In this paper,we undertake a detailed study of real scalar inflation using LATTICEEASY simulations to investigate preheating phenomena.Generally,the scalar inflation potential with non-minimal coupling can be approxim...In this paper,we undertake a detailed study of real scalar inflation using LATTICEEASY simulations to investigate preheating phenomena.Generally,the scalar inflation potential with non-minimal coupling can be approximated using a quartic potential.We observe that the evolutionary behavior of this potential remains unaffected by the coupling coefficient.Furthermore,the theoretical predictions for the scalar spectral index(n_(s))and tensor-toscalar power ratio(r)are independent of this coefficient.Consequently,the coefficients of this model are not constrained by Planck observations.Fortunately,the properties of preheating after inflation provide a viable approach to examining these coefficients.Through LATTICEEASY simulations,we trace the evolution of particle number density,scale factor,and energy density during the preheating process.Subsequently,we derive the parameters,such as the energy ratio(γ)and the e-folding number of preheating(N_(pre)),which facilitate further predictions of n s and r.We successfully validate real scalar inflation model using preheating in LATTICEEASY simulations based on the analytical relationship between preheating and inflation models.展开更多
We study the possibility of probing high scale phase transitions that are inaccessible by LIGO.Our study shows that the stochastic gravitational-wave radiation from cosmic strings that are formed after the first-order...We study the possibility of probing high scale phase transitions that are inaccessible by LIGO.Our study shows that the stochastic gravitational-wave radiation from cosmic strings that are formed after the first-order phase transition can be detected by space-based interferometers when the phase transition temperature is T_(n)~O(10^(8−11))GeV.展开更多
In this study,D→P(π,K) helicity form factors(HFFs) are investigated by applying the QCD light-cone sum rule(LCSR) approach.The calculation accuracy is up to the next-to-leading order(NLO) gluon radiation correction ...In this study,D→P(π,K) helicity form factors(HFFs) are investigated by applying the QCD light-cone sum rule(LCSR) approach.The calculation accuracy is up to the next-to-leading order(NLO) gluon radiation correction of twist-(2,3) distribution amplitude.The resultant HFFs at a large recoil point are Pt,0π(0)=0.688-0.024+0.020 and Pt,0K(O)=0.780-0.029+0.024,in which the contributions from the three particles of the leading order(LO) are so small that they can be safely neglected.The maximal contribution of the NLO gluon radiation correction for Pt,0r,K(0) is less than3%.After extrapolating the LCSR predictions for these HFFs to the whole q2-region,we obtain the decay widths for semileptonic decay processes D→Plvl,which are consistent with the BES-Ⅲ collaboration predictions within error limits.After considering the D+/D0-meson lifetime,we give the branching fractions of D→Plvl with l=e,μ;our predictions also agree with the BES-Ⅲ collaboration results within error limits,especially for the D→πlvl decay process.Finally,we present the forward-backward asymmetry AFBl(q2) and lepton convexity parameter CFl(q2),and further calculate the mean value of these two observations,<AFBl> and {CFl),which may provide a way to test those HFFs in future experiments.展开更多
The heavy quark effective field theory(HQEFT)provides an effective way to deal with heavy meson decays.In this paper,we adopt two different correlators to derive the light-cone sum rules(LCSR)for the B→πtransition f...The heavy quark effective field theory(HQEFT)provides an effective way to deal with heavy meson decays.In this paper,we adopt two different correlators to derive the light-cone sum rules(LCSR)for the B→πtransition form factors(TFFs)in the framework of HQEFT.We label the two LCSR results as LCSR-u and LCSR-R,which stand for the conventional correlator and the right-handed correlator.We observe that the correlation parameter|ρRU|for the branching ratio B(B→πlv_l)is^0.85,implying a consistency of LCSRs with the other correlators.Furthermore,we obtain|V_(ub)|_(LCSR-u)=(3.45_(-0.20)^(+0.28)±0.13_(exp))×10^(-3)and|V_(ub)|_(LCSR-R)=(3.38_(-0.16)^(+0.22)±0.12_(exp))×10^(-3).We also obtain R_π|_(LCSR-u)=0.68_(-0.09)^(+0.10)and R_π|_(LCSR-R)=0.65_(-0.11)^(+0.13),both of which agree with the lattice QCD predictions.Thus,HQEFT provides a useful framework for studying B meson decays.Moreover,by using the right-handed correlator,the twist-2 terms are dominant in TFF f^+(q^2),as their contribution is over^97%in the whole q^2 region,while the large twist-3 uncertainty of the conventional correlator is greatly suppressed.Hence,the LCSR-R predictions can be used to test the properties of the various models for the pion twist-2 distribution amplitudes.展开更多
基金Supported by the Natural Science Foundation of Chongqing,China(CSTB2022NSCQ-MSX0432)the Science and Technology Research Project of Chongqing Education Commission(KJQN202200621)+3 种基金the Chongqing Human Resources and Social Security Administration Program(D63012022005)Ruiyu Zhou was Supported by the Chongqing Natural Science Foundation(CSTB2022NSCQ-MSX0534)supported in part by the Fundamental Research Funds for the Central Universities(2021CDJQY-011)the National Natural Science Foundation of China(12147102)。
文摘In this paper,we undertake a detailed study of real scalar inflation using LATTICEEASY simulations to investigate preheating phenomena.Generally,the scalar inflation potential with non-minimal coupling can be approximated using a quartic potential.We observe that the evolutionary behavior of this potential remains unaffected by the coupling coefficient.Furthermore,the theoretical predictions for the scalar spectral index(n_(s))and tensor-toscalar power ratio(r)are independent of this coefficient.Consequently,the coefficients of this model are not constrained by Planck observations.Fortunately,the properties of preheating after inflation provide a viable approach to examining these coefficients.Through LATTICEEASY simulations,we trace the evolution of particle number density,scale factor,and energy density during the preheating process.Subsequently,we derive the parameters,such as the energy ratio(γ)and the e-folding number of preheating(N_(pre)),which facilitate further predictions of n s and r.We successfully validate real scalar inflation model using preheating in LATTICEEASY simulations based on the analytical relationship between preheating and inflation models.
基金supported in part by the National Key Research and Development Program of China(2021YFC2203004)in part by the National Natural Science Foundation of China(12075041,12047564)+1 种基金the Fundamental Research Funds for the Central Universities of China(2021CDJQY-011,2020CDJQY-Z003)Chongqing Natural Science Foundation(cstc2020jcyj-msxmX0814)。
文摘We study the possibility of probing high scale phase transitions that are inaccessible by LIGO.Our study shows that the stochastic gravitational-wave radiation from cosmic strings that are formed after the first-order phase transition can be detected by space-based interferometers when the phase transition temperature is T_(n)~O(10^(8−11))GeV.
基金Supported in part by the National Science Foundation of China(11765007)the National Natural Science Foundation of China(11947302)+1 种基金the Project of Guizhou Provincial Department of Science and Technology(KY[2017]1089,No.KY[2019]1171)the China Postdoctoral Science Foundation(2019TQ0329)。
文摘In this study,D→P(π,K) helicity form factors(HFFs) are investigated by applying the QCD light-cone sum rule(LCSR) approach.The calculation accuracy is up to the next-to-leading order(NLO) gluon radiation correction of twist-(2,3) distribution amplitude.The resultant HFFs at a large recoil point are Pt,0π(0)=0.688-0.024+0.020 and Pt,0K(O)=0.780-0.029+0.024,in which the contributions from the three particles of the leading order(LO) are so small that they can be safely neglected.The maximal contribution of the NLO gluon radiation correction for Pt,0r,K(0) is less than3%.After extrapolating the LCSR predictions for these HFFs to the whole q2-region,we obtain the decay widths for semileptonic decay processes D→Plvl,which are consistent with the BES-Ⅲ collaboration predictions within error limits.After considering the D+/D0-meson lifetime,we give the branching fractions of D→Plvl with l=e,μ;our predictions also agree with the BES-Ⅲ collaboration results within error limits,especially for the D→πlvl decay process.Finally,we present the forward-backward asymmetry AFBl(q2) and lepton convexity parameter CFl(q2),and further calculate the mean value of these two observations,<AFBl> and {CFl),which may provide a way to test those HFFs in future experiments.
基金Supported in part by the Natural Science Foundation of China(11625520,11765007,11375008,11647307,11847301)the Project of Guizhou Provincial Department of Science and Technology([2017]1089)the Key Project for Innovation Research Groups of Guizhou Provincial Department of Education(KY[2016]028)
文摘The heavy quark effective field theory(HQEFT)provides an effective way to deal with heavy meson decays.In this paper,we adopt two different correlators to derive the light-cone sum rules(LCSR)for the B→πtransition form factors(TFFs)in the framework of HQEFT.We label the two LCSR results as LCSR-u and LCSR-R,which stand for the conventional correlator and the right-handed correlator.We observe that the correlation parameter|ρRU|for the branching ratio B(B→πlv_l)is^0.85,implying a consistency of LCSRs with the other correlators.Furthermore,we obtain|V_(ub)|_(LCSR-u)=(3.45_(-0.20)^(+0.28)±0.13_(exp))×10^(-3)and|V_(ub)|_(LCSR-R)=(3.38_(-0.16)^(+0.22)±0.12_(exp))×10^(-3).We also obtain R_π|_(LCSR-u)=0.68_(-0.09)^(+0.10)and R_π|_(LCSR-R)=0.65_(-0.11)^(+0.13),both of which agree with the lattice QCD predictions.Thus,HQEFT provides a useful framework for studying B meson decays.Moreover,by using the right-handed correlator,the twist-2 terms are dominant in TFF f^+(q^2),as their contribution is over^97%in the whole q^2 region,while the large twist-3 uncertainty of the conventional correlator is greatly suppressed.Hence,the LCSR-R predictions can be used to test the properties of the various models for the pion twist-2 distribution amplitudes.
