Abbas Ibrahim A （Ibrahim A Abbas） and Othman Mohamed I A （Mohamed I A Othman）, Generalized thermoelsticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli, 20...Abbas Ibrahim A （Ibrahim A Abbas） and Othman Mohamed I A （Mohamed I A Othman）, Generalized thermoelsticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli, 2012 21（1） 014601 Abbas Ibrahim A （Ibrahim A Abbas）, Kumar Rajneesh （Rajneesh Kumar） and Chawla Vijay （Vijay Chawla）, Response of thermal source in a transversely isotropic thermoelastic half-space with mass diffusion by using a finite element method, 2012 21（8） 084601展开更多
An amplitude analysis of the Dsi(2460)+→D,π+π-transition is performed simultaneously in BO→D'D,π+π-,B+-D'D,π+π,and BO-D-D,π+π-decays.The study is based on a data sample of proton-proton collisions re...An amplitude analysis of the Dsi(2460)+→D,π+π-transition is performed simultaneously in BO→D'D,π+π-,B+-D'D,π+π,and BO-D-D,π+π-decays.The study is based on a data sample of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of Vs=7,8,and 13Tev,corresponding to a total integrated luminosity of 9fb-1.A clear double-peak structure is observed in the m(π+π~)spectrum of the Ds1(2460)+→D,π+π-decay.The data can be described either with a model including fo(500),o(980),and f2(1270)resonances,in which the contributions of fo(980)and f2(1270)are unexpectedly large,or with a model including fo(500),a doubly charged open-charm tetraquark state Tt and its isospin partner Tes.If the former is considered implausible,the Tes states are observed with high significance,and the data are consistent with isospin symmetry.When imposing isospin constraints between the two Tes states,their mass and width are determined to be(2327±13±13)Mev and(96±16+70)Mev,respectively,where the first uncertainty is statistical 23 and the second is systematic.The mass is slightly below the DK threshold,and a spin-parity of o+is favoured with high significance.展开更多
We examine the effects of an unparticle U as a possible source of missing energy in the p-wave decays of a B meson. The dependence of the differential branching ratio on the K0^＊ （K1） - meson＇s energy is discussed...We examine the effects of an unparticle U as a possible source of missing energy in the p-wave decays of a B meson. The dependence of the differential branching ratio on the K0^＊ （K1） - meson＇s energy is discussed in the presence of scalar and vector unparticle operators and significant deviation from the standard model value is found after addition of these operators. Finally, we have shown the dependence of the branching ratio for the above-mentioned decays on the parameters of unparticle stuff like effective couplings, cutoff scale Au and the scale dimensions du.展开更多
We investigate the two loop electroweak corrections to B meson rare decays B¯→Xsγand B0s→μ+μ−in the minimal supersymmetry standard model(MSSM)extension with two triplets and one singlet(TNMSSM).The new parti...We investigate the two loop electroweak corrections to B meson rare decays B¯→Xsγand B0s→μ+μ−in the minimal supersymmetry standard model(MSSM)extension with two triplets and one singlet(TNMSSM).The new particle contents and interactions in the TNMSSM can affect the theoretical predictions of the branching ratios Br(B¯→Xsγ)and Br(B0s→μ+μ−),and the corrections from two loop diagrams to the process B¯→Xsγcan reach around 4%.Considering the latest experimental measurements,the numerical results of Br(B¯→Xsγ)and Br(B0s→μ+μ−)in the TNMSSM are presented and analyzed.The findings indicate that the results in the TNMSSM can fit the updated experimental data well,and the new parameters Tλ,κ,λ,clearly affect the theoretical predictions of Br(B¯→Xsγ)and Br(B0s→μ+μ−).展开更多
A first search for the Ξ_(bc)^(+)J/ψΞ_(c)^(+) decay is performed by the LHCb experiment with a data sample of proton-proton collisions, corresponding to an integrated luminosity of 9 fb−1 recorded at centre-of-mass...A first search for the Ξ_(bc)^(+)J/ψΞ_(c)^(+) decay is performed by the LHCb experiment with a data sample of proton-proton collisions, corresponding to an integrated luminosity of 9 fb−1 recorded at centre-of-mass energies of 7, 8, and 13 TeV. Two peaking structures are seen with a local (global) significance of 4.3(2.8) and 4.1(2.4) standard deviations at masses of 6571 and 6694 MeV/c2, respectively. Upper limits are set on the Ξ+bc baryon production cross-section times the branching fraction relative to that of the B+c→J/ψD+s decay at centre-of-mass energies of 8 and 13 TeV, in the Ξ+bc and in the B+c rapidity and transverse-momentum ranges from 2.0 to 4.5 and 0 to 20GeV/c, respectively. Upper limits are presented as a function of the Ξ+bc mass and lifetime.展开更多
The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)baryon are performed using pp collision data collected via the LHCb experiment from 2016 to 2018 at a centre-of-mass energy of 13 T...The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)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 Λ^(+)_(c)π^(-)and E^(+)_(c)π^(-).No significant excess is fbund for invariant masses between 6700 and 7300 MeV/c^(2),in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ω^(0)_(bc)and E^(0)_(bc)production cross-section times the branching fraction to Λ^(+)_(c)π^(-)(E^(+)_(c)π^(-))relative to that of the Λ^(0)_(b)(E^(0)_(b))baryon,for different lifetime hypotheses,at 95%confidence level.The upper limits range from 0.5 x 10^(-4)to 2.5 x 10^(-4)for theΩ^(0)_(bc)→Λ^(+)_(c)π^(-)(E^(0)_(bc)→Λ^(+)_(c)π^(-))decay,and from 1.4x 10^(-3)to 6.9 x 10^(-3)for theΩ^(0)_(bc)→E^(+)_(c)π^(-)(E^(0)_(bc)→E^(+)_(c)π^(-))decay,depending on the considered mass and lifetime of theΩ^(0)_(bc)(E^(0)_(bc))baryon.展开更多
A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No signific...A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No significant signal of the decay is observed and an upper limitof 1.1x 10^(-7)at 90%confidence level is set on the branching fraction.展开更多
In this paper,we summarize the existing methods of solving the evolution equation of the leading-twist B-meson LCDA.Then,in the Mellin space,we derive a factorization formula with next-to-leading-logarithmic(NLL)resum...In this paper,we summarize the existing methods of solving the evolution equation of the leading-twist B-meson LCDA.Then,in the Mellin space,we derive a factorization formula with next-to-leading-logarithmic(NLL)resummation for the form factors FA,V in the B→γℓνdecay at leading power inΛ/mb.Furthermore,we investigate the power suppressed local contributions,factorizable non-local contributions(which are suppressed by 1/Eγand 1/mb),and soft contributions to the form factors.In the numerical analysis,which employs the two-loop-level hard function and the jet function,we find that both the resummation effect and the power corrections can sizably decrease the form factors.Finally,the integrated branching ratios are also calculated for comparison with future experimental data.展开更多
Within the framework of the perturbative QCD approach,we calculate the time-like B（c ）Bc（Bc＊）form factors F（Q^2）and A2（Q^2）.We include relativistic corrections and QCD corrections,either of which can give abo...Within the framework of the perturbative QCD approach,we calculate the time-like B（c ）Bc（Bc＊）form factors F（Q^2）and A2（Q^2）.We include relativistic corrections and QCD corrections,either of which can give about20%correction to the leading-order contribution,but there are cancellation effects between them.We calculate the cross sections of the e^＋e^-→Bc-Bc＋（Bc＊＋）processes.The cross sections are enhanced at the Z pole to beσ^（P P）（Q=m Z）～1.3×10^-5pb andσ^（P V）（Q=m Z）～2.5×10^-5pb,which are still too small to be detected by proposed e~＋e^-colliders such as the Circular Electron Positron Collider.展开更多
文摘Abbas Ibrahim A （Ibrahim A Abbas） and Othman Mohamed I A （Mohamed I A Othman）, Generalized thermoelsticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli, 2012 21（1） 014601 Abbas Ibrahim A （Ibrahim A Abbas）, Kumar Rajneesh （Rajneesh Kumar） and Chawla Vijay （Vijay Chawla）, Response of thermal source in a transversely isotropic thermoelastic half-space with mass diffusion by using a finite element method, 2012 21（8） 084601
基金support from CERN and from the national agencies:CAPES,CNPq,FAPERJ and FINEP(Brazil)MOST and NSFC(China)+12 种基金CNRS/IN2P3(France)BMBF,DFG and MPG(Germany)INFN(Italy)NWO(Netherlands)MNi SW and NCN(Poland)MCID/IFA(Romania)MICIU and AEI(Spain)SNSF and SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)DOE NP and NSF(USA)Key Research Program of Frontier Sciences of CAS,CAS PIFI,CAS CCEPP,Fundamental Research Funds for the Central UniversitiesSci.&Tech.Program of Guangzhou(China)。
文摘An amplitude analysis of the Dsi(2460)+→D,π+π-transition is performed simultaneously in BO→D'D,π+π-,B+-D'D,π+π,and BO-D-D,π+π-decays.The study is based on a data sample of proton-proton collisions recorded with the LHCb detector at centre-of-mass energies of Vs=7,8,and 13Tev,corresponding to a total integrated luminosity of 9fb-1.A clear double-peak structure is observed in the m(π+π~)spectrum of the Ds1(2460)+→D,π+π-decay.The data can be described either with a model including fo(500),o(980),and f2(1270)resonances,in which the contributions of fo(980)and f2(1270)are unexpectedly large,or with a model including fo(500),a doubly charged open-charm tetraquark state Tt and its isospin partner Tes.If the former is considered implausible,the Tes states are observed with high significance,and the data are consistent with isospin symmetry.When imposing isospin constraints between the two Tes states,their mass and width are determined to be(2327±13±13)Mev and(96±16+70)Mev,respectively,where the first uncertainty is statistical 23 and the second is systematic.The mass is slightly below the DK threshold,and a spin-parity of o+is favoured with high significance.
基金National Science Foundation of China (10735080 and 10625525)China Postdoctoral Science Foundation
文摘We examine the effects of an unparticle U as a possible source of missing energy in the p-wave decays of a B meson. The dependence of the differential branching ratio on the K0^＊ （K1） - meson＇s energy is discussed in the presence of scalar and vector unparticle operators and significant deviation from the standard model value is found after addition of these operators. Finally, we have shown the dependence of the branching ratio for the above-mentioned decays on the parameters of unparticle stuff like effective couplings, cutoff scale Au and the scale dimensions du.
基金Supported by the National Natural Science Foundation of China(12075074,12235008,11535002,11705045)the Natural Science Foundation for Distinguished Young Scholars of Hebei Province,China(A2022201017)+1 种基金the Natural Science Foundation of Guangxi Autonomous Region(2022GXNSFDA035068)the Youth Top-NotchTalent Support Programof theHebei Province,China。
文摘We investigate the two loop electroweak corrections to B meson rare decays B¯→Xsγand B0s→μ+μ−in the minimal supersymmetry standard model(MSSM)extension with two triplets and one singlet(TNMSSM).The new particle contents and interactions in the TNMSSM can affect the theoretical predictions of the branching ratios Br(B¯→Xsγ)and Br(B0s→μ+μ−),and the corrections from two loop diagrams to the process B¯→Xsγcan reach around 4%.Considering the latest experimental measurements,the numerical results of Br(B¯→Xsγ)and Br(B0s→μ+μ−)in the TNMSSM are presented and analyzed.The findings indicate that the results in the TNMSSM can fit the updated experimental data well,and the new parameters Tλ,κ,λ,clearly affect the theoretical predictions of Br(B¯→Xsγ)and Br(B0s→μ+μ−).
基金The project support from CERN and from the national agencies:CAPES,CNPq,FAPERJ and FINEP(Brazil)MOST and NSFC(China)+18 种基金CNRS/IN2P3(France)BMBF,DFG and MPG(Germany)INFN(Italy)NWO(Netherlands)MNiSW and NCN(Poland)MEN/IFA(Romania)MICINN(Spain)SNSF and SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)DOE NP and NSF(USA).We acknowledge the computing resources that are provided by CERN,IN2P3(France),KIT and DESY(Germany),INFN(Italy),SURF(Netherlands),PIC(Spain),GridPP(United Kingdom),CSCS(Switzerland),IFIN-HH(Romania),CBPF(Brazil),Polish WLCG(Poland)and NERSC(USA).Individual groups or members have received support from ARC and ARDC(Australia)Minciencias(Colombia)AvH Foundation(Germany)EPLANET,Marie Sklodowska-Curie Actions and ERC(European Union)A*MIDEX,ANR,IPhU and Labex P2IO,and Région Auvergne-RhôneAlpes(France)Key Research Program of Frontier Sciences of CAS,CAS PIFI,CAS CCEPP,Fundamental Research Funds for the Central Universities,and Sci.&Tech.Program of Guangzhou(China)GVA,XuntaGal,GENCAT and Prog.Atracción Talento,CM(Spain)SRC(Sweden)the Leverhulme Trust,the Royal Society and UKRI(United Kingdom).
文摘A first search for the Ξ_(bc)^(+)J/ψΞ_(c)^(+) decay is performed by the LHCb experiment with a data sample of proton-proton collisions, corresponding to an integrated luminosity of 9 fb−1 recorded at centre-of-mass energies of 7, 8, and 13 TeV. Two peaking structures are seen with a local (global) significance of 4.3(2.8) and 4.1(2.4) standard deviations at masses of 6571 and 6694 MeV/c2, respectively. Upper limits are set on the Ξ+bc baryon production cross-section times the branching fraction relative to that of the B+c→J/ψD+s decay at centre-of-mass energies of 8 and 13 TeV, in the Ξ+bc and in the B+c rapidity and transverse-momentum ranges from 2.0 to 4.5 and 0 to 20GeV/c, respectively. Upper limits are presented as a function of the Ξ+bc mass and lifetime.
基金CAPES,CNPq,FAPERJ and FINEP(Brazil)MOST and NSFC(China)+18 种基金CNRS/IN2P3(France)BMBF,DFG,MPG(Germany)INFN(Italy)NWO(Netherlands)MNiSW,NCN(Poland)MEN/IFA(Romania)MSHE(Russia)MICINN(Spain)SNSF,SER(Switzerland)NASU(Ukraine)STFC(United Kingdom)DOE NP,NSF(USA).We acknowledge the computing resources that are provided by CERN,IN2P3(France),KIT and DESY(Germany),INFN(Italy),SURF(Netherlands),PIC(Spain),GridPP(United Kingdom),RRCKI and Yandex LLC(Russia),CSCS(Switzerland),IFIN-HH(Romania),CBPF(Brazil),PL-GRID(Poland)and NERSC(USA)AvH Foundation(Germany)EPLANET,Marie Sklodowska-Curie Actions and ERC(European Union)A*MIDEX,ANR,Labex P2IO and OCEVU,Region Auvergne-Rhdne-Alpes(France)Key Research Program of Frontier Sciences of CAS,CAS PIFI,CAS CCEPP,Fundamental Research Funds for the Central Universities,and Sci.Tech.Program of Guangzhou(China)RFBR,RSF and Yandex LLC(Russia)GVA,XuntaGal,GENCAT(Spain)the Leverhulme Trust,the Royal Society and UKRI(United Kingdom)。
文摘The first search for the doubly heavyΩ^(0)_(bc)baryon and a search for the E^(0)_(bc)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 Λ^(+)_(c)π^(-)and E^(+)_(c)π^(-).No significant excess is fbund for invariant masses between 6700 and 7300 MeV/c^(2),in a rapidity range from 2.0 to 4.5 and a transverse momentum range from 2 to 20 MeV/c.Upper limits are set on the ratio of the Ω^(0)_(bc)and E^(0)_(bc)production cross-section times the branching fraction to Λ^(+)_(c)π^(-)(E^(+)_(c)π^(-))relative to that of the Λ^(0)_(b)(E^(0)_(b))baryon,for different lifetime hypotheses,at 95%confidence level.The upper limits range from 0.5 x 10^(-4)to 2.5 x 10^(-4)for theΩ^(0)_(bc)→Λ^(+)_(c)π^(-)(E^(0)_(bc)→Λ^(+)_(c)π^(-))decay,and from 1.4x 10^(-3)to 6.9 x 10^(-3)for theΩ^(0)_(bc)→E^(+)_(c)π^(-)(E^(0)_(bc)→E^(+)_(c)π^(-))decay,depending on the considered mass and lifetime of theΩ^(0)_(bc)(E^(0)_(bc))baryon.
基金support from AvH Foundation(Germany)EPLANET,Marie Sk lodowska-Curie Actions and ERC(European Union)+11 种基金A*MIDEXANRLabex P2IOOCEVURégion Auvergne-Rh?ne-Alpes(France)Key Research Program of Frontier Sciences of CASCAS PIFIThousand Talents ProgramSci.&Tech.Program of Guangzhou(China)RFBR,RSF and Yandex LLC(Russia)GVA,Xunta Gal and GENCAT(Spain)the Royal Society and the Leverhulme Trust(United Kingdom)。
文摘A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No significant signal of the decay is observed and an upper limitof 1.1x 10^(-7)at 90%confidence level is set on the branching fraction.
基金Y.B.W is Supported in part by the National Natural Science Foundation of China(NSFC)(11675082,11735010)。
文摘In this paper,we summarize the existing methods of solving the evolution equation of the leading-twist B-meson LCDA.Then,in the Mellin space,we derive a factorization formula with next-to-leading-logarithmic(NLL)resummation for the form factors FA,V in the B→γℓνdecay at leading power inΛ/mb.Furthermore,we investigate the power suppressed local contributions,factorizable non-local contributions(which are suppressed by 1/Eγand 1/mb),and soft contributions to the form factors.In the numerical analysis,which employs the two-loop-level hard function and the jet function,we find that both the resummation effect and the power corrections can sizably decrease the form factors.Finally,the integrated branching ratios are also calculated for comparison with future experimental data.
基金Supported by Natural Science Foundation of Shandong Province,China(ZR2015AQ006)National Natural Science Foundation of China(11521505,11621131001,11447009,11505098,11765012)R.H.Li is partly supported by the plan of Young Creative Talents under the Talent of the Prairie project of the Inner Mongolia
文摘Within the framework of the perturbative QCD approach,we calculate the time-like B（c ）Bc（Bc＊）form factors F（Q^2）and A2（Q^2）.We include relativistic corrections and QCD corrections,either of which can give about20%correction to the leading-order contribution,but there are cancellation effects between them.We calculate the cross sections of the e^＋e^-→Bc-Bc＋（Bc＊＋）processes.The cross sections are enhanced at the Z pole to beσ^（P P）（Q=m Z）～1.3×10^-5pb andσ^（P V）（Q=m Z）～2.5×10^-5pb,which are still too small to be detected by proposed e~＋e^-colliders such as the Circular Electron Positron Collider.
