Mapping the baryons with kSZ-cosmic shear cross-correlations by Anoma Ganguly

Value of the Information & Strength of the Argument

The talk presents a valuable contribution by introducing an estimator that directly probes the electron-matter power spectrum, circumventing the often uncertain modeling of galaxy-halo connections. The argumentation is logical and well-supported with quantitative forecasts. The speaker systematically compares with existing estimators, highlighting the advantages of the new approach, such as reduced reliance on halo occupation models and intrinsic insensitivity to CMB foregrounds. The inclusion of nulling to localize redshift contributions demonstrates careful methodological development. The forecasts are based on realistic survey specifications and provide clear detection expectations, enhancing the credibility of the proposed technique.

Scientific Rigor, Source Quality, Title Accuracy

The talk is rigorous, with a clear theoretical framework and quantitative predictions. The speaker cites a recent paper on arXiv (though the link is not provided) and refers to ongoing and planned surveys. The title accurately captures the essence of the work. The methodology is grounded in established cosmological principles, and the limitations and noise sources are acknowledged. The presentation includes a Q&A session where clarifications are provided, further demonstrating the solidity of the work. Overall, the scientific rigor is high, and the title is appropriate.

The title precisely reflects the content: the talk presents a method using kSZ-cosmic shear cross-correlations to map baryonic gas distribution.

8/10

Scientific talk presented at a reputable institution (ICTS) with clear methodology, technical depth, and reference to a recent arXiv paper. The content is well-structured and based on established cosmological observation frameworks.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 00:30Introduction to weak lensing surveys and the challenge of modeling baryons.
• 03:00Explanation of kSZ effect and why standard cross-correlation with shear is zero.
• 06:00Presentation of the estimator: constructing a kSZ template from convergence and velocity.
• 09:00Comparison with other kSZ estimators (GGT and TTG types).
• 13:00Nulling technique to localize lensing kernels for better redshift resolution.
• 16:00Forecasts for signal-to-noise ratio with various surveys and precision on matter power spectrum.
• 19:00Discussion of noise sources: shape noise and velocity reconstruction noise.
• 21:00Summary and conclusions, with reference to a recent arXiv paper.

• The Concurrence of Mega-Surveys Workshop Program — Workshop where this talk was presented