Searching for eV-mass axionlike particles with cross correlations between line intensity and weak lensing maps

We study cross correlations between line intensity and weak lensing maps to search for axion-like particles (ALPs). Radiative decay of eV-mass ALPs can contribute cosmic background emissions at optical infrared wavelengths. Line mapping is a unique means measuring the emission given photon frequency. If constitute abundance dark matter, correlate with large-scale structures probed by gravitational effects in galaxy imaging surveys. develop theoretical framework predict correlation. then explore potentiality probing correlation upcoming galaxy-imaging spectral Assuming SPHEREx Vera Rubin Observatory's Legacy Survey Space Time (LSST), we find that ALP be greater than astrophysical-line counterparts wavelength $\sim3000\, {\rm nm}$ particle mass $m_a\sim1\, \mathrm{eV}$ particle-to-two-photons coupling $g_{a\gamma\gamma}\sim1\times10^{-11}\, \mathrm{GeV}^{-1}$. also null detection place $2\sigma$-level upper bound $g_{a\gamma\gamma} \lower.5ex\hbox{$\; \buildrel < \over \sim \;$} 10^{-11}\, \mathrm{GeV}^{-1}$ ALPs, improving current constraint factor $\sim10$. make forecast expected constraints on parameters LSST Fisher analysis, providing guideline searching structure data.