arXiv subjects

Sudeepan Datta

Publications and source records attributed to Sudeepan Datta.

5 recordsLinked to original sources

arXiv2026

Universal Two-Loop Current--Current Renormalization of Four-Fermion Operators

The complete one- and two-loop gauge and scalar current--current contributions to the running of arbitrary dimension-six four-fermion operators are reported. The results are obtained in a basis-independent and renormalization-scheme-agnostic fashion and are valid for arbitrary gauge groups. The complete gauge and scalar contributions, including the genuine one- and two-loop poles, counterterm insertions, wave-function renormalization, finite evanescent insertions, diagram multiplicities, and the associated color, charge and Yukawa factors are provided for the most general renormalizable Lagrangian with gauge and scalar interactions. The results enable the derivation of leading- and next-to-leading-order current--current anomalous-dimension matrices for arbitrary Effective Field Theories (EFTs) and constitute a significant step toward the complete two-loop renormalization of general EFTs.

hep-ph↗

arXiv2024

Three loop QCD corrections to the heavy-light form factors: fermionic contributions

We present analytic results for three-loop fermionic corrections to the heavy-light form factors in perturbative quantum chromodynamics. Specifically, we present all light quark contributions and contributions from two heavy quark loops. We use the method of differential equations to compute all relevant three-loop master integrals. The results for all these contributions are expressed in terms of harmonic polylogarithms and generalized harmonic polylogarithms.

hep-ph↗

arXiv2023

Three loop QCD corrections to the heavy-light form factors in the color-planar limit

We present the analytic expressions for the color-planar contributions to the heavy-light form factors at three loops in perturbative QCD. These form factors play an important role in the precision predictions of various observables in top quark and flavour physics. We compute the master integrals using the method of differential equations. We perform the ultraviolet renormalization for all the appearing fields and parameters. The analytic results for the renormalized form factors are expressed in terms of generalized harmonic polylogarithms. We also study the Sudakov behaviour of these form factors in the asymptotic limit, which enables us to obtain the complete logarithmic three-loop and partial four-loop contributions.

hep-ph↗

arXiv2022

FeynGKZ: a Mathematica package for solving Feynman integrals using GKZ hypergeometric systems

In the Lee-Pomeransky representation, Feynman integrals can be identified as a subset of Euler-Mellin integrals, which are known to satisfy Gel'fand-Kapranov-Zelevinsky (GKZ) system of partial differential equations. Here we present an automated package to derive the associated GKZ system for a given Feynman diagram and solve it in terms of hypergeometric functions using two equivalent algorithms, namely the triangulation method and the Gröbner deformation method. We present our code in the form of a Mathematica package FeynGKZ.wl which requires the softwares polymake, Macaulay2 and TOPCOM, and the packages AMBRE and Olsson.wl as dependencies. As applications of the package, we find series solutions to the GKZ systems of several one-loop and two-loop Feynman integrals. These are included in the file Examples.nb that can be downloaded along with the package from https://github.com/anant-group/FeynGKZ.

hep-th↗

arXiv2019

Quadratic and quartic integrals using the method of brackets

We use the method of brackets to evaluate quadratic and quartic type integrals. We recall the operational rules of the method and give examples to illustrate its working. The method is then used to evaluate the quadratic type integrals which occur in entries 3.251.1,3,4 in the table of integrals by Gradshteyn and Ryzhik and obtain closed form expressions in terms of hypergeometric functions. The method is further used to evaluate the quartic integrals, entry 2.161.5 and 6 in the table. We also present generalization of both types of integrals with closed form expression in terms of hypergeometric functions.

math-ph↗