arXiv subjects

Musajan Kadir

Publications and source records attributed to Musajan Kadir.

3 recordsLinked to original sources

arXiv2026

Spin - resolved momentum distributions and vortex evolution in multiphoton pair production within a modified two-level model

We investigate spin-resolved momentum distributions and phase vortices in multiphoton electron-positron pair production within a modified two-level model. This model retains the diagonal spinor inner-product terms neglected in the adiabatic approximation, thereby inducing spin-resolved transverse asymmetries in the momentum distribution. For a circularly polarized pulse, the handedness determines the winding direction of the quantized vortices, whereas for a linearly polarized pulse, the phase distribution exhibits nodal lines rather than quantized vortices. For two time-delayed circularly polarized pulses, the time delay introduces a relative phase that governs the multiphoton interference, which in turn drives the vortex evolution in each spin configuration. These results demonstrate that pulse polarization and time delay enable coherent control over vortex topology in pair production.

hep-ph↗

arXiv2026

Polarization signatures of mixed scalar - pseudoscalar ALP - photon couplings in intense laser pulses

We investigate photon-to-axion-like-particle (ALP) conversion in a finite, linearly polarized laser pulse for a single ALP field with simultaneous scalar-type and pseudoscalar-type couplings to photons. Varying the collision angle between the strong pulse and the probe provides a continuous kinematic scan of the resonant ALP mass. For fixed kinematics in this setting, the scalar-type and pseudoscalar-type ALP conversion amplitudes interfere coherently, making both the photon-to-ALP conversion probability and the polarization rotation depend on the difference between the probe polarization angle $α$ and the coupling angle $θ_g$. Conversion is maximal at $|α-θ_g|=90^\circ$, where the polarization rotation vanishes, while the rotation magnitude peaks at $α-θ_g=45^\circ$ modulo $90^\circ$, where conversion is half-maximal. These complementary polarization-angle dependences provide polarization-resolved signatures of mixed scalar--pseudoscalar photon couplings.

hep-ph↗

arXiv2020

The impact of ATLAS and CMS single differential top-quark pair measurements at $\sqrt{s}=8$ TeV to CTEQ-TEA PDFs

By applying the Error PDF Updating Method, we analyze the impact of the absolute and normalized single differential cross-sections for top-quark pair production data from the ATLAS and CMS experiments at the Large Hadron Collider, at a centre-of-mass energy of $\sqrt{s}= 8$ TeV, on the CT14HERA2 PDFs. We find that the top quark pair single differential distributions provide minor constraints on the CT14HERA2 gluon PDF when the nominal CT14HERA2 inclusive jet production data are included in the fit. Larger constraints on the gluon distribution are present when the jet data are removed (CT14HERA2mJ) and/or when increased weights are given to the top data in the CT14HERA2 fits. The weighted $t\bar t$ data provide significant constraints on the CT14HERA2mJ gluon PDF, that are comparable to those obtained from inclusive jet production data. Furthermore, we examine the top quark mass sensitivity of the top-quark pair single differential distributions.

hep-ph↗