Deuteron form factors in the light-cone quantum mechanics ‘‘good’’ component approach

1993 ◽  
Vol 48 (5) ◽  
pp. 2182-2189 ◽  
Author(s):  
L. L. Frankfurt ◽  
T. Frederico ◽  
M. Strikman
Keyword(s):  
Quantum Mechanics ◽  
Light Cone ◽  
Form Factors ◽  
Component Approach

scholarly journals Light-cone sum rules for proton decay

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Ulrich Haisch ◽  
Amando Hala
Keyword(s):  
Lattice Qcd ◽  
Light Cone ◽  
Sum Rules ◽  
State Of The Art ◽  
Form Factors ◽  
Baryon Number ◽  
Proton Decay ◽  
Matrix Elements ◽  
Decay Channels ◽  
Systematic Uncertainties

Abstract We estimate the form factors that parametrise the hadronic matrix elements of proton-to-pion transitions with the help of light-cone sum rules. These form factors are relevant for semi-leptonic proton decay channels induced by baryon-number violating dimension-six operators, as typically studied in the context of grand unified theories. We calculate the form factors in a kinematical regime where the momentum transfer from the proton to the pion is space-like and extrapolate our final results to the regime that is relevant for proton decay. In this way, we obtain estimates for the form factors that show agreement with the state-of-the-art calculations in lattice QCD, if systematic uncertainties are taken into account. Our work is a first step towards calculating more involved proton decay channels where lattice QCD results are not available at present.

scholarly journals Space- and time-like electromagnetic pion form factors in light-cone pQCD

2010 ◽  
Vol 693 (2) ◽  
pp. 102-107 ◽  
Author(s):  
Jiunn-Wei Chen ◽  
Hiroaki Kohyama ◽  
Kazuaki Ohnishi ◽  
Udit Raha ◽  
Yue-Long Shen
Keyword(s):  
Light Cone ◽  
Form Factors ◽  
Space And Time

scholarly journals ANALYSIS OF THE $B \to K^*_2(1430), a_2(1320), f_2(1270)$ FORM-FACTORS WITH LIGHT-CONE QCD SUM RULES

2011 ◽  
Vol 26 (37) ◽  
pp. 2761-2782 ◽  
Author(s):  
ZHI-GANG WANG
Keyword(s):  
Experimental Data ◽  
Light Cone ◽  
B Meson ◽  
Sum Rules ◽  
Form Factors ◽  
Distribution Amplitude ◽  
Qcd Sum Rules ◽  
Line Shapes ◽  
The Future

In this paper, we study the [Formula: see text] form-factors with the light-cone QCD sum rules, where the B-meson light-cone distribution amplitudes are used. In calculations, we observe that the line-shapes of the B-meson light-cone distribution amplitude ϕ+(ω) have significant impacts on the values of the form-factors, and expect to obtain severe constraints on the parameters of the B-meson light-cone distribution amplitudes from the experimental data in the future.

scholarly journals Nucleon’s energy–momentum tensor form factors in light-cone QCD

2020 ◽  
Vol 80 (2) ◽  
Author(s):  
K. Azizi ◽  
U. Özdem
Keyword(s):  
Perturbation Theory ◽  
Lattice Qcd ◽  
Chiral Perturbation Theory ◽  
Light Cone ◽  
Energy Momentum Tensor ◽  
Form Factors ◽  
Momentum Tensor ◽  
Tensor Form ◽  
Chiral Perturbation ◽  
Theoretical Predictions

Abstract We use the energy–momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon’s interpolating field and use the distribution amplitudes (DAs) of the nucleon with two sets of the numerical values of the main input parameters entering the expressions of the DAs. The directly obtained results from the sum rules for the form factors are reliable at $$ Q^2\ge 1$$Q2≥1 GeV$$^2 $$2: to extrapolate the results to include the zero momentum transfer squared with the aim of estimation of the related static physical quantities, we use some fit functions for the form factors. The numerical computations show that the energy–momentum tensor form factors of the nucleon can be well fitted to the multipole fit form. We compare the results obtained for the form factors at $$ Q^2=0 $$Q2=0 with the existing theoretical predictions as well as experimental data on the gravitational form factor d$$_1^q(0)$$1q(0). For the form factors M$$_2^q (0)$$2q(0) and J$$^q(0)$$q(0) a consistency among the theoretical predictions is seen within the errors: our results are nicely consistent with the Lattice QCD and chiral perturbation theory predictions. However, there are large discrepancies among the theoretical predictions on d$$_1^q(0)$$1q(0). Nevertheless, our prediction is in accord with the JLab data as well as with the results of the Lattice QCD, chiral perturbation theory and KM15-fit. Our fit functions well define most of the JLab data in the interval $$ Q^2\in [0,0.4]$$Q2∈[0,0.4] GeV$$^2 $$2, while the Lattice results suffer from large uncertainties in this region. As a by-product, some mechanical properties of the nucleon like the pressure and energy density at the center of nucleon as well as its mechanical radius are also calculated and their results are compared with other existing theoretical predictions.

Sign in / Sign up

Export Citation Format

Share Document