2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179317We find the following improved laboratory bounds on the coupling of light pseudoscalars to protons and neutrons: $g_p^2/4π< 1.7 \times 10^{-9}$ and $g_n^2/4π< 6.8 \times 10^{-8}$. The limit on $g_p$ arises since a nonzero $g_p$ would induce a coupling of the pseudoscalar to two photons, which is limited by experiments studying laser beam propagation in magnetic fields. Combining our bound on $g_p$ with a recent analysis of Fischbach and Krause on two-pseudoscalar exchange potentials and experiments testing the equivalence principle, we obtain our limit on $g_n$. (PACS number(s): 14.20.Dh/14.80.-j/12.20.Fv/04.90.+e)5 pages, 1 figure, to be published in Phys. Rev. D., corrected some typosHigh Energy Physics - Phenomenologytext