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arXiv · 2501.16122

BrahMap: A scalable and modular map-making framework for the CMB experiments

Avinash Anand·Giuseppe Puglisi
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Abstract

The cosmic microwave background (CMB) experiments have reached an era of unprecedented precision and complexity. Aiming to detect the primordial B-mode polarization signal, these experiments will soon be equipped with $10^{4}$ to $10^{5}$ detectors. Consequently, future CMB missions will face the substantial challenge of efficiently processing vast amounts of raw data to produce the initial scientific outputs - the sky maps - within a reasonable time frame and with available computational resources. To address this, we introduce BrahMap, a new map-making framework that will be scalable across both CPU and GPU platforms. Implemented in C++ with a user-friendly Python interface for handling sparse linear systems, BrahMap employs advanced numerical analysis and high-performance computing techniques to maximize the use of super-computing infrastructure. This work features an overview of the BrahMap's capabilities and preliminary performance scaling results, with application to a generic CMB polarization experiment.

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Avinash Anand, Giuseppe Puglisi. 2025-01-27. BrahMap: A scalable and modular map-making framework for the CMB experiments. https://doi.org/10.1109/pdp66500.2025.00060

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