得到了α_1+α_2两维符合事件的投影谱,结果显示α+^(24)Mg是α_1+α_2+^(20)Ne出射道的主要中间过程。理论分析告诉我们,两体的两步连续衰变与剥裂机制的统计计算相加,满意地和实验能谱符合,但是,从运动学计算来说,~8Be_(1st)+^(20)Ne~*,然后~8Be_(1st)→α_1+α_2的连续衰变机制也是不能完全排除的。

关键词： ^12C ^16O 三体反应出射道

Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(S)NN=200 GeV

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Chinese Physics C 2021年第4期45卷 198-241页

作者： H.Agakishiev M.M.Aggarwal Z.Ahammed A.V.Alakhverdyants I.Alekseev j.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.S.Averichev j.Balewski D.R.Beavis N.k.Behera R.Bellwied M.j.Betancourt R.R.Betts A.Bhasin A.k.Bhat H.Bichsel j.Bieleik j.Bielcikova B.Biritz L.C.Bland W.Borowski j.Bouchet E.Braidot A.V.Brandin A.Bridgeman S.G.Brovko E.Bruna S.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai H.Caines M.Calderon de la Barca Sanchez D.Cebra R.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka S.Chattopadhyay H.F.Chen j.H.Chen j.Y.Chen L.Chen j.Cheng M.Cherney A.Chikanian k.E.Choi W.Christie P.Chung M.j.M.Codrington R.Corliss j.G.Cramer H.j.Crawford S.Dash A.Davila Leyva L.C.De Silvat R.R.Debbe T.G.Dedovich A.A.Derevschikov R.Derradi de Souza L.Didenko P.Djawotho S.M.Dogra X.Dong j.L.Drachenberg j.E.Draper j.C.Dunlop L.G Efimov M.Elnim j.Engelage G Eppley M.Estienne L.Eun O.Evdokimov R.Fatemi j.Fedorisin A.Feng R.G.Fersch P.Filip E.Finch V.Fine Y.Fisyak C.A.Gagliardi D.R.Gangadharan A.Geromitsos F.Geurts P.Ghosh Y.N.Gorbunov A.Gordon O.Grebenyuk D.Grosnick S.M.Guertin A.Gupta W.Guryn B.Haag O.Hajkova A.Hamed L-X.Han j.W.Harris j.P.Hays-Wehle M.Heinz S.Heppelmann A.Hirsch E.Hjort G.W.Hoffmann D.j.Hofiman B.Huang H.Z.Huang T.j.Humanic L.Huo G.Igo P.jacobs W.W.jacobs C.jena F.jin j.joseph E.G.judd S.kabana k.kang j.kapitan k.kauder H.ke D.keane A.kechechyan D.kettler D.P.kikola j.kiryluk A.kisiel V.kizka A.G.knospe D.D.koetke T.kollegger j.konzer I.koralt L.koroleva W.korsch L.kotchenda V.kouchpil P.kravtsov k.krueger M.krus L.kumar P.kurnadi M.A.C.Lamont j.M.Landgraf S.LaPointe j.Lauret A.Lebedev R.Lednicky j.H.Lee W.Leight M.j.LeVine C.Lil L.Li N.Li W.Li X.Li X.Li Y.Li Z.M.Li M.A.Lisa F.Liu H.Liu j.Liu T.Ljubicic W.j.Llope R.S.Longacre W.A.Love Y.Lu E.V.Lukashov X.Luo G.L.Ma Y.G.Mai D.P.Mahapatra R.Majka O.I.Mall L.k.Mangotra R.Manweiler S.Margetis C.Markert H.Masui H.S.Matis Yu.A.Matulenko D.MeDonald T.S.McShane A.Meschanin R.Milner N.G.Minaev S.Mioduszewski A.Mischke M.k.Mitrovski B.Mohanty M.M.Mondal B.Morozov D.A.Morozov M.G.Munhoz M Argonne National Laboratory Argonnellinois 60439USA Brookhaven National Laboratory UptonNew York 11973USA University of Califomia BerkeleyCaliformnia 94720USA University of California DavisCalifornia 95616USA University of Califormnia Los AngelesCalifomia 90095USA Universidade Estadual de Campinas Sao PauloBrazil University of Illinois at Chicago ChicagoIlinois 60607USA Creighton University OmahaNebraska 68178USA Czech Technical University in Prague FNSPEPrague11519Czech Republic Nuclear Physics Institute AS CR 25068 Rez/PragueCzech Republic University of Frankfurt FrankfurtGermany Institute of Physics Bhubaneswar 751005India Indian Institute of Technology MumbaiIndia Indiana University BloomingtonIndiana 47408USA Alikhanov Instiute for Theoretical and Experimental Physics MoscowRussia University of jammu Jammu 180001India joint Institute for Nuclear Research Dubna141980Russia kent State University KentOhio 44242USA University of kentucky LexingtonKentucky40506-0055USA Institute of Modern Physics LanzhouChina lawrence Berkeley National Laboratory BerkeleyCalifornia 94720USA Massachusetts Institute of Technology CambridgeMA 02139-4307USA Mx-Planck-Institut fir Physik MunichGermany Michigan State University East LansingMichigan 48824USA Moscow Engineering Physics Institute Moscow Russia NIkHEF and Utrecht University AmsterdamThe Netherlands Ohio State University ColumbusOhio 43210USA Old Dominion University NorfolkVA23529USA Panjab University Chandigarh 160014India PennsyIvania State University University ParkPennsylvania 16802USA Institute of High Energy Physics ProtvinoRussia Purdue University West LafayetteIndiana 47907USA Pusan National University PusanRepublic of Korea University of Rajasthan Jaipur 302004India Rice University HoustonTexas 77251USA Universidade de Sao Paulo Sao PauloBrazil University of Science&Technology of China Hefei 230026.China Shandong University JinanShandong 250100China Shanghai Institute of Applied Physics Shanghai 201800Chi

Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium,*** measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au *** modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching *** paper reports STAR measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(S)NN=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle *** subtractions of the combinatorial background and anisotropic flow,assuming Zero Yield At Minimum(ZYAM),are *** correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow *** away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger *** near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately *** correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from *** is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak *** dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open *** with aФ_(s)-dependent elliptic flow,the away-side correlation structure

关键词： relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane

EFFECT OF COLD-ROLLING ON THE MAGNETTIC TTRANSITIONS IN Au_(83)Fe_(17)

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Chinese Physics Letters 1988年第3期5卷 129-132页

作者： CHEN Duxing j.Nogues k.V.Rao C.E.Violet *** Department of Solid State Physics Royal Institute of TechnologyStockholmSweden Central Iron and Steel Research Institute Beijing lawrence Livermore Labs. LivermoreCA94550

The temperature dependences of the dynamic-elastic and viscous susceptibilities have been measured for Au83Fe17, after cold-rolling. It is found that cold-rolling reduces the Curie temperature and raises the spin-freezing temperature remarkably. These results can be explained on the basis of the precipitation medal proposed by Borg and Violet.

关键词： freezing viscous remarkably

^(146)Ce核的八级形变带和准γ带(英文)

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高能物理与核物理 2006年第8期30卷 740-744页

作者：陈永静朱胜江 j. H. Hamilton A. V. Ramayya j. k. Hwang Y. X. Luo j. O. Rasmussen 车兴来丁怀博李明亮清华大学物理系北京100084 Department of Physics Vanderbilt University Nashville Tennessee 37235 USA lawrence Berkeley National Laboratory Berkeley California 94720 USA

通过测量252Cf自发裂变所产生的瞬发γ射线,对146Ce核的高自旋结构进行了重新研究,结果更新了以前报道的能级纲图,把八级形变集体带扩展到更高的自旋,并且重新构建了可能的准γ带结构．此外,用反射不对称壳模型(RASM)对146Ce核的八级形... 详细信息

通过测量252Cf自发裂变所产生的瞬发γ射线,对146Ce核的高自旋结构进行了重新研究,结果更新了以前报道的能级纲图,把八级形变集体带扩展到更高的自旋,并且重新构建了可能的准γ带结构．此外,用反射不对称壳模型(RASM)对146Ce核的八级形变带进行了计算,低自旋处的计算结果与实验数据符合得很好．

关键词：高自旋态八级形变带准γ带壳模型

Methods of Approximation in hpk Framework for ODEs in Time Resulting from Decoupling of Space and Time in IVPs

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American journal of Computational Mathematics 2011年第2期1卷 83-103页

作者： k.S. Surana L. Euler j.N. Reddy A. Romkes University of kansas Mechanical Engineering Department Lawrence KS 66045

The present study considers mathematical classification of the time differential operators and then applies methods of approximation in time such as Galerkin method (GM ), Galerkin method with weak form (GM / WF ), Petrov-Galerkin method ( PGM), weighted residual method (WRY ), and least squares method or process ( LSM or LSP ) to construct finite element approximations in time. A correspondence is established between these integral forms and the elements of the calculus of variations: 1) to determine which methods of approximation yield unconditionally stable (variationally consistent integral forms, VC ) computational processes for which types of operators and, 2) to establish which integral forms do not yield unconditionally stable computations (variationally inconsistent integral forms, VIC ). It is shown that variationally consistent time integral forms in hpk framework yield computational processes for ODEs in time that are unconditionally stable, provide a mechanism of higher order global differentiability approximations as well as higher degree local approximations in time, provide control over approximation error when used as a time marching process and can indeed yield time accurate solutions of the evolution. Numerical studies are presented using standard model problems from the literature and the results are compared with Wilson’s θ method as well as Newmark method to demonstrate highly meritorious features of the proposed methodology.

关键词： Finite Element Approximations Numerical Studies Time Approximation Variationally Consis- tent Integral Forms