Quark loop contribution to BFKL evolution: Running coupling and leading-N_f NLO intercept

Heribert Weigert (University of Bielefeld); Yuri V. Kovchegov (The Ohio State University)

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Quark loop contribution to BFKL evolution: Running coupling and leading-N_f NLO intercept

Yuri V. Kovchegov (The Ohio State University), Heribert Weigert (University of Bielefeld)

High Energy Physics - Phenomenology · Submitted 6 Dec 2006

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim We obtain the leading-N_f contribution to the NLO BFKL kernel in transverse momentum space and use it to calculate the leading-N_f contribution to the NLO BFKL pomeron intercept for the unintegrated gluon distribution.

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arXiv IDhep-ph/0612071 (version 2)

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CitationHeribert Weigert (University of Bielefeld), Yuri V. Kovchegov (The Ohio State University). "Quark loop contribution to BFKL evolution: Running coupling and leading-N_f NLO intercept." arXiv:hep-ph/0612071 (2006). https://pith.science/paper/ET6XJPW2

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What the abstract itself states, as probabilities: claims first 0.05 · states limitation 0.22 · human participants 0.01 · controlled comparison 0.03 · randomized assignment 0.01 · states quantitative result 0.10 · compares with prior results 0.97 · mentions code or data availability 0.02.

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We study the sea quark contribution to the BFKL kernel in the framework of Mueller's dipole model using the results of our earlier calculation. We first obtain the BFKL equation with the running coupling constant. We observe that the ``triumvirate'' structure of the running coupling found previously for non-linear evolution equations is preserved for the BFKL equation. In fact, we rederive the equation conjectured by Levin and by Braun, albeit for the unintegrated gluon distribution with a slightly unconventional normalization. We obtain the leading-N_f contribution to the NLO BFKL kernel in transverse momentum space and use it to calculate the leading-N_f contribution to the NLO BFKL pomeron intercept for the unintegrated gluon distribution. Our result agrees with the well-known results of Camici and Ciafaloni and of Fadin and Lipatov. We show how to translate this intercept to the case of the quark dipole scattering amplitude and find that it maps onto the expression found by Balitsky.

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What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	We study the sea quark contribution to the BFKL kernel in the framework of Mueller's dipole model using the results of our earlier calculation.	contribution 0.90	0.78	0.04	asserted 0.95
s1	We first obtain the BFKL equation with the running coupling constant.	method 0.51	0.94	0.05	asserted 1.00
s2	We observe that the ``triumvirate'' structure of the running coupling found previously for non-linear evolution equations is preserved for the BFKL equation.	result 0.98	0.87	0.14	asserted 1.00
s3	In fact, we rederive the equation conjectured by Levin and by Braun, albeit for the unintegrated gluon distribution with a slightly unconventional normalization.	result 0.86	0.91	0.08	asserted 0.99
s4	We obtain the leading-N_f contribution to the NLO BFKL kernel in transverse momentum space and use it to calculate the leading-N_f contribution to the NLO BFKL pomeron intercept for the unintegrated gluon distribution.	contribution 0.67	0.96	0.43	asserted 1.00
s5	Our result agrees with the well-known results of Camici and Ciafaloni and of Fadin and Lipatov.	result 0.90	0.58	0.18	asserted 1.00
s6	We show how to translate this intercept to the case of the quark dipole scattering amplitude and find that it maps onto the expression found by Balitsky.	result 0.79	0.94	0.22	asserted 1.00

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 1.00.

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The paper

Original abstract

We study the sea quark contribution to the BFKL kernel in the framework of Mueller's dipole model using the results of our earlier calculation. We first obtain the BFKL equation with the running coupling constant. We observe that the ``triumvirate'' structure of the running coupling found previously for non-linear evolution equations is preserved for the BFKL equation. In fact, we rederive the equation conjectured by Levin and by Braun, albeit for the unintegrated gluon distribution with a slightly unconventional normalization. We obtain the leading-N_f contribution to the NLO BFKL kernel in transverse momentum space and use it to calculate the leading-N_f contribution to the NLO BFKL pomeron intercept for the unintegrated gluon distribution. Our result agrees with the well-known results of Camici and Ciafaloni and of Fadin and Lipatov. We show how to translate this intercept to the case of the quark dipole scattering amplitude and find that it maps onto the expression found by Balitsky.

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17 arXiv papers cite this in 25 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

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Uses its method or tool 5 papers

To incorporate small-$x$ evolution effects, we obtain the quark dipole $S$-matrix $S_x_g(r_⊥)$ by solving the rcBK evolution equation [ref] using the modified McLerran–Venugopalan model [ref] as the initial condition at $x_0=0.01$: [equation] We use $γ=1.118$ and $Λ=0.24$ GeV, as determined from a fit to the inclusive DIS structure functions measured at HERA [ref] .

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The other parameterization for the dipole scattering matrix is the solution of the running-coupling Balitsky-Kovchegov (rcBK) equation [ref] , with the modified McLerran-Venugopalan (MV) [ref] model as the initial condition [equation] with $γ=1.118$, $Λ= 0.241$ GeV, and $Q_s0,p^2=0.16$ GeV$^2$ at $x_0=0.01$.

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Numeric analysis To numerically study the harmonic coefficients $⟨cosnϕ⟩$ in LJC, we employ the GBW model [ref] and the solution of the running-coupling Balitsky-Kovchegov (rcBK) equation [ref] for the dipole S-matrix $S_x(r_⊥)$.

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This is the most natural choice and is also consistent with recent NLO calculations [ref] .

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