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Blueshifts - or, more accurately, blue asymmetries - in broad emission linessuch as CIV $\lambda$1550 are common in luminous quasars and correlate withfundamental properties such as Eddington ratio and broad absorption line (BAL)characteristics. However, the formation of these blueshifts is still notunderstood, and neither is their physical connection to the BAL phenomenon oraccretion disc. In this work, we present Monte Carlo radiative transfer andphotoionization simulations using parametrized biconical disc-wind models. Wetake advantage of the azimuthal symmetry of a quasar and show that we canreproduce CIV blueshifts provided that (i) the disc-midplane is optically thickout to radii beyond the line formation region, so that the receding wind biconeis obscured; and (ii) the system is viewed from relatively low (that is, moreface-on) inclinations ($\lesssim40^\circ$). We show that CIV emission lineblueshifts and BALs can form in the same wind structure. The velocity profileof the wind has a significant impact on the location of the line formationregion and the resulting line profile, suggesting that the shape of theemission lines can be used as a probe of wind-driving physics. While we aresuccessful at producing blueshifts/blue asymmetries in outflows, we struggle tomatch the detailed shape or skew of the observed emission line profiles. Inaddition, our models produce redshifted emission-line asymmetries for certainviewing angles. We discuss our work in the context of the CIV $\lambda$1550emission blueshift versus equivalent-width space and explore the implicationsfor quasar disc wind physics.

A disc wind model for blueshifts in quasar broad emission lines