Cross-correlation results of HAT-P-70b with robust detections that have S/N ≥ 4 (top: Ca II, bottom: Fe I). Left panel: cross-correlation residual map. The horizontal white dashed lines mark the first and fourth contacts of the transit event. The orange tilted dashed line represents the planet's trajectory. Middle panel: The cross-correlation S/N as a function of the velocity shift (Δv) and planet Keplerian velocity (K_p). The vertical and horizontal white dashed lines show the expected location of the planet signal (0 km s⁻¹ and 187 km s⁻¹). The black, red, and blue contour lines mark the region with S/N equal to 3, 4, and 5. Right panel: The 1D cross-correlation function at the best K_p (black) along with the best-fit Gaussian profile (red). The green line is the same result, but based on the K_p in the literature (see Section 3.3.3 for details). The gray shaded region highlights the cross-correlation S/N between −3 and 3.