Speaker
Description
We present a search for gamma-ray emission from the Sun using data collected between 2021 and 2025 with the Water Cherenkov Detector Array (WCDA) of the Large High Altitude Air-shower Observatory (LHAASO). We apply an equal-zenith-angle background method and perform a spatial and spectral likelihood analysis using the WCDA detector response and point-spread function. For the cumulative bin0--6 sample, the best-fit point source is located at $(\Delta\mathrm{RA},\Delta\mathrm{Dec})=(0.10\pm0.17,\,-0.05\pm0.23)^\circ$, consistent with the solar position. The fitted spectrum has a power-law index of $\Gamma=3.22\pm0.15$ and a differential flux normalization of $\phi_0=5.03^{+2.26}_{-1.55}\times10^{-16}\,\mathrm{TeV^{-1}\,cm^{-2}\,s^{-1}}$. The corresponding local test statistic is $\mathrm{TS}=42.6$, equivalent to a local significance of approximately $6.5\sigma$. The likelihood-based significance distributions show a residual positive bias, which is being further investigated. These preliminary results indicate an excess spatially consistent with the solar position.