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Updated: Jul 31, 2026
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Joint cosmic microwave background and weak lensing analysis: constraints on cosmological parameters
Carlo R Contaldi1, Henk Hoekstra, Antony Lewis
1CITA, University of Toronto, 60 St. George Street, Toronto, M5S 3H8, Ontario, Canada. contaldi@cita.utoronto.ca
Physical Review Letters
|July 15, 2003
Summary
Cosmic Microwave Background (CMB) and weak lensing data provide powerful cosmological constraints. This combined analysis accurately determines key parameters like matter density and the Hubble constant.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- Cosmic Microwave Background (CMB) observations offer insights into the early universe.
- Weak gravitational lensing by galaxy clusters probes the distribution of matter.
- Combining these datasets leverages their complementary strengths for robust cosmological parameter estimation.
Purpose of the Study:
- To derive precise constraints on cosmological parameters.
- To test the concordance of current cosmological models.
- To explore the synergy between CMB and weak lensing data.
Main Methods:
- Combined analysis of CMB data and red-sequence cluster survey weak lensing results.
- Inclusion of Big Bang nucleosynthesis constraints.
- Statistical analysis to determine parameter values and uncertainties.
Main Results:
- Accurate determination of the amplitude of fluctuations, sigma(8) = 0.89 ± 0.05.
- Precise measurement of matter density, Omega(m) = 0.30 ± 0.03.
- Constrained Hubble parameter, H(0) = 70 ± 3 km s⁻¹ Mpc⁻¹, consistent with HST results.
Conclusions:
- The combination of CMB and weak lensing data provides powerful cosmological constraints.
- This approach yields highly accurate determinations of key cosmological parameters.
- The results support the current standard model of cosmology.
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