DESI DR2 and ACT DR6 data yield 17σ LRG-velocity, 8.3σ ELG-velocity, and 6.8σ QSO-velocity detections plus a 3.1σ velocity-velocity signal, producing f_NL^loc = 15.9_{-34.4}^{+34.6} from the velocity field.
Bispectrum constraints on Primordial non-Gaussianities with the eBOSS DR16 quasars
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present constraints on $f_{\rm NL}$, the parameter quantifying the amplitude of local Primordial Non-Gaussianities (PNG), from a combined analysis of the tree-level power spectrum and bispectrum of Data Release $16$ (DR16) of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) quasar sample. In our analysis, we use the power spectrum measured with the optimal redshift weights that maximize the local PNG information together with the bispectrum estimated with the standard Feldman-Kaiser-Peacock weights. In the modeling, we incorporate the global and radial integral constraint corrections both in the power spectrum and in the bispectrum, for which we observe that only the radial integral constraint correction has a significant impact. Our constraints read $-6 < f_{\rm NL} < 20$ at $68\%$ confidence level and improve by $\sim 16\%$ over the previous power spectrum analysis of the same dataset. We observe the same improvement over the power spectrum analysis when the quasar response to PNG is lower. In this case, we find $-23 < f_{\rm NL} < 14$ at $68\%$ confidence level. Our findings are consistent with the Fisher matrix expectations.
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Joint power spectrum and bispectrum analysis from future HI intensity mapping surveys improves constraints on primordial feature amplitudes by 30-40% and achieves percent-level precision on oscillation frequencies when combined with CMB measurements.
Reports f_NL = -20.5^{+19.0}_{-18.1} (68% CL) from combined Quaia quasar auto-correlation and CMB lensing cross-correlation assuming p_phi=1, or -28.7^{+26.1}_{-24.6} for p_phi=1.6.
Updated SKAO-AA4 forecasts show multi-tracer HI+galaxy analyses can reach σ(f_local_NL)≲1 and improve αs bounds by tens of percent when combined with future CMB, while foregrounds and GR light-cone effects remain the main systematics.
citing papers explorer
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Measurement of the galaxy-velocity power spectrum of DESI tracers with the kinematic Sunyaev-Zeldovich effect using DESI DR2 and ACT DR6
DESI DR2 and ACT DR6 data yield 17σ LRG-velocity, 8.3σ ELG-velocity, and 6.8σ QSO-velocity detections plus a 3.1σ velocity-velocity signal, producing f_NL^loc = 15.9_{-34.4}^{+34.6} from the velocity field.
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Searching for primordial features with radio surveys: synergy between the power spectrum and bispectrum
Joint power spectrum and bispectrum analysis from future HI intensity mapping surveys improves constraints on primordial feature amplitudes by 30-40% and achieves percent-level precision on oscillation frequencies when combined with CMB measurements.
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Constraints on primordial non-Gaussianity from Quaia
Reports f_NL = -20.5^{+19.0}_{-18.1} (68% CL) from combined Quaia quasar auto-correlation and CMB lensing cross-correlation assuming p_phi=1, or -28.7^{+26.1}_{-24.6} for p_phi=1.6.
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Beyond {\Lambda}CDM with the SKA Observatory -- II: Unveiling the Secrets of the Early Universe
Updated SKAO-AA4 forecasts show multi-tracer HI+galaxy analyses can reach σ(f_local_NL)≲1 and improve αs bounds by tens of percent when combined with future CMB, while foregrounds and GR light-cone effects remain the main systematics.