检索结果-南通市图书馆

Chinese Physics C 2009年第9期33卷 764-768页

作者：张进娟许昌任中洲 Department of Physics Nanjing University Department of Physics Nanjing University Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou

We present a systematic calculation on the α-decay branching ratios to excited-states of an even-even α-decay chain ^242Cm → ^238Pu → ^234U → ^230Th → ^226Rn by the improved barrier penetration approach. The changes of the parities between the parent nuclei and the daughter nuclei are properly taken into account. The theoretical values are compared with the available experimental data and the deviation between them is within a factor of 5 in most cases.

关键词： alpha-decay branching ratios high-lying excited states parity

Radiative leptonic decay of heavy quarkonia

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第10期48卷 114-124页

作者： Junle Pei Xinchou Lou Yaquan Fang Jinfei Wu Manqi Ruan Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China University of Texas at Dallas RichardsonTXUSA China Center of Advanced Science and Technology Beijing 100190China

In this study,the properties of heavy quarkonia X are examined by treating them as bound states of Q and Q at the leading-order level within the non-relativistic quantum chromodynamics(NROCD)framework,where Q represents either a charm or bottom *** branching ratios for the radiative leptonic decays X→γl^(+)l^(-)are revisited,and the angular and energy/momentum distributions of the final state particles are analyzed in the restframe of ***,we apply Lorentz transformations from the rest frame of X to the center-of-mass frame of l^(+)l^(-)to establish the connection between the widths Г_(x→γl^(+)l^(-))and Г_(x→l^(+)l^(-)).The comparison of the connection tothose documented in literature(divided by 2π)for various X states,such as J/Ψ,Ψ(2S),Υ(1S),and Υ(2S),shows relative differences typically around or below 10%,comparable to the next-to-leading order corrections of O(α)and 0(ν^(4)).However,we observe a significant disparity in the ratio betweenГ_(Ψ(2S)→γτ^(+)τ^(-))andГ_(Ψ(2S)→τ^(+)τ^(-)),with our prediction being four times larger than those in *** outcomes derived from this study have practical *** in describing the quantum electrodynamics radiative processes and contribute to the investigation of QCD processes associated with the decays of heavy quarkonia and searches for new physies.

关键词： heavy quarkonia radiative leptonic decays branching ratios

Light axion-like particles and the pseudoscalar mesonic decays M→M′vv

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第9期76卷 37-41页

作者： Guo-Qiang Dai Chong-Xing Yue Yang-Yang Bu Yi-Hang Wang Department of physics Liaoning Normal UniversityDalian 116029China Center for Theoretical and Experimental High Energy Physics Liaoning Normal UniversityDalian 116029China

The axion-like particle(ALP)is one kind of the best-motivated new *** consider its production from the pseudoscalar mesonic decays M→M′a,with M being a pseudoscalar meson B or *** upper limits on the flavor-conserving ALP–quark coupling parameter guare obtained by assuming the ALP to be an invisible *** find that the most severe constraint on gucomes from the decay K^(+)→π^(+)vv for 0.05 Ge V≤M_(a)≤0.35 Ge V,while the decays B^(+,0)→K^(+,0)vvand B^(+,0)→π^(+,0)υvcan also generate significant constraints.

关键词： axion-like particle pseudoscalar mesons branching ratios

Investigation of decay modes of superheavy nuclei

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2021年第11期32卷 146-162页

作者： H.C.Manjunatha N.Sowmya P.S.Damodara Gupta K.N.Sridhar A.M.Nagaraja L.Seenappa S.Alfred Cecil Raj Department of Physics Government College for WomenKolarKarnataka 563101India Department of Physics Government First Grade CollegeKolarKarnataka 563101India Department of Physics St.Joseph’s CollegeAffiliated to Bharathidasan UniversityTiruchirappalliTamil NaduIndia

A detailed investigation of different decay modes,namely alpha decay,beta decay,cluster decay including heavy particle emission(Z_(c)>28),and spontaneous fission,was carried out,leading to the identification of new cluster and beta-plus emitters in superheavy nucle with 104≤Z≤*** the first time,we identified around20 beta-plus emitters in superheavy ***-particle radioactivity was observed in superheavy elements of atomic number in the range 116≤Z≤126.^(292-293)Og were identified as ^(86)Kr emitters,and ^(298)122 and ^(300)122 were identified as ^(94)Zr emitters,whereas heavy-particle radioactivity from ^(91)Y was also observed in ^(299)***,the nuclei ^(300)124 and ^(306)126 exhibit ^(96)Mo *** reported regions of beta-plus and heavyparticle radioactivity for superheavy nuclei are stronger than those for alpha *** identified decay modes for superheavy nuclei are presented in a *** study is intended to serve as a reference for identifying possible decay modes in the superheavy region.

关键词： Alpha decay Beta decay Heavy-particle radioactivity branching ratios

Study of semileptonic decays B_s →D_(s1)(2536)l and B_s →D_(s2)(2573)l in the CQM model

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2008年第8期32卷 603-607页

作者：赵树民张印杰阎玉立刘立全武利平 College of Physics Science and Technology Hebei University

Based on the assumption that Ds1（2536） and Ds2（2573） belong to T doublet （1^＋,2^＋）, we calculate the semileptonic decays of Bs to Ds1（2536） and Ds2（2573） in terms of the Constituent Quark Meson （CQM） model. For Bs → Ds1 （2536）＋ lv^- and B→ → Ds2 （2573）＋lv^-, the order of magnitude of the obtained branching ratios is 10^-3. Our numerical results of the semileptonic decays of Bs to Ds1（2536） and Ds2（2573） are large, which implies that two semileptonic decays should be seen in future experiments.

关键词： semileptonic decay CQM model branching ratios

Top rare decays t→cV in mirror twin Higgs models

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第1期45卷 82-88页

作者： Su-Ya Bie Guo-Li Liu Wenyu Wang School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Physics Beijing University of TechnologyBeijing 100124China

The decay t→cV(V=γ,Z,g)processes in mirror twin Higgs models with colorless top partners are studied in this *** report that the branchi ng ratios of these decays can strongly affect the standard model expectations in some parameter spaces and may be detectable according to the current precision electroweak ***,constraints on the model parameters may be obtained from the branching fraction of the decay processes,which may serve as a robust detection tool for this new physics model.

关键词： mirror twin Higgs models t→cV branching ratios

B→K0^＊（1430）K Decays in Perturbative QCD Approach

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2010年第3期53卷 540-544页

作者：刘新肖振军 Department of Physics and Institute of Theoretical Physics Nanjing Normal University

In this article, we calculate the branching ratios of B→K0^＊（1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.

关键词： B meson decays branching ratios the perturbative QCD approach

Pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)in the PQCD approac

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2021年第4期73卷 82-91页

作者： Yutong Chen Zewen Jiang Xin Liu Department of Physics Jiangsu Normal UniversityXuzhou 221116China

We study the CP-averaged branching fractions and the CP-violating asymmetries in the pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0),where a_(0)[K^(∗)_(0)]denotes the scalar a_(0)(980)and a_(0)(1450)[K^(∗)_(0)(800)(orκ)and K^(∗)_(0)(1430)],with the perturbative QCD factorization approach under the assumption of two-quark structure for the a_(0)and K^(∗)_(0)*** numerical results show that the branching ratios of the B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)decays are in the order of 10^(−6),while the decay rates of the B^(s)_(0)→a^(+)_(0)a^(−)_(0)modes are in the order of 10−*** light of the measured modes with the same quark components in the pseudoscalar sector,namely,B^(0)_(d)→K^(+)k_(-)and B^(0)_(s)→π^(+)π_(−),the predictions for the considered decay modes in this work are expected to be measured at the Large Hadron Collider beauty and/or Belle-Ⅱexperiments in the(near)***,it is of great interest to find that the twist-3 distribution amplitudesφ^(S)andφ^(T)with inclusion of the Gegenbauer polynomials for the scalar a_(0)(1450)and K^(∗)_(0)(1430)states in scenario 2 contribute slightly to the branching ratios while significantly to the CP violations in the B^(0)_(d)→K^(∗)_(0)(1430)+K^(∗)_(0)(1430)−and B^(0)_(s)→a_(0)(1450)+a_(0)(1450)−decays,which indicates that,compared to the asymptoticφ^(S)andφ^(T),these Gegenbauer polynomials could change the strong phases evidently in these pure annihilation decay *** predictions await for the future confirmation experimentally,which could further provide useful information to help explore the inner structure of the scalars and shed light on the annihilation decay mechanism.

关键词： B meson decays perturbative QCD factorization approach light scalar mesons branching ratios CP-violating asymmetries