Comparison of weak lensing by NFW and Einasto halos and systematic errors
- Dipartimento di Fisica e Astronomia, Alma Mater Studiorum – Università di Bologna, viale Berti Pichat 6/2, 40127 Bologna (Italy)
- INAF, Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna (Italy)
Recent N-body simulations have shown that Einasto radial profiles provide the most accurate description of dark matter halos. Predictions based on the traditional NFW functional form may fail to describe the structural properties of cosmic objects at the percent level required by precision cosmology. We computed the systematic errors expected for weak lensing analyses of clusters of galaxies if one wrongly models the lens density profile. Even though the NFW fits of observed tangential shear profiles can be excellent, viral masses and concentrations of very massive halos (∼> 10{sup 15}M{sub ⊙}/h) can be over- and underestimated by 0∼ 1 per cent, respectively. Misfitting effects also steepen the observed mass-concentration relation, as observed in multi-wavelength observations of galaxy groups and clusters. Based on shear analyses, Einasto and NFW halos can be set apart either with deep observations of exceptionally massive structures (∼> 2×10{sup 15}M{sub ⊙}/h) or by stacking the shear profiles of thousands of group-sized lenses (∼> 10{sup 14}M{sub ⊙}/h)
- OSTI ID:
- 22525049
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2016, Issue 01; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
Similar Records
CLASH: Weak-lensing shear-and-magnification analysis of 20 galaxy clusters
CLASH: JOINT ANALYSIS OF STRONG-LENSING, WEAK-LENSING SHEAR, AND MAGNIFICATION DATA FOR 20 GALAXY CLUSTERS