Heavy quarkq¯qmatrix elements in the nucleon from perturbative QCD
نویسندگان
چکیده
منابع مشابه
Heavy Quark q̄q Matrix Elements in the Nucleon from Perturbative QCD
The scalar heavy quark content of the nucleon, Mq = 〈N |mq q̄q|N〉, is relevant for computing the interaction of dark matter candidates with ordinary matter, while Ms is important for predicting the properties of dense matter. We compute Mq in perturbative QCD to O(α 3). As one goes from Mt to Mc the leading order contribution decreases as the number of light quarks is dropping, while the radiati...
متن کاملNucleon Decay Matrix Elements from Lattice QCD
We present a GUT-model-independent calculation of hadron matrix elements for all dimension-six operators associated with baryon number violating processes using lattice QCD. Our results cover all the matrix elements required to estimate the partial lifetimes of (proton,neutron)→(π, K, η) +(ν̄, e, μ) decay modes. We point out the necessity of disentangling two form factors that contribute to the ...
متن کاملPerturbative QCD and Nucleon Structure Functions
We review the basic aspects of the perturbative QCD based on the operator product expansion to analyze the nucleon structure functions in a pedagogical way. We explain the non-trivial relation between the QCD results and the parton model especially to understand the polarized nucleon structure functions which deserve much attentions in recent years. Invited talk at the YITP Workshop on “From Ha...
متن کاملPerturbative QCD Effects in Heavy Meson Decays
The amplitude for the exclusive nonleptonic decay of a heavy meson into two light pseudoscalar mesons is analyzed using the factorization formalism of perturbative QCD for exclusive reactions at large momentum transfer. We show that the leading contribution to such amplitudes is proportional to (rs(Q2) where Q” scales with the heavy meson mass squared. Branching ratios for a few B” decay modes ...
متن کاملPerturbative QCD calculations with heavy quarks
Description of the higher order QCD effects in heavy quark processes is important in view of the improving experimental precision. Ongoing efforts to determine the CKM matrix elements motivate a thorough theoretical description of B meson decays (for a review see ). These studies are made difficult by the complexity of the initial state, however even their conceptually simplest part — perturbat...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review D
سال: 2004
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.70.094028