The curve, given in polar coordinates as $r(\theta)=\sin(\theta)/\theta$ is plotted below.

This is similar to the classical cardioid, but it is not the same curve (the curve above is not even algebraic, I believe). Does this curve have a name? Does it show up somewhere? This curve has the property that it solves $\mathrm{Im}(1/z+\log(z))=0$, if this perhaps rings a bell.

This particular curve arises in some research I am working on at the moment, and it would be great if it perhaps connects to some classical area.

**Edit:** Thanks for the great references!
As a reward, here is a more artistic rendering of the shape
using a type of complex dynamical systems.