J-PAS: Forecasting constraints on Neutrino Masses

TL;DR

This work presents a Fisher-matrix forecast for J-PAS's ability to constrain the sum of neutrino masses using galaxy clustering data, employing the FARO multi-tracer framework and exploring non-linear scales, tracer types, and sky coverage. By combining J-PAS with Planck CMB data and Pantheon Plus SN data, the authors quantify how the upper bound on Σm_ν improves from a few tenths of an eV to the sub-0.1 eV level in the ΛCDM+Σm_ν model and to ~0.12 eV in a w_0w_a CDM+Σm_ν framework, depending on the dataset. The results highlight the critical role of non-linear information, survey area, and tracer choice (ELGs vs LRGs) and show that J-PAS can provide competitive constraints comparable to other Stage IV surveys, potentially informing neutrino mass ordering and tensions with terrestrial measurements. The study also emphasizes that including weak-lensing information in the future could further tighten constraints, underscoring J-PAS as a valuable cross-check for forthcoming large-scale structure analyses.

Abstract

The large-scale structure survey J-PAS is taking data since October 2023. In this work, we present a forecast based on the Fisher matrix method to establish its sensitivity to the sum of the neutrino masses. We adapt the Fisher Galaxy Survey Code (FARO) to account for the neutrino mass under various configurations applied to galaxy clustering measurements. This approach allows us to test the sensitivity of J-PAS to the neutrino mass across different tracers, with and without non-linear corrections, and under varying sky coverage. We perform our forecast for two cosmological models: $ΛCDM + \sum m_ν$ and $w_0w_a CDM + \sum m_ν$. We combine our J-PAS forecast with Cosmic Microwave Background (CMB) data from the Planck Collaboration and Type Ia supernova (SN) data from Pantheon Plus. Our analysis shows that, for a sky coverage of 8,500 square degrees, J-PAS galaxy clustering data alone will constrain the sum of the neutrino masses to an upper limit at 95% C.L of $\sum m_ν< 0.32$ eV for the $ΛCDM + \sum m_ν$ model, and $\sum m_ν< 0.36$ eV for the $w_0w_a CDM + \sum m_ν$ model. When combined with Planck data, the upper limit improves significantly. For J-PAS+Planck at 95% C.L, we find $\sum m_ν< 0.061$ eV for the $ΛCDM + \sum m_ν$ model, and for J-PAS+Planck+Pantheon Plus, we obtain $\sum m_ν< 0.12$ eV for the $w_0w_a CDM + \sum m_ν$ model. These results demonstrate that J-PAS clustering measurements can play a crucial role in addressing challenges in the neutrino sector, including potential tensions between cosmological and terrestrial measurements of the neutrino mass, as well as in determining the mass ordering.

Figures (9)

• Figure 1: Galaxy number density in units of $\:h^3 \: \text{Mpc}^{-3}$ and redshift errors for each divided sub-sample and each tracer as a function of redshift.
• Figure 2: Confidence contours at $68\%$ and $95\%$ C.L. for the full survey with $f_{\text{sky}} = 8500 \:\text{deg}^2$ comparing an Optimistic case with $k_{\text{max}}(\text{GCs}) = 0.20 \, h \, \text{Mpc}^{-1}$ , and a Pessimistic case with $k_{\text{max}}(\text{GCs}) = 0.10 \, h \, \text{Mpc}^{-1}$, both with non-linear corrections.
• Figure 3: Confidence contours at $68\%$ and $95\%$ C.L. for the full survey with $f_{\text{sky}} = 8500 \:\text{deg}^2$ in an Optimistic case with $k_{\text{max}}(\text{GCs}) = 0.20 \, h \, \text{Mpc}^{-1}$, comparing an analysis assuming linear theory to the analysis including non-linear corrections.
• Figure 4: Confidence contours at $68\%$ and $95\%$ C.L. comparing a partial survey with $f_{\text{sky}} = 1500 \:\text{deg}^2$ and a full survey with $f_{\text{sky}} = 8500 \:\text{deg}^2$, both for an Optimistic case with $k_{\text{max}}(\text{GCs}) = 0.20 \, h \, \text{Mpc}^{-1}$, and including non-linear corrections.
• Figure 5: Confidence contours at $68\%$ and $95\%$ C.L. for the full survey with $f_{\text{sky}} = 8500 \:\text{deg}^2$ in an Optimistic case with $k_{\text{max}}(\text{GCs}) = 0.20 \, h \, \text{Mpc}^{-1}$, comparing the cosmological constraints from the LRG and ELG samples, and both samples combined.