Algebraic Ansätze for the Poincaré-covariant Bethe-Salpeter wave functions of the pion and kaon are used to calculate their light-front wave functions, parton distribution amplitudes, parton quasidistribution amplitudes, valence parton distribution functions, and parton quasidistribution functions (PqDFs). The light-front wave functions are broad, concave functions, and the scale of flavor-symmetry violation in the kaon is roughly 15%, being set by the ratio of emergent masses in the $s$- and $u$-quark sectors. Parton quasidistribution amplitudes computed with longitudinal momentum $P_z=1.75\mathrm{GeV}$ provide a semiquantitatively accurate representation of the objective parton distribution amplitude, but even with $P_z=3\mathrm{GeV}$, they cannot provide information about this amplitude’s end point behavior. On the valence-quark domain, similar outcomes characterize PqDFs. In this connection, however, the ratio of kaon-to-pion $u$-quark PqDFs is found to provide a good approximation to the true parton distribution function ratio on $0.4\lesssim x\lesssim 0.8$, suggesting that with existing resources computations of ratios of parton quasidistributions can yield results that support empirical comparison.

• Received 26 February 2018

DOI:https://doi.org/10.1103/PhysRevD.97.094014