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Title: An analytic surface density profile for ΛCDM haloes and gravitational lensing studies
ABSTRACT

We introduce an analytic surface density profile for dark matter haloes that accurately reproduces the structure of simulated haloes of mass Mvir = 107–1011 M⊙, making it useful for modelling line-of-sight (LOS) perturbers in strong gravitational lensing models. The two-parameter function has an analytic deflection potential and is more accurate than the projected Navarro, Frenk, and White profile commonly adopted at this mass scale for perturbers, especially at the small radii of most relevant for lensing perturbations. Using a characteristic radius, R−1, where the log slope of surface density is equal to −1, and an associated surface density, Σ−1, we can represent the expected lensing signal from LOS haloes statistically, for an ensemble of halo orientations, using a distribution of projected concentration parameters, $\mathcal {C}_{\rm vir} := r_{\rm vir}/ R_{-1}$. Though an individual halo can have a projected concentration that varies with orientation with respect to the observer, the range of projected concentrations correlates with the usual three-dimensional halo concentration in a way that enables ease of use.

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Award ID(s):
1910965
NSF-PAR ID:
10486286
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
528
Issue:
1
ISSN:
0035-8711
Format(s):
Medium: X Size: p. 444-458
Size(s):
["p. 444-458"]
Sponsoring Org:
National Science Foundation
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