The combination of galaxy–galaxy lensing (GGL) and galaxy clustering is a powerful probe of lowredshift matter clustering, especially if it is extended to the nonlinear regime. To this end, we use an Nbody and halo occupation distribution (HOD) emulator method to model the redMaGiC sample of colourselected passive galaxies in the Dark Energy Survey (DES), adding parameters that describe central galaxy incompleteness, galaxy assembly bias, and a scaleindependent multiplicative lensing bias Alens. We use this emulator to forecast cosmological constraints attainable from the GGL surface density profile ΔΣ(rp) and the projected galaxy correlation function wp, gg(rp) in the final (Year 6) DES data set over scales $r_p=0.3\!\!30.0\, h^{1} \, \mathrm{Mpc}$. For a $3{{\ \rm per\ cent}}$ prior on Alens we forecast precisions of $1.9{{\ \rm per\ cent}}$, $2.0{{\ \rm per\ cent}}$, and $1.9{{\ \rm per\ cent}}$ on Ωm, σ8, and $S_8 \equiv \sigma _8\Omega _m^{0.5}$, marginalized over all halo occupation distribution (HOD) parameters as well as Alens. Adding scales $r_p=0.3\!\!3.0\, h^{1} \, \mathrm{Mpc}$ improves the S8 precision by a factor of ∼1.6 relative to a large scale ($3.0\!\!30.0\, h^{1} \, \mathrm{Mpc}$) analysis, equivalent to increasing the survey area by a factor of ∼2.6. Sharpening the Alens prior to $1{{\more »
This content will become publicly available on December 10, 2022
 Authors:
 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
 Award ID(s):
 2009210
 Publication Date:
 NSFPAR ID:
 10349846
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Volume:
 509
 Issue:
 4
 Page Range or eLocationID:
 4982 to 4996
 ISSN:
 00358711
 Sponsoring Org:
 National Science Foundation
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