There should be an imprint of the kinematic dipole observed in the cosmic microwave background in any cosmological tracer: The dipole is set by the Solar System barycentric velocity relative to the local Hubble flow, and that same velocity should imprint a dipole on anything cosmological. I have been working on this in part because it is a good measurement to make with Quaia, and in part because the dipole in the quasars is controversial. I have many thoughts, but I will save them for later.
Anyways, Abby Williams (NYU) has been working on making this measurement, and her dipole amplitude and direction depend on what we hold fixed and what we vary (in particular selection-function components), and they also depend on what sky region we use. None of this is surprising; the selection function has a strong dipole in it, and it is not known precisely. But then I don't understand how the studies published previously have such good error bars. Maybe they didn't consider the various different fitting regimes?
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