On the effect of the ionising background on the Lyα forest autocorrelation function

Abstract

An analytical framework is presented to understand the effects of a fluctuating intensity of the cosmic ionising background on the correlations of the Lyα forest transmission fraction measured in quasar spectra. In the absence of intensity fluctuations, the Lyα power spectrum should have the expected cold dark matter power spectrum with redshift distortions in the linear regime, with a bias factor b_δ and a redshift distortion parameter β that depend on redshift but are independent of scale. The intensity fluctuations introduce a scale dependence in both b_δ and β, but keeping their product b_δβ fixed. Observations of the Lyα correlations and cross-correlations with radiation sources like those being done at present in the BOSS survey of SDSS-III (Busca et al. 2013; Slosar et al. 2013; Font-Ribera et al. 2014) have the potential to measure this scale dependence, which reflects the biasing properties of the sources and absorbers of the ionising background. We also compute a second term affecting the Lyα spectrum, due to shot noise in the sources of radiation. This term is very large if luminous quasars are assumed to produce the ionising background and to emit isotropically with a constant luminosity, but should be reduced by a contribution from galaxies, and by the finite lifetime and anisotropic emission of quasars.

12 pages, 6 figures Accepted for publication in MNRAS

References in corpus (7)

• Baryon Acoustic Oscillations in the Lyα forest of BOSS DR11 quasars
• Baryon Acoustic Oscillations in the Ly-α forest of BOSS quasars
• Quasar-Lyman $\alpha$ Forest Cross-Correlation from BOSS DR11 : Baryon Acoustic Oscillations
• HeII Reionization and its Effect on the IGM
• The End of Helium Reionization at z~2.7 Inferred from Cosmic Variance in HST/COS HeII Lyman Alpha Absorption Spectra
• Scale-dependent bias in the BAO-scale intergalactic neutral hydrogen
• The Acoustic Peak in the Lyman Alpha Forest

Cited by in corpus (52)

• Large-Scale Galaxy Bias
• Cosmological implications of baryon acoustic oscillation (BAO) measurements
• Measurement of BAO correlations at $z=2.3$ with SDSS DR12 \lya-Forests
• The Evolution of the Intergalactic Medium
• Neutrino masses and cosmology with Lyman-alpha forest power spectrum
• Baryon acoustic oscillations from the complete SDSS-III Ly$\alpha$-quasar cross-correlation function at $z=2.4$
• DESI 2024 IV: Baryon Acoustic Oscillations from the Lyman Alpha Forest
• Baryon acoustic oscillations from the cross-correlation of Ly$\alpha$ absorption and quasars in eBOSS DR14
• Baryon acoustic oscillations at z = 2.34 from the correlations of Ly$\alpha$ absorption in eBOSS DR14
• Lyman-alpha Forests cool Warm Dark Matter
• Constraints from Ly-$\alpha$ forests on non-thermal dark matter including resonantly-produced sterile neutrinos
• Large fluctuations in the hydrogen-ionizing background and mean free path following the epoch of reionization
• Early and Extended Helium Reionization Over More Than 600 Million Years of Cosmic Time
• Self-Consistent Modeling of Reionization in Cosmological Hydrodynamical Simulations
• The Non-Linear Power Spectrum of the Lyman Alpha Forest
• Protocluster Discovery in Tomographic Ly$\alpha$ Forest Flux Maps
• Constraining Reionization with the $z\sim 5-6$ Lyman-$\alpha$ Forest Power Spectrum: the Outlook after Planck
• Biased Tracers of Two Fluids in the Lagrangian Picture
• Constraints on the cosmic expansion rate at redshift 2.3 from the Lyman-$\alpha$ forest
• Intensity mapping with neutral hydrogen and the Hidden Valley simulations
• Modeling the Lyman-alpha Forest in Collisionless Simulations
• Redshift-space streaming velocity effects on the Lyman-$\alpha$ forest baryon acoustic oscillation scale
• Relativistic effects in Lyman-alpha forest
• PRIYA: A New Suite of Lyman-alpha Forest Simulations for Cosmology
• Broadband distortion modeling in Lyman-$\alpha$ forest BAO fitting
• Towards physics responsible for large-scale Lyman-$\alpha$ forest bias parameters
• The Ly$\alpha$ forest flux correlation function: a perturbation theory perspective
• Impact of inhomogeneous reionization on the Lyman-α forest
• The triply-ionized carbon forest from eBOSS: cosmological correlations with quasars in SDSS-IV DR14
• A new model framework for circumgalactic Ly$\alpha$ radiative transfer constrained by galaxy-Ly$\alpha$ forest clustering
• The Alcock-Paczyński effect from Lyman-$\alpha$ forest correlations: Analysis validation with synthetic data
• A neural network emulator for the Lyman-$\alpha$ 1D flux power spectrum
• Time-dependent fluctuations in the metagalactic photoionization background
• UV Background Fluctuations and Three-Point Correlations in the Large Scale Clustering of the Lyman-alpha Forest
• The impact of relativistic effects on the 3D Quasar-Lyman-$\alpha$ cross-correlation
• Direct cosmological inference from three-dimensional correlations of the Lyman-$\alpha$ forest
• On the accuracy of common moment-based radiative transfer methods for simulating reionization
• Estimates for the impact of Ultraviolet Background fluctuations on galaxy clustering measurements
• A new scale in the bias expansion
• The impact of temperature fluctuations on the large-scale clustering of the Ly$\alpha$ forest
• Forecasting constraints on the mean free path of ionizing photons at $z\ge 5.4$ from the Lyman-$\alpha$ forest flux auto-correlation function
• Large-scale fluctuations in the cosmic ionising background: the impact of beamed source emission
• Modeling Lyman-α Forest Cross-Correlations with LyMAS
• Boosting Line Intensity Map Signal-to-Noise with the Ly-$\alpha$ Forest Cross-Correlation
• Probing Large Scale Ionizing Background Fluctuation with Lyman $\alpha$ Forest and Galaxy Cross-correlation at z=2.4
• Photometric IGM tomography with Subaru/HSC: the large-scale structure of Ly$\alpha$ emitters and IGM transmission in the COSMOS field at $z\sim 5$
• Separating the memory of reionization from cosmology in the Ly$\alpha$ forest power spectrum at the post-reionization era
• The long-lasting effect of X-ray preheating in the post-reionization intergalactic medium
• The Compressed 3D Lyman-Alpha Forest Bispectrum
• The effect of ionizing background fluctuations on the spatial correlations of high redshift Ly$\alpha$-emitting galaxies
• The effect of helium reionization on the Lyman-alpha forest hydrogen flux statistics
• Generation of Lognormal Synthetic Lyman-$\alpha$ Forest Spectra for $P_{1D}$ Analysis