Beschreibung
Scale-dependent bias, a result of nonlinear modulation of small-scale statistics by long-wavelength modes, is a tell-tale sign of inflationary physics. Through the squeezed-limit bispectrum, the nonlinear coupling depends on both the magnitude ratio and the relative angle between the long and short modes, the latter largely disregarded as inaccessible through two-point correlations of the density field. Although this is true for complete tracer samples, it is not true when selection effects are prominent. In this talk, I will demonstrate through separate-universe simulations, a scale-dependent bias from this angle-dependent modulation can be recovered in the halo clustering power spectrum by curating subsamples selected via non-scalar properties. The same effect can also be seen in the 3D flux power spectra of the Lyman-alpha forest. This signal is orthogonal to the isotropic local shape when considering tracer-matter cross-correlations, and opens up a new window into primordial non-Gaussianity searches.