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Localizing Transformations of the Galaxy-Galaxy Lensing Observable.
Youngsoo Park1, Eduardo Rozo2, Elisabeth Krause3
1Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS, The University of Tokyo, Kashiwa, Chiba 277-8583, Japan.
Physical Review Letters
|January 29, 2021
Summary
Galaxy-galaxy lensing analyses are improved by a new method that removes theoretical nonlocality. This technique enhances cosmological signal extraction and expands usable scales for galaxy lensing studies.
Area of Science:
- Cosmology
- Astrophysics
- Gravitational Lensing
Background:
- Galaxy-galaxy lensing analyses are affected by theoretical systematic errors due to signal nonlocality.
- Uncertainties in small-scale nonlinear modeling propagate to larger scales, limiting data analysis.
Purpose of the Study:
- To develop a method to remove nonlocality in galaxy-galaxy lensing signals.
- To enable the use of a wider range of scales in cosmological analyses.
Main Methods:
- Constructed a linear transformation of the standard galaxy-galaxy observable.
- The transformation removes nonlocality, isolating the cosmological signal on well-understood scales.
Main Results:
- The new observable is robust against nonlocality.
- This method allows for a significant extension of usable scales in galaxy-galaxy lensing.
Conclusions:
- The developed observable enhances the reliability and information content of galaxy-galaxy lensing data.
- This approach offers a more effective way to probe cosmological parameters using galaxy lensing.
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