A model is suggested to interpret nucleon electromagnetic form factors both in space and time-like regions and to describe the existing data. It implies quarks to be colorless in the region of high ...intensity chromo-electromagnetic gluon field inside the nucleon.
Starting from the gauge invariant effective action in the quasi-multi-Regge kinematics (QMRK), we obtain the effective reggeized gluon (R)–particle (P) vertices of the following types:
R
P
P
,
R
R
P
...,
R
R
P
P
,
R
P
P
P
,
R
R
P
P
P
, and
R
P
P
P
P
, where the
on-mass-shell particles are gluons, or sets of gluons with small invariant masses. The explicit expressions satisfying the Bose-symmetry and gauge invariance conditions are obtained. As a comment to the Feynman rules for derivation of the amplitudes in terms of effective vertices we present a “vocabulary” for practitioners.
Oligotrophic bogs' runoff effect on surface waters Berezin, A E; Zakharova, E A; Parshina, N V ...
IOP conference series. Earth and environmental science,
11/2019, Letnik:
400, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The removal of organic matter, including carbon, from oligotrophic bogs is determined by the amount of decomposed organic matter in bog waters and the runoff intensity. This process has a pronounced ...seasonal dynamics and is determined by weather conditions and characteristics of the bog runoff. The maximum watering is observed in the spring during snow thawing and in the autumn due to abundant precipitation and reduced evaporation. The amount of organic matter in bog water is determined by the air temperature of the previous period. Thus, the maximum carbon runoff from the bogs is possible in May-June and September, and the situation can vary considerably over the years, the weather being taken into account.
The process of electron–positron annihilation into proton–antiproton pair is considered within the vicinity of ψ(3770) resonance. The interference between the pure electromagnetic intermediate state ...and the ψ(3770) state is evaluated. It is shown that this interference is destructive and the relative phase between these two contributions is large (ϕ0≈250°).
The paper investigates contributions of
γ
,
Z
,
W
and ghost intermediate states of box-type to the parity-violating Møller scattering asymmetry up to two-loop level. Using the Yennie–Frautschi–Suura ...factorization form for amplitudes, we demonstrate that QED corrections, with an exception of vacuum-polarization effects, cancel at the asymmetry level. We obtain chiral amplitudes at Born, one-loop and partially at two-loop level: ladder boxes and decorated boxes. Our calculations are relevant for the ultra-precise 11 GeV MØLLER experiment planned at Jefferson Laboratory. The numerical comparison of the two-loop contributions with the experimental accuracy of MØLLER is provided.
We show that the intermediate quarkonium state χc2(P23)(3556) in electron–positron annihilation to proton and antiproton as well as in antiproton–proton annihilation to electron and positron can give ...rise to backward–forward asymmetry. We apply the dispersion relation method, which allows us to express the asymmetry in terms of partial widths of quarkonium decay. The asymmetry dependence on the center of mass energy in the resonance region is presented. Quantitative comparison with similar effects induced in these reactions by QED effects and by the mechanism with neutral Z-boson in the intermediate state is given. We show that the asymmetry arising from the resonance excitation in the intermediate state is of the same order of the asymmetry of pure QED origin (∼10−2) which arises from the interference between initial and final state real photon emission.
We consider an effective method for increasing the total efficiency of relativistic Cherenkov generators, viz., recuperation. It has been found that, for a generator with an efficiency smaller than ...15%, recuperation makes it possible to obtain an increase in the efficiency that exceeds 50% (from 12% to 68%). In generators with initially high efficiency (more than 50%), recuperation may turn out to be ineffective.
The high energy amplitudes of the large angles Møller scattering are calculated in the frame of chiral basis in Born and 1-loop QED level. Taking into account as well the contribution from emission ...of soft real photons the compact relations free from infrared divergences are obtained. The expressions for the contributions to the cross section of individual chiral amplitudes are in agreement with renormalization group predictions.
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