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Binesh Mohan

Publications and source records attributed to Binesh Mohan.

4 recordsLinked to original sources

A baryon-calibrated unified quark-diquark effective mass formalism for heavy multiquarks

We present a unified framework for heavy tetraquark and pentaquark systems within the quark-diquark effective mass formalism, extending its baryon-calibrated construction to multiquark states without introducing sector-dependent parameters. Intra-diquark color-spin correlations are encoded in effective diquark masses fixed from baryon spectroscopy, while the inter-cluster chromomagnetic scale, independently determined from vector-pseudoscalar meson splittings, is propagated unchanged to exotic configurations, ensuring residual one-gluon exchange dynamics only between composite color sources. Within this framework, we compute the complete spectra for both $\bar{\mathbf{3}}_c\otimes\mathbf{3}_c$ and $\mathbf{6}_c\otimes\bar{\mathbf{6}}_c$ configurations in tetraquarks, whereas the pentaquark analysis focuses on the dominant $\bar{\mathbf{3}}_c\otimes\bar{\mathbf{3}}_c\otimes\bar{\mathbf{3}}_c$ clustering. Heavy-quark spin symmetry and flavor-symmetry breaking across light, charm, and bottom sectors emerge naturally through the explicit $1/(m_{D_1}m_{D_2})$ scaling of the calibrated couplings. The resulting spectra exhibit a coherent dynamical hierarchy spanning baryons and multiquark states. Established exotic candidates are reproduced within hadronic uncertainties, while the unified calibration enables quantitative predictive control across flavor sectors. The framework thus provides a parameter-economical, systematically constrained baseline with unified dynamical consistency for heavy multiquark spectroscopy.

hep-ph

Quark-diquark effective mass formalism for heavy baryon spectroscopy

We develop a quark-diquark effective mass formalism for heavy-flavor baryon spectroscopy and apply it to the $J^P = \tfrac{1}{2}^+$ and $J^P = \tfrac{3}{2}^+$ spectra across the singly, doubly, and triply heavy sectors. The analysis is carried out in two complementary scenarios: Scenario I treats all quark-quark diquark channels dynamically, while Scenario II restricts the dynamics to scalar and axial-vector diquarks, providing a more selective and physically transparent description. Constituent quark masses, effective diquark masses, and chromomagnetic couplings are extracted from known heavy-baryon masses, with the couplings determined solely by the quark content of each state and no sector-dependent adjustment introduced. A mass-dependent binding term is implemented to account for spin-independent chromoelectric effects and to describe the transition from chromomagnetic to color-Coulomb dominance across the light-to-heavy quark regime, ensuring consistency with heavy-quark spin symmetry in the heavy-quark limit. The resulting predictions are in good agreement with available experimental measurements and lattice QCD results across both charm and bottom sectors. The extracted diquark parameters remain stable across all heavy-flavor sectors, establishing the present framework as a symmetry-constrained spectroscopic baseline for heavy-baryon structure.

hep-ph

Systematic study of light and charm meson M1 radiative transitions

Motivated by recent experimental advancements in the study of radiative decays of charmed mesons, we investigate the magnetic (transition) moments of vector mesons by applying the effective mass scheme, obtained from the one-gluon exchange interaction between quark-antiquark pairs. By incorporating high-precision experimental data from both heavy and light flavor sectors, we accurately account for the strong hyperfine interaction contributions to the quark and antiquark masses within mesons. We calculate the $V \to P$ effective transition magnetic moments to reliably predict M1 decay widths. Furthermore, to enhance the completeness of our analysis, we employ the non-relativistic potential model to calculate bound state isomultiplet masses and to predict the M1 decay widths of charmed mesons. Additionally, scale-dependent effects in both the effective mass scheme and the potential model are systematically analyzed and interpreted, emphasizing the decisive role of higher-order QCD corrections in determining M1 decay widths.

hep-ph

Screening of quark charge and mixing effects on transition moments and M1 decay widths of baryons

Motivated by the precision measurements of heavy flavor baryon masses, we analyze the modification of quark charge by employing the screening effect inside the baryon. In addition, we calculate the isospin mass splitting up to charmed baryons employing isospin symmetry breaking. Consequently, we obtain the masses, magnetic moments, and transition moments of $J^P=\frac{1}{2}^+$ and $\frac{3}{2}^+$ baryons to predict radiative decay widths for $\frac{1}{2}^{\prime +} \to \frac{1}{2}^+$ and $\frac{3}{2}^+\to \frac{1}{2}^{(\prime)+}$ transitions. Finally, we include the effects of state mixing in flavor degenerate baryon magnetic and transition moments, as well as M1 transition decay widths.

hep-ph