# Weighing neutrinos with the halo environment

## TL;DR

This paper shows how the environment around halos can significantly enhance the detection of neutrino mass signatures in large-scale structure, leveraging galaxy surveys.

## Contribution

It introduces a novel method to amplify the scale-dependent bias signal of neutrinos by using halo environment information from galaxy clustering and lensing.

## Key findings

- Environment-based signal enhancement improves neutrino mass detection.
- Method leverages measurable galaxy survey data.
- First demonstration of environment's role in neutrino mass inference.

## Abstract

Nonlinear objects like halos and voids exhibit a scale-dependent bias on linear scales in massive neutrino cosmologies. The shape of this scale-dependent bias is a unique signature of the neutrino masses, but the amplitude of the signal is generally small, of the order of $f_\nu$, the contribution of neutrinos to the total matter content ($\lesssim 1\%$). In this paper, we demonstrate for the first time how the strength of this signal can be substantially enhanced by using information about the halo environment at a range of scales. This enhancement is achieved by using certain combinations of the large scale Cold Dark Matter and total matter environments of halos, both of which are measurable from galaxy clustering and weak lensing surveys.