Constraints on Primordial Oscillatory Features from the Power Spectrum and Bispectrum of Redshift-Space Galaxy Clustering in DESI DR1
Abstract
We constrain oscillatory features in the primordial power spectrum using the public DESI DR1 galaxy and quasar clustering data. Our analysis is based on a custom pipeline for the redshift-space power spectrum and bispectrum of the six main DESI DR1 tracers, modeled with the Lagrangian effective field theory,which provides a principled resummation of the non-linear damping of the features. We consider oscillations that are linear and logarithmic in wavenumber, and, for the first time, consistently include the galaxy bispectrum in the search. We also study the dependence of the results on the background cosmology, which is important given the tension between the DESI BAO and \textit{Planck} data within the baseline cosmological model. Marginalizing over ΛCDM parameters, we bound the amplitude of linear and logarithmic oscillations to Alin<0.033 and Alog<0.035 respectively (at 95%CL) across the frequency ranges ωlinphys∈(20,800) Mpc and ωlog∈(2.5,80). The constraints reach percent-level precision away from the frequencies degenerate with the baryon acoustic oscillations (BAO). Fixing to the \textit{Planck} 2018 cosmology, the bounds tighten to Alin<0.024 and Alog<0.031, but in this case we also find a ≃ 3σ global preference for a logarithmic feature with ωlog≃ 15, dominated by the LRG2 sample, whose local wavelength matches the apparent BAO scale at wavenumbers best constrained by DESI. Since the preference for this feature disappears once the cosmological parameters are varied, we expect that it is a manifestation of the known distance-scale tension between the DESI and \textit{Planck} data rather than a primordial signal. Our analysis thus emphasizes the importance of cosmology marginalization in searches for primordial features.
Related
- Wedge-avoidance Fisher Forecasts for Primordial Features from Dark-Ages 21-cm Power Spectrum and Bispectrum
- Cross-Bispectrum Constraints from HI Intensity Mapping and Galaxy Surveys
- Cosmological constraints from the DESI DR1 Bispectrum Full-Shape and DR2 BAO
- Small-Scale Clustering of Primordial Black Holes: The Little Red Dot Mass Function and the High-Redshift Galaxy Tension
- Initial clustering of primordial black holes: A general formulation for arbitrary local non-Gaussianity
BibTeX
@misc{chen2026constraints,
title = {{Constraints on Primordial Oscillatory Features from the Power Spectrum and Bispectrum of Redshift-Space Galaxy Clustering in DESI DR1}},
author = {Shi-Fan Chen and Anton Chudaykin and Mikhail M. Ivanov and Oliver H. E. Philcox and Mario Ballardini},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.10530},
eprint = {2610.10530},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.10530},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Constraints on Primordial Oscillatory Features from the Power Spectrum and Bispectrum of Redshift-Space Galaxy Clustering in DESI DR1
AU - Shi-Fan Chen
AU - Anton Chudaykin
AU - Mikhail M. Ivanov
AU - Oliver H. E. Philcox
AU - Mario Ballardini
PY - 2026
DA - 2026/10/07
PB - arXiv
DO - 10.48550/arxiv.2610.10530
UR - https://arxiv.org/abs/2610.10530
AB - We constrain oscillatory features in the primordial power spectrum using the public DESI DR1 galaxy and quasar clustering data. Our analysis is based on a custom pipeline for the redshift-space power spectrum and bispectrum of the six main DESI DR1 tracers, modeled with the Lagrangian effective field theory,which provides a principled resummation of the non-linear damping of the features. We consider oscillations that are linear and logarithmic in wavenumber, and, for the first time, consistently include the galaxy bispectrum in the search. We also study the dependence of the results on the background cosmology, which is important given the tension between the DESI BAO and \textit{Planck} data within the baseline cosmological model. Marginalizing over ΛCDM parameters, we bound the amplitude of linear and logarithmic oscillations to A_lin<0.033 and A_log<0.035 respectively (at 95%CL) across the frequency ranges ω_lin^phys∈(20,800) Mpc and ω_log∈(2.5,80). The constraints reach percent-level precision away from the frequencies degenerate with the baryon acoustic oscillations (BAO). Fixing to the \textit{Planck} 2018 cosmology, the bounds tighten to A_lin<0.024 and A_log<0.031, but in this case we also find a ≃ 3σ global preference for a logarithmic feature with ω_log≃ 15, dominated by the LRG2 sample, whose local wavelength matches the apparent BAO scale at wavenumbers best constrained by DESI. Since the preference for this feature disappears once the cosmological parameters are varied, we expect that it is a manifestation of the known distance-scale tension between the DESI and \textit{Planck} data rather than a primordial signal. Our analysis thus emphasizes the importance of cosmology marginalization in searches for primordial features.
ER -