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We present the first results of a high-cadence Swift monitoring campaign($3-4$ visits per day for $75$ days) of the Seyfert 1.5 galaxy NGC 6814characterizing its variability throughout the X-ray and UV/optical wavebands.Structure function analysis reveals an X-ray power law($\alpha=0.5^{+0.2}_{-0.1}$) that is significantly flatter than the onemeasured in the UV/optical bands ($\langle\alpha\rangle\approx1.5$), suggestingdifferent physical mechanisms driving the observed variability in each emissionregion. The structure function break-time is consistent across the UV/opticalbands ($\langle\tau\rangle\approx2.3~\mathrm{d}$), suggesting a very compactemission region in the disc. Correlated short time-scale variability measuredthrough cross-correlation analysis finds a lag-wavelength spectrum that isinconsistent with a standard disc reprocessing scenario($\tau\propto\lambda^{4/3}$) due to significant flattening in the opticalwavebands. Flux-flux analysis finds an extremely blue AGN spectral component($F_{\nu}\propto\lambda^{-0.85}$) that does not follow a standard accretiondisc profile ($F_{\nu}\propto\lambda^{-1/3}$). While extreme outer disctruncation ($R_{\mathrm{out}}=202\pm5~r_g$) at a standard accretion rate($\dot{m}_{\mathrm{Edd}}=0.0255\pm0.0006$) may explain the shape of the AGNspectral component, the lag-wavelength spectrum requires more modest truncation($R_{\mathrm{out}}=1,382^{+398}_{-404}~r_g$) at an extreme accretion rate($\dot{m}_{\mathrm{Edd}}=1.3^{+2.1}_{-0.9}$). No combination of parameters cansimultaneously explain both results in a self-consistent way. Our results offerthe first evidence of a non-standard accretion disc in NGC 6814.

Characterizing X-ray, UV, and optical variability in NGC 6814 using high-cadence Swift observations from a 2022 monitoring campaign