Phenomenological power spectrum models for H$\alpha$ emission line galaxies from the Nancy Grace Roman Space Telescope

Abstract

The High Latitude Spectroscopic Survey (HLSS) is the reference baseline spectroscopic survey for NASA's Nancy Grace Roman space telescope, measuring redshifts of $\sim 10$M H$\alpha$ emission line galaxies over a $2000$ deg${}^2$ footprint at $z=1-2$. In this work, we use a realistic Roman galaxy mock catalogue to explore optimal phenomenological modeling of the measured power spectrum. We consider two methods for modeling the redshift-space distortions (Kaiser squashing and another with a window function on $\beta$ that selects out the coherent radial infall pairwise velocities, $M_A$ and $M_B$, respectively), two models for the nonlinear impact of baryons that smears the BAO signal (a fixed ratio between the smearing scales in the perpendicular and parallel dimensions and another where these smearing scales are kept as a free parameters, P${}_{dw}(k|k_{\ast })$ and P${}_{dw}(k|{\Sigma }_{\perp },{\Sigma }_{\parallel })$, respectively), and two analytical emulations of nonlinear growth (one employing the halo model and another formulated from simulated galaxy clustering of a semi-analytical model, $F_{HM}$ and $F_{SAM}$, respectively). We find that the best model combination employing $F_{HM}$ is $P_{dw}(k|k_{\ast })\ast F_{HM}\ast M_B$, while the best combination employing $F_{SAM}$ is $P_{dw}(k|k_{\ast })\ast F_{SAM}\ast M_B$, which leads to unbiased measurements of cosmological parameters. We compare these to the Effective Field Theory of Large-Scale Structure perturbation theory model $P_{EFT}(k|\Theta )$, and find that our simple phenomenological models are comparable across the entire redshift range for $k_{max}=0.25$ and $0.3$ $h$/Mpc. We expect the tools that we have developed to be useful in probing dark energy and testing gravity using Roman in an accurate and robust manner.

17 pages, 3 figures, 4 tables, Accepted to MNRAS 23 May 2023

References in corpus (22)

• The NumPy array: a structure for efficient numerical computation
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• Why your model parameter confidences might be too optimistic -- unbiased estimation of the inverse covariance matrix
• A test of the nature of cosmic acceleration using galaxy redshift distortions
• The Effective Field Theory of Cosmological Large Scale Structures
• On the Robustness of the Acoustic Scale in the Low-Redshift Clustering of Matter
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Anisotropic galaxy clustering in Fourier-space
• Testing cosmological structure formation using redshift-space distortions
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in Fourier-space
• The IR-resummed Effective Field Theory of Large Scale Structures
• A 2.5% measurement of the growth rate from small-scale redshift space clustering of SDSS-III CMASS galaxies
• The detectability of baryonic acoustic oscillations in future galaxy surveys
• Figure of Merit for Dark Energy Constraints from Current Observational Data
• The High Latitude Spectroscopic Survey on the Nancy Grace Roman Space Telescope
• Differentiating dark energy and modified gravity with galaxy redshift surveys
• Cosmology with the EFTofLSS and BOSS: dark energy constraints and a note on priors
• Stringent ${\sigma }_8$ constraints from small-scale galaxy clustering using a hybrid MCMC+emulator framework
• Testing one-loop galaxy bias: joint analysis of power spectrum and bispectrum
• The Aemulus Project V: Cosmological constraint from small-scale clustering of BOSS galaxies
• What is the best way to measure baryonic acoustic oscillations?
• Predicting Hα emission line galaxy counts for future galaxy redshift surveys
• Creating Jackknife and Bootstrap estimates of the covariance matrix for the two-point correlation function

Cited by in corpus (1)

• Radio-optical synergies at high redshift to constrain primordial non-Gaussianity