Searcharxiv⌕ Search

arXiv subjects

Harleen Dahiya

Publications and source records attributed to Harleen Dahiya.

At least 73 records · Page 4Linked to original sources
arXiv2023

Generalized parton distributions for the lowest-lying octet baryons

We have presented a pathway to map the internal structure of lowest-lying octet baryons by using one-loop quantum fluctuations of a fermion state in Yukawa theory. The structural interpretation of baryons carrying different amount of strange content has been exemplified by employing a quark-scalar diquark model for studying the Generalized Parton Distributions (GPDs) among the members of octet baryons. Different possible combinations of quark-scalar diquark pairs have been considered. The quark helicity independent chiral even GPDs in momentum as well as impact parameter space have been studied for purely transverse momentum transfer (zero skewness). We have also extended our calculations to explore and visualize the distinct behavior of charge distributions in coordinate space as well as charge densities in impact parameter space. Furthermore, magnetization density in impact parameter space has also been investigated. Quantitative as well as qualitative analysis of all the distributions has been carried out.

hep-ph↗
arXiv2023

Investigation on the higher twist TMD $h_3$ for proton in the light-front quark-diquark model

The higher twist T-even transverse momentum dependent distribution (TMD) $h_3(x, {\bf p_\perp^2})$ for the proton has been examined in the light-front quark-diquark model (LFQDM). By deciphering the unintegrated quark-quark correlator for semi-inclusive deep inelastic scattering (SIDIS), we have derived explicit equations of the TMD for both the scenarios when the diquark is a scalar or a vector. Average as well as average square transverse momenta have been computed for this TMD. Additionally, we have discussed its transverse momentum dependent parton distribution function (TMDPDF) $h_3(x)$.

hep-ph↗
arXiv2023

Analysis of the higher twist GTMD $F_{31}$ for proton in the light-front quark-diquark model

In the light-front quark-diquark model (LFQDM), the higher twist generalized transverse momentum dependent distribution (GTMD) $F_{31}(x, {\bf p_\perp},{\bf Δ_\perp})$ for the proton has been analyzed. We have derived the GTMD overlap equation by the analysis of GTMD correlator, employing the light-front wave functions in both the scalar and vector diquark situations. With the relevant 2-D and 3-D figures, the behavior of GTMD $F_{31}(x, {\bf p_\perp},{\bf Δ_\perp})$ with variations in its variables has been illustrated. Further, on applying the transverse momentum dependent distribution (TMD) limit on GTMD $F_{31}(x, {\bf p_\perp},{\bf Δ_\perp})$, the expression of TMD $f_3(x, {\bf p_\perp})$ has been obtained.

hep-ph↗
arXiv2023

Axial-vector form factors of the light, singly and doubly charmed baryons in the chiral quark constituent model

The axial-vector form factors of the light, singly and doubly charmed baryons are investigated in the framework of $SU(4)$ chiral constituent quark model. The axial-vector form factors having physical significance correspond to the generators of the $SU(4)$ group with flavor singlet $λ^{0}$, flavor isovector $λ^{3}$, flavor hypercharge $λ^{8}$ and flavor charmed $λ^{15}$ combinations of axial-vector current at zero momentum transfer. In order to further understand the $Q^2$ dependence of these charges, we have used the conventionally established dipole form of parametrization.

hep-ph↗
arXiv2023

Sub-leading twist transverse momentum dependent parton distributions in the light-front quark-diquark model

In this study, the T-even sub-leading twist transverse momentum dependent distributions (TMDs) of proton in the light-front quark-diquark model (LFQDM) have been investigated. We have derived the overlap form of the light-front wave functions (LFWFs) for the sub-leading twist proton TMDs by detangling the un-integrated quark-quark correlator for the semi-inclusive deep inelastic scattering (SIDIS). We have obtained the explicit expressions of TMDs for both the cases of the diquark being a scalar or a vector and analysed their relationships with leading twist TMDs within the same model. Average transverse momenta and average square transverse momenta for the TMDs have been tabulated and compared with the results from the light-front bag model and the light-front constituent quark model (LFCQM). In addition to this, we have also compared our results for the PDF $e(x)$ with the recent CLAS collaboration results.

hep-ph↗
arXiv2023

Axial-vector charges of the spin $\frac{1}{2}^+$ and spin $\frac{3}{2}^+$ light and charmed baryons in the SU(4) chiral quark constituent model

Following the first clear evidence of the presence of intrinsic charm contribution in the proton, the axial-vector charges of the light and charmed baryons are investigated in the framework of $SU(4)$ chiral constituent quark model after including the explicit contributions from the $u\bar u $, $d\bar d $, $s\bar s $ and $c\bar c $ fluctuations. The axial-vector charges having physical significance correspond to the generators of the $SU(4)$ group with flavor singlet $λ^0$, flavor isovector $λ^3$, flavor hypercharge $λ^8$ and flavor charmed $λ^{15}$ combinations of axial-vector current at zero momentum transfer. In contemplation to further understand the $Q^2$ dependence of these charges, we have used the conventionally established dipole form of parametrization. The baryons considered here are the spin $\frac{1}{2}^+$ and spin $\frac{3}{2}^+$ multiplets decomposed further depending on the charm content of baryons.

hep-ph↗
arXiv2023

Non-perturbative Generation of Light Antiquark Flavor Asymmetry in Proton

We compute the light antiquark flavor asymmetry in the proton using the Chiral Quark Model ($χ_{\rm QM}$). The distribution functions for the light antiquarks $\bar{d}(x)$ and $\bar{u}(x)$ have been extracted with the help of experimental data from NuSea/E866 and HERMES for the Bjorken$-x$ range $0.015 < x < 0.35$ as well from the most recent SeaQuest data for an extended $x$ range $0.13 < x < 0.45$. Our results on the $\bar{d}(x)-\bar{u}(x)$, $\frac{\bar{d}(x)}{\bar{u}(x)}$ and Gottfried Integral $I_G$ are in agreement with the experimental data and confirm the presence of enhanced $\bar{d}$ sea whose origin is purely non-perturbative based on chiral symmetry breaking in QCD.

hep-ph↗
arXiv2023

Twist-4 T-even proton TMDs in the light-front quark-diquark model

We have dealt with the twist-4 T-even transverse momentum-dependent parton distributions (TMDs) for the case of proton in the light-front quark-diquark model (LFQDM). By decoding the unintegrated quark-quark correlator for the semi-inclusive deep inelastic scattering (SIDIS), we have specifically obtained the overlap form for the unpolarized \bigg($f_{3}^ν(x, {\bf p_\perp^2})$\bigg), longitudinally polarized \bigg($ g_{3L}^ν(x, {\bf p_\perp^2}),~h_{3L}^{\perpν}(x, {\bf p_\perp^2})$\bigg) and transversely polarized \bigg( ${g}^{ν}_{3T}(x, {\bf p_\perp^2}),~{h}^{ν}_{3T}(x, {\bf p_\perp^2})$ and ${h}^{ν\perp}_{3T}(x, {\bf p_\perp^2})$\bigg) proton TMDs. We have provided the explicit expressions for both the cases of the diquark being a scalar or a vector. Average transverse momenta and the average square transverse momenta for the TMDs have been calculated and the results have been tabulated with corresponding leading twist TMDs. In addition, the value of average transverse momentum and average square transverse momentum for TMD ${f}^{ν}_3(x, {\bf p_\perp^2})$ has been compared with the available light-front constituent quark model (LFCQM) results. From TMDs, we have also obtained and discussed the transverse momentum-dependent parton distribution functions (TMDPDFs). The model relations of the twist-4 T-even TMDs with the available leading twist T-even TMDs have also been obtained.

hep-ph↗
arXiv2022

T-odd quark-gluon-quark correlation function in the light-front quark-diquark model

We have scrutinized the transverse momentum dependent quark-gluon-quark correlation function. We have utilized the light-front quark-diquark model to study the time-reversal-odd interaction-dependent twist-3 gluon distributions which we have obtained from the disintegration of the transverse momentum dependent quark-gluon-quark correlator. Specifically, we have studied the behavior of $\tilde{e}_{L}$ and $\tilde{e}_{T}$ while considering our diquark to be an axial-vector.

hep-ph↗
arXiv2021

Extending light-front holographic QCD using the 't Hooft Equation

We show the 't Hooft Equation and the light-front holographic Schrödinger Equation are complementary to each other in governing the transverse and longitudinal dynamics of colour confinement in quark-antiquark mesons. Together, they predict remarkably well the light, heavy-light and heavy-heavy meson spectroscopic data. The universal emerging hadronic scale of light-front holography, $κ\approx 0.5$ GeV, controls the transverse dynamics of confinement in all mesons. In heavy-heavy mesons, it also coincides numerically with the 't Hooft coupling which governs longitudinal confinement, thus reflecting the restoration of manifest 3-dimensional rotational symmetry

hep-ph↗
arXiv2020

Light-front holographic $ρ$-meson distributions in the momentum space

We present the leading-twist quark transverse momentum-dependent parton distribution functions (TMDs) for the spin-1 target, such as the $ρ$-meson, in the light-front framework. Specifically, we predict the TMDs in the light-front holographic model and compare with the light-front quark model predictions. We obtain the TMDs using the overlap of the light-front wave functions. We evaluate the ${\bf k}_\perp$ moments upto second order and compare with the available theoretical predictions. Further, we analyze the leading-twist parton distribution functions (PDFs) of the $ρ$-meson in the light-front holographic model which are found to be in accord with the Nambu-Jona-Lasinio (NJL) model and the light-front quark model predictions. We further study the QCD evolution of the PDFs. The positivity bounds on the TMDs and the PDFs are also discussed. We also present the quark spin densities in the transverse momentum plane for different polarization configurations of the quark and the $ρ$-meson target.

hep-ph↗
arXiv2020

Tomography of light mesons in light-cone quark model

We investigate the tomographical structure of pion and kaon in light cone quark model (LCQM). In particular, we study the parton distribution amplitude (PDA) of pion and kaon. We obtain the parton distribution function (PDF) and the generalized parton distributions (GPDs) of the pion and kaon. The valence quark PDA and PDF of pion, after QCD evolution, are found to be consistent with the data from the E791 and the E615 experiments at Fermilab, respectively. Further, we investigate the transverse momentum distributions (TMDs) of pion and kaon. We also discuss the unpolarized TMD evolution for pion and kaon in this model.

hep-ph↗
arXiv2019

Study of spin-spin correlations between quark and a spin-$\frac{1}{2}$ particle

We study the correlation between the fermion composite system and quark spins by using the light-cone quark-diquark model. We do the calculations for $u$-quark and $d$-quark in the fermion system by considering the different polarization configrations of both. The contribution from scalar and axial-vector diquarks is taken into account. The overlap represenation of light-front wavefunctions is used for the calculations. The spin-spin correlations for $u$ and $d$ quarks are presented in transverse impact-parameter plane and transverse momentum plane as well.

hep-ph↗
arXiv2019

Quark Wigner Distributions and GTMDs of Pion in the Light-Front Holographic Model

We investigate the quark Wigner distributions of the pion to reveal the multidimensional picture of pion. We have used the spin improved wave functions of pion deduced from the light-front holographic model of mesons. By using the Fock-state overlap representation, the Wigner distributions of an unpolarized, longitudinally polarized and transversely polarized quark inside the pion are calculated. We have presented the results of transverse Wigner distributions in impact-parameter space as well as in momentum space. In order to understand the role of skewness which gives the longitudinal momentum transfer between the quarks, we study the six-dimensional phase-space distribution: the generalized transverse momentum dependent parton distributions of pion for the case of zero skewness as well as for nonzero value of skewness.

hep-ph↗
arXiv2019

Study of kaon structure using the light-cone quark model

We investigate the various distributions explaining multi-dimensional structure of kaon at the level of its constituents ($u$ and $\bar{s}$) using the light-cone quark model. The overlap form of wavefunctions associated with the light-cone quark model is adopted for the calculations. The generalized parton distributions(GPDs)of $u$ and $\bar{s}$ quarks are presented for the case when the momentum transfer in the longitudinal direction is non-zero. The dependence of kaon GPDs is studied in terms of variation of quark longitudinal momentum fraction, momentum transfer in longitudinal direction and total momentum transfer to the final state of hadron. The transverse impact-parameter dependent GPDs are also studied by taking the Fourier transformation of general GPDs. Further, the quantum phase-space distributions; Wigner distributions are studied for the case of unpolarized, longitudinally-polarized and transversely-polarized parton in an unpolarized kaon. The Wigner distributions are analysed in the transverse impact-parameter plane, the transverse momentum plane and the mixed plane. Further, to get a complete picture of kaon in terms of its valence quarks, the variation of longitudinal momentum fraction carried by quark and antiquark in the generalized transverse momentum-dependent parton distributions (GTMDs) is studied for different values of transverse quark and antiquark momentum $({\bf k}_\perp)$ as well as for different values of momentum transferred to the kaon in transverse direction $({\bf Δ}_\perp)$. This has been done for zero as well as non-zero skewedness representing respectively the absence and presence of momentum transfer to the final state of kaon in longitudinal direction. Furthermore, the possible spin-orbit correlation for $u$ and $\bar{s}$ in kaon is elaborated in context of Wigner distributions and GTMDs.

hep-ph↗
arXiv2019

Transverse momentum dependent parton distributions of pion in the light-front holographic model

Using the light-front holographic model, we study the transverse momentum dependent parton distributions (TMDs) for the case of pion. At leading twist, the unpolarized parton distribution function $ f_{1π}(x,\bfk^{2}) $ and the Boer-Mulders function $ h_{1π}^{\bot}(x,\bfk^{2}) $ are obtained for pion. We calculate both the functions using the light-front holographic model with spin improved wave function and compare the predicted results with available results of other models. In order to provide inputs in predicting future experimental data, a LO evolution is performed from model scale to experimental scale for the case of unpolarized parton distribution function $ f_{1π}(x,\bfk^{2}) $.

hep-ph↗
arXiv2019

Twist-2 Pseudoscalar and Vector Meson Distribution Amplitudes in Light-Front Quark Model with Exponential-type Confining Potential

We study the twist-2 distribution amplitudes (DAs) and the decay constants of pseudoscalar light ($π$, $K$) and heavy ($D$, $D_s$, $B$, $B_s$) mesons as well as the longitudinally and transversely polarized vector light ($ρ$, $K^*$) and heavy ($D^*$, $D_s^*$, $B^*$, $B_s^*$) mesons in the light-front quark model with the Coulomb plus exponential-type confining potential $V_{\rm {exp}} = a + b e^{αr}$ in addition to the hyperfine interaction. We first compute the mass spectra of ground state pseudoscalar and vector light and heavy mesons and fix the model parameters necessary for the analysis, applying the variational principle with the trial wave function up to the first three lowest order harmonic oscillator (HO) wave functions $Φ(x, \textbf{k}_\bot) = \sum_{n=1}^{3} c_n ϕ_{nS}$. We then obtain the numerical results for the corresponding decay constants of light and heavy mesons. We estimate the DAs, analyze their variation as a function of momentum fraction and compute the first six $ξ$-moments of the $B$ and $D$ mesons as well. We compare our results with the available experimental data as well as with the other theoretical model predictions.

hep-ph↗