Cartoon illustrating the impact geometry of multiple sightlines intercepting conical outflows. The plane of sky is marked by the x′-y′ axes and the z′ axis points to distant objects. The outflow is represented by the cone oriented along the rotation axis |$\hat{z}$| with inclination angle i0 and opening angle 2 × θ0. It is expected from this orientation that when θ0 is sufficiently large to cross the plane of the sky, the outflows would imprint blueshifted absorption features in the spectra of background sources. A lack of blueshifted components would therefore constrain the maximum θ0. Within the cone, gas streams move outward at different angle θ′ ≲ θ0 from |$\hat{z}$| with corresponding inclination angle i′ (the thick paint brush line is marked as an example of such outward moving stream). In principle, the velocity gradient along the streams can be directly constrained by the average velocity shears observed between different sightlines (marked A and B) that occur at the same azimuthal angle on the sky (equation 4).
