Cosmic Flows on 100 Mpc/h scales

TL;DR

This paper introduces a novel method for calculating bulk flow moments in galaxy motions, enabling the design of window functions with optimized peak sharpness and minimal external amplitude, improving large-scale flow analysis.

Contribution

The paper presents a new technique to design bulk flow moments with tailored window functions, enhancing the analysis of galactic motions on large scales.

Findings

Method allows for customized window functions for bulk flow moments.

Improves the accuracy of large-scale galactic motion measurements.

Addresses limitations of maximum likelihood estimate weights.

Abstract

To study galactic motions on the largest available scales, we require bulk flow moments whose window functions have as narrow a peak as possible and having as small an amplitude as possible outside the peak. Typically the moments found using the maximum likelihood estimate weights do not meet these criteria. We present a new method for calculating weights for moments that essentially allow us to "design" the moment's window function, subject, of course, to the distribution and uncertainties of the available data.