Particle Creation Cosmology in f(Q,L m ) Gravity: Bayesian Constraints from Recent Cosmological Observations

Particle creation has emerged as a physically motivated mechanism for explaining the late-time accelerated expansion of the Universe without invoking an explicit dark energy component. In this work, we investigate particle creation cosmology within the framework of [Formula: see text] gravity, where [Formula: see text] is the non-metricity scalar and [Formula: see text] is the matter Lagrangian. Considering two linear forms of the gravitational Lagrangian, we derive the corresponding modified Friedmann equations and obtain analytical expressions for the Hubble parameter by incorporating a phenomenological particle creation rate. The viability of the proposed model is examined through Bayesian MCMC analysis using the Pantheon+SH0ES Type Ia supernova, cosmic chronometer, and DESI DR2 baryon acoustic oscillation datasets. The observational constraints show that the physically viable model successfully reproduces the observed transition from an early decelerated phase to the present accelerated expansion. For the combined Pantheon+SH0ES and DESI DR2 BAO dataset, we obtain [Formula: see text] [Formula: see text], [Formula: see text], and [Formula: see text] [Formula: see text]. The inclusion of cosmic chronometer data produces nearly unchanged constraints, yielding [Formula: see text] [Formula: see text], [Formula: see text], and [Formula: see text] [Formula: see text]. The evolution of the Hubble, deceleration, effective equation of state, and jerk parameters further demonstrates consistency with the observed expansion history while allowing small deviations from the standard [Formula: see text]CDM scenario at intermediate redshifts. The statistical comparison with [Formula: see text]CDM indicates that the additional parameter of the viable model is not strongly required by the present datasets. These results indicate that particle creation in [Formula: see text] gravity provides a viable phenomenological framework for describing the late-time dynamics of the Universe.