نتایج جستجو برای: who essential list of drugs
تعداد نتایج: 21216991 فیلتر نتایج به سال:
A particularly simple confinement scenario [1] is available in the minimal Coulomb gauge. It attributes confinement of color to the long range of the color-Coulomb potential Vcoul(R). This quantity is the instantaneous part of the 4-4 component of the gluon propagator, Dμν(x) ≡ 〈gAμ(x) gAν(0)〉, namely D44(x, t) = Vcoul(|x|)δ(t) +P (x, t). The vacuum polarization term P (x, t) is less singular t...
The motion of quark is studied in a confining bag having central color field. The Dirac equation is solved for a quark in such bag and its energy spectrum is found. It is pointed out the possibility to identify the external color field with the background field of gluon condensation. This makes the received energy spectrum of quark useful for comparison with the energy spectrum of hadrons.
A realistic hyperon (Y )-nucleon (N) interaction based on the quark model and the oneboson-exchange potential is constructed. The Nijmegen potential model D with the SU(3) flavor symmetry is modified with a quark exchange interaction at the short-distance, which replaces the short-range repulsive core in the original model. The flavor-spin dependences of the short-range repulsion are qualitativ...
We study the modification of the multiplicity distributions in MLLA due to the presence of a QCD medium. The medium is introduced though a multiplicative constant (fmed) in the soft infrared parts of the kernels of QCD evolution equations. Using the asymptotic ansatz for quark and gluons mean multiplicities 〈nG〉 = e γy and 〈nQ〉 = r e respectively, we study two cases: fixed γ as previously consi...
We considered the quark-meson coupling model for a nucleon. The model describes a nucleon as an MIT bag, in which quarks are coupled to the scalar and the vector mesons. A set of coupled equations for the quark and the meson fields are obtained and are solved in a self-consistent manner. We show that the mass of a dressed MIT bag interacting with σand ω-meson fields differs considerably from th...
We study transverse momentum dependent parton distribution functions (TMDs) with non-local operators in lattice QCD, using MILC/LHPC lattices. We discuss the basic concepts of the method, including renormalization of the gauge link. Results obtained with a simplified operator geometry show visible dipole deformations of spin-dependent quark momentum densities.
A summary of some recent studies in jet physics is given. Topics include leading particle production in light flavor events in e + e − annihilations, an analytical treatment of gluon and quark jets at the next-to-next-to-next-to-leading order (3NLO), and various studies performed at LEP and HERA involving separated gluon and quark jets. 1 Leading particle production in separated light quark eve...
It is presented a critical consideration of all unusual properties of the scalar a 0 (980) and f 0 (980)-mesons in the four-quark, two-quark and molecular models. The arguments are adduced that the four-quark model is more preferable. It is discussed the complex of experiments that could finally resolve this issue.
Expressions for the nucleon wave functions in the covariant spectator theory (CST) are derived. The nucleon is described as a system with a off-mass-shell constituent quark, free to interact with an external probe, and two spectator constituent quarks on their mass shell. Integrating over the internal momentum of the on-mass-shell quark pair allows us to derive an effective nucleon wave functio...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید