arXiv subjects

Amol Pawar

Publications and source records attributed to Amol Pawar.

4 recordsLinked to original sources

arXiv2024

Unraveling Gluon TMDs in $J/ψ$ and Pion production at the EIC

We investigate the azimuthal asymmetries such as $\cos2{ϕ_T}$ and Sivers symmetry for $J/ψ$ and $π^\pm$ production in electron-proton scattering, focusing on scenarios where the $J/ψ$ and the pion are produced in an almost back-to-back configuration. The electron is unpolarized, while the proton can be unpolarized or transversely polarized. For the $J/ψ$ formation, we use non-relativistic QCD (NRQCD), while $π^\pm$ is formed due to parton fragmentation. In this kinematics, we utilize the transverse momentum-dependent factorization framework to calculate the cross sections and asymmetries. We consider both quark and gluon-initiated processes and show that the gluon contribution dominates. We provide numerical estimates of the upper bounds on the azimuthal asymmetries, as well as employ a Gaussian parametrization for the gluon transverse momentum distributions (TMDs), within the kinematical region accessible by the upcoming Electron-Ion Collider (EIC).

hep-ph↗

arXiv2024

TMD evolution effect on $\cos2ϕ$ azimuthal asymmetry in a back-to-back production of $J/ψ$ and jet at the EIC

A back-to-back semi-inclusive $J/ψ+ jet$ production is a promising process to study gluon transverse momentum distribution (TMDs) at the future electron-ion collider (EIC). A back-to-back configuration allows a higher transverse momentum for $J/ψ$. We present an extension of a previous work where we studied $\cos2ϕ$ azimuthal asymmetry within the TMD factorization framework for this process. We present and compare the effect of TMD evolution on the asymmetry, in two approaches that differ in the parameterization of the perturbative tails of the TMDs and the non-perturbative factors. We show that the asymmetry depends on the parameterizations of the non-perturbative Sudakov factors in the larger $b_T$ region and on the perturbative part of the evolution kernel. We use NRQCD to estimate the $J/ψ$ production and show the effect of using different long-distance matrix element (LDME) sets. Overall, the asymmetry after incorporating TMD evolution is small, but increases with the transverse momentum imbalance of the $J/ψ$-jet pair.

hep-ph↗

arXiv2023

Azimuthal asymmetries in $D$-meson and jet production at the EIC

We study the azimuthal asymmetries in back-to-back leptoproduction of $D$-meson and jet to probe the gluon TMDs in an unpolarized and transversely polarized electron-proton collision at the kinematics of EIC. We give predictions for unpolarized cross-sections within the TMD factorization framework. In $D$-meson and jet formation, the only leading order contribution comes from the photon gluon fusion process. We give numerical estimates of the upper bound on the azimuthal asymmetries with the saturation of positivity bounds; also, we present the asymmetries using a Gaussian parameterization of TMDs. We obtain sizable asymmetries in the kinematics that will be accessible at EIC.

hep-ph↗

arXiv2022

$\cos2ϕ_t$ azimuthal asymmetry in back-to-back $J/ψ$-jet production in $e~p\rightarrow e~J/ψ~Jet~ X$ at the EIC

In this article, we investigate the $\cos2ϕ_t$ azimuthal asymmetry in $e ~p\rightarrow e ~J/ψ~Jet~ X$, where the $J/ψ$-jet pair is almost back-to-back in the transverse plane, within the framework of the generalized parton model(GPM). We use non-relativistic QCD(NRQCD) to calculate the $J/ψ$ production amplitude and incorporate both color singlet(CS) and color octet(CO) contributions to the asymmetry. We estimate the asymmetry using different parameterizations of the gluon TMDs in the kinematics that can be accessed at the future electron-ion collider (EIC) and also investigate the impact of transverse momentum dependent (TMD) evolution on the asymmetry. We present the contributions coming from different states to the asymmetry in NRQCD.

hep-ph↗