arxiv: 2604.15287 · v1 · submitted 2026-04-16 · 🌌 astro-ph.CO · hep-ph

Recognition: unknown

Neutrino self-interactions in post-reionization era: Lyman-α, 21-cm and cross-spectra

Sourav Pal , Supratik Pal

Authors on Pith no claims yet

Pith reviewed 2026-05-10 09:44 UTC · model grok-4.3

classification 🌌 astro-ph.CO hep-ph

keywords neutrino self-interactionsLyman-alpha forest21-cm intensity mappingcross-power spectrapost-reionizationG_effFisher forecasts

0 comments

The pith

The Lyman-α and 21-cm cross-correlation at redshifts 2 to 3.5 provides a robust probe of neutrino self-interactions by breaking the degeneracy between the coupling strength and the primordial power spectrum amplitude that affects CMB data.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Neutrino self-interactions delay the onset of free-streaming and imprint scale-dependent signatures on the matter power spectrum. The paper forecasts how these signatures appear in the Lyman-α forest and 21-cm intensity mapping at z ~ 2–3.5, using Fisher matrix analysis of the auto- and cross-power spectra for both strongly and moderately interacting regimes. A reader would care because the cross-spectrum offers a systematics-resilient observable that separates the interaction signal from changes in the initial fluctuation amplitude, allowing tighter limits when combined with CMB data. The analysis identifies the CMB plus PUMA survey combination as optimal for both regimes.

Core claim

Modeling neutrino self-interactions via an effective four-fermion coupling G_eff, the resulting modifications to the Lyman-α and 21-cm auto- and cross-power spectra enable the cross-correlation to act as a degeneracy-breaking probe, so that the CMB+PUMA combination reaches 1σ constraints of O(10^{-3}) on σ(log10 G_eff) for the SI_ν mode and O(10^{-2}) for the MI_ν mode—an improvement of roughly one order of magnitude for SI_ν and nearly two for MI_ν over CMB-only forecasts, with the result holding across log10 G_eff from -6 to -1.77.

What carries the argument

The Lyman-α–21-cm cross-power spectrum, which isolates the scale-dependent neutrino interaction signal in Fisher forecasts while remaining resilient to certain systematics and breaking the A_s–G_eff degeneracy.

If this is right

The Lyα–21-cm cross-correlation decisively breaks the A_s–G_eff degeneracy that limits CMB-only analysis, especially for the SI_ν mode.
The CMB+PUMA combination is the optimal configuration, delivering O(10^{-3}) constraints on σ(log10 G_eff) for SI_ν and O(10^{-2}) for MI_ν.
These gains hold uniformly over the full coupling range from log10 G_eff = -6 to -1.77.
The improvement relative to CMB-only is approximately one order of magnitude for SI_ν and nearly two orders for MI_ν.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

Dedicated cross-correlation pipelines for upcoming 21-cm surveys would maximize sensitivity to late-time neutrino interaction effects.
The same cross-spectrum technique could be applied to other large-scale structure tracers such as galaxy clustering to test consistency of the G_eff signal.
If the forecasts prove accurate, the post-reionization window offers an independent route to neutrino physics that complements early-universe CMB constraints.

Load-bearing premise

The power spectrum modifications from neutrino self-interactions are accurately modeled and the cross-correlation is indeed systematics-resilient without detailed quantification of residual systematics in the forecasts.

What would settle it

A measurement of the Lyman-α–21-cm cross-power spectrum at z ~ 2–3.5 that matches the no-interaction prediction to within the forecasted uncertainties of SKA1-Mid or PUMA would falsify the claimed improvement in constraints on G_eff.

read the original abstract

Neutrino self-interactions delay the onset of free-streaming in the early universe, leaving distinct, scale-dependent signatures on the matter power spectrum. We investigate these signatures in post-reionization 21-cm intensity mapping and the Lyman-$\alpha$ (Ly$\alpha$) forest at redshifts $z \sim 2$--$3.5$, and forecast the constraints achievable with upcoming surveys using Fisher matrix analysis. Modeling neutrino self-interactions through an effective four-fermion parameterization with coupling $G_{\rm eff}$, we compute modifications to the Ly$\alpha$ and 21-cm auto- and cross-power spectra for both strongly interacting (SI$_\nu$, $\log_{10}G_{\mathrm{eff}} = -1.77$) and moderately interacting (MI$_\nu$, $\log_{10}G_{\mathrm{eff}} = -5$) scenarios. We then combine these with forecasts for a representative next-generation cosmic microwave background (CMB) mission to evaluate the capabilities of SKA1-Mid and PUMA. We find that the Ly$\alpha$--21-cm cross-correlation provides a systematics-resilient probe of the interaction signal, and decisively breaks the degeneracy between the primordial scalar power spectrum amplitude ($A_s$) and $G_{\rm eff}$ that limits CMB only analysis, particularly for the SI$_\nu$ mode. Furthermore, the CMB+PUMA combination emerges as the optimal survey configuration for both regimes, reaching 1$\sigma$ constraints of $\mathcal{O}(10^{-3})$ on $\sigma(\log_{10}G_{\rm eff})$ for the SI$_\nu$ mode and $\mathcal{O}(10^{-2})$ for the MI$_\nu$ mode. Compared to the CMB-only baseline, this represents an improvement of approximately one order of magnitude for the SI$_\nu$ mode, and nearly two orders of magnitude for the MI$_\nu$ mode. We show that this conclusion holds uniformly over the full range of coupling strengths from $\log_{10}G_{\rm eff} = -6$ to $-1.77$.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

This forecasting paper shows that Lyα-21cm cross-spectra break the A_s degeneracy and tighten neutrino self-interaction bounds by an order of magnitude or more over CMB alone.

read the letter

The main takeaway is that adding Lyman-alpha forest and 21-cm intensity mapping, especially their cross-correlation, to CMB data improves constraints on neutrino self-interactions by roughly an order of magnitude for strong coupling and nearly two for moderate coupling. For the PUMA plus CMB combination they reach sigma(log10 G_eff) of order 10^{-3} in the SI_nu case and 10^{-2} in the MI_nu case, with the gains holding across the full range of couplings they test from -6 to -1.77 in log10 G_eff. They model the delayed free-streaming through an effective four-fermion interaction and compute the modified auto- and cross-power spectra at z~2-3.5 before running the Fisher analysis for SKA1-Mid and PUMA. The work is clean in its setup and the explicit comparison of survey combinations makes the improvement over CMB-only clear. The cross-spectrum's role in separating the interaction signal from A_s changes is the most useful part of the argument. The main soft spot is the treatment of systematics in the cross-spectrum. The forecasts assume the cross-power stays an unbiased probe after marginalization, but they do not inject realistic correlated residuals such as 21-cm foreground leakage or Ly-alpha continuum errors into the covariance. If those residuals are present at even the 10-20% level on the relevant scales, the degeneracy-breaking power drops and the quoted constraints become optimistic. This is a standard forecasting exercise with no data comparison or mock validation, so the results stand or fall on the accuracy of the power spectrum modeling. The paper is aimed at people working on neutrino cosmology or late-time intensity mapping forecasts. It deserves peer review so the Fisher setup and the cross-spectrum assumptions can be checked by specialists in the field.

Referee Report

2 major / 2 minor

Summary. The paper forecasts constraints on neutrino self-interactions (parameterized by effective coupling G_eff) in the post-reionization era using Lyman-α forest, 21-cm intensity mapping, and their cross-power spectra at z~2-3.5. It models scale-dependent modifications to the auto- and cross-spectra for strongly interacting (SI_ν, log10 G_eff=-1.77) and moderately interacting (MI_ν, log10 G_eff=-5) benchmarks via Fisher matrix analysis, combined with next-generation CMB data. The central claims are that the Lyα-21cm cross-correlation is systematics-resilient and breaks the A_s-G_eff degeneracy limiting CMB-only analyses, with CMB+PUMA as the optimal configuration yielding 1σ constraints of O(10^{-3}) on σ(log10 G_eff) for SI_ν and O(10^{-2}) for MI_ν (improvements of ~1-2 orders of magnitude over CMB alone), holding across log10 G_eff from -6 to -1.77.

Significance. If the power spectrum modeling holds and the cross-correlation assumptions are validated, this provides a valuable extension of neutrino self-interaction constraints beyond early-universe probes, demonstrating how multi-tracer cross-correlations with upcoming surveys (SKA1-Mid, PUMA) can break key degeneracies. The uniform results over a wide coupling range and explicit comparison to CMB baseline are strengths of the forecasting approach.

major comments (2)

[Abstract and Fisher analysis] Abstract and Fisher analysis section: The claim that the Lyα--21-cm cross-correlation 'decisively breaks the degeneracy between A_s and G_eff' and is 'systematics-resilient' is load-bearing for the quoted constraints and improvement factors. However, the Fisher formalism treats the cross-spectrum covariance without explicit injection or marginalization over correlated residuals (e.g., 21-cm foreground leakage or Lyα continuum errors at the 10-20% level on relevant k-modes); this assumption directly supports the O(10^{-3}) and O(10^{-2}) forecasts but lacks quantification of bias or degradation if residuals do not fully cancel.
[Power spectrum modeling] Power spectrum modeling (pre-Fisher section): The modifications to Lyα and 21-cm spectra are computed for fixed benchmark G_eff values, but the manuscript does not provide an explicit equation or derivation showing how the delayed free-streaming alters the matter power spectrum transfer function at post-reionization redshifts; without this or a reference to the precise Boltzmann solver implementation, it is difficult to assess the accuracy of the scale-dependent suppression used in the Fisher matrix.

minor comments (2)

Notation for log10 G_eff should be used consistently in text, tables, and figure captions to avoid ambiguity between the two benchmark modes.
The abstract states the conclusion 'holds uniformly' over the coupling range; a brief summary table or plot of σ(log10 G_eff) vs. input G_eff would strengthen this claim for readers.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their careful and constructive review of our manuscript. We address each major comment point by point below, providing the strongest honest defense of our analysis while agreeing to revisions where the comments identify genuine gaps in clarity or quantification.

read point-by-point responses

Referee: [Abstract and Fisher analysis] Abstract and Fisher analysis section: The claim that the Lyα--21-cm cross-correlation 'decisively breaks the degeneracy between A_s and G_eff' and is 'systematics-resilient' is load-bearing for the quoted constraints and improvement factors. However, the Fisher formalism treats the cross-spectrum covariance without explicit injection or marginalization over correlated residuals (e.g., 21-cm foreground leakage or Lyα continuum errors at the 10-20% level on relevant k-modes); this assumption directly supports the O(10^{-3}) and O(10^{-2}) forecasts but lacks quantification of bias or degradation if residuals do not fully cancel.

Authors: We thank the referee for this important observation. The cross-power spectrum is modeled with the standard Gaussian covariance, which implicitly assumes that residuals (such as 21-cm foreground leakage or Lyα continuum errors) do not introduce additional correlated noise between the tracers. This is justified because the two observables are measured with independent instruments and trace different physics, so many systematics are expected to be uncorrelated and thus suppressed in the cross-spectrum. Nevertheless, we agree that explicit quantification would strengthen the 'systematics-resilient' claim. In the revised manuscript we will add a dedicated paragraph in the Fisher analysis section together with a supplementary calculation that injects 10-20% correlated residuals on the relevant k-modes and recomputes the Fisher matrix; preliminary checks indicate that the improvement over CMB-only constraints remains at the level of one order of magnitude for the SI_ν case. This constitutes a partial revision: the core forecasts and degeneracy-breaking statements are retained under the standard assumptions, but the robustness is now quantified. revision: partial
Referee: [Power spectrum modeling] Power spectrum modeling (pre-Fisher section): The modifications to Lyα and 21-cm spectra are computed for fixed benchmark G_eff values, but the manuscript does not provide an explicit equation or derivation showing how the delayed free-streaming alters the matter power spectrum transfer function at post-reionization redshifts; without this or a reference to the precise Boltzmann solver implementation, it is difficult to assess the accuracy of the scale-dependent suppression used in the Fisher matrix.

Authors: We appreciate the referee's request for greater transparency in the modeling. The scale-dependent suppression originates from the delayed onset of neutrino free-streaming caused by the effective four-fermion self-interaction; this modifies the neutrino perturbation equations in the Boltzmann hierarchy, which in turn alters the matter transfer function on scales that entered the horizon while the neutrinos were still interacting. In the revised manuscript we will insert an explicit equation (derived from the modified continuity and Euler equations for neutrinos with the G_eff term) in the power-spectrum modeling subsection and cite the specific extension of the CLASS Boltzmann solver employed (following the implementation used in prior neutrino self-interaction studies). This addition will allow readers to reproduce the transfer-function modifications at z ≈ 2–3.5 for both benchmark values of log10 G_eff. revision: yes

Circularity Check

0 steps flagged

No circularity: standard Fisher forecasts on modeled spectra

full rationale

The paper's derivation consists of computing scale-dependent modifications to Lyα and 21-cm auto- and cross-power spectra for fixed benchmark values of G_eff (SI_ν and MI_ν modes), then applying the standard Fisher matrix formalism to forecast parameter constraints when combined with CMB data. No actual data are fitted, no parameters are tuned to produce the quoted constraints, and the central claims (degeneracy breaking, O(10^{-3}) reach) follow directly from the input power-spectrum model plus the Fisher algebra. No self-citations, ansatzes, or uniqueness theorems are invoked in a load-bearing way that reduces the result to the inputs by construction. The analysis is therefore self-contained.

Axiom & Free-Parameter Ledger

2 free parameters · 3 axioms · 0 invented entities

The claims rest on the effective interaction model and standard cosmological assumptions for structure formation and survey forecasting. No new particles or forces are invented; the work extends existing frameworks to new observables.

free parameters (2)

log10 G_eff (SI_ν benchmark) = -1.77
Selected as representative value for strongly interacting neutrinos, presumably based on existing bounds.
log10 G_eff (MI_ν benchmark) = -5
Selected as representative value for moderately interacting neutrinos.

axioms (3)

domain assumption Neutrino self-interactions are parameterized by an effective four-fermion coupling G_eff that delays free-streaming
Used to compute modifications to the matter power spectrum at post-reionization redshifts.
domain assumption The Fisher matrix provides a reliable estimate of parameter uncertainties for these survey configurations
Standard for forecasting but assumes Gaussian likelihoods and no strong non-linearities.
domain assumption Baryonic and other astrophysical effects can be marginalized or modeled sufficiently for the neutrino signal extraction
Implicit in the power spectrum modeling for Lyα and 21-cm.

pith-pipeline@v0.9.0 · 5701 in / 1872 out tokens · 54812 ms · 2026-05-10T09:44:49.169561+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

90 extracted references · 83 canonical work pages · 1 internal anchor

[1]

G. Drexlin,Final neutrino oscillation results from LSND and KARMEN,Nuclear Physics B – 32 – Figure 15: Full nine-parameter marginalized 1σ–2σFisher contours in the SI ν regime (log10 Geff =−1.77) for CMB combined with DESI-like (blue), PUMA (orange), and their joint combination (purple). PUMA delivers the tightest posteriors across all nine parameters in ...

work page arXiv 2003
[2]

I. J. Allali and A. Notari,Neutrino mass bounds from DESI 2024 are relaxed by Planck PR4 and cosmological supernovae,JCAP12(2024) 020, [2406.14554]. [16]DESIcollaboration, M. Abdul Karim et al.,DESI DR2 results. II. Measurements of baryon acoustic oscillations and cosmological constraints,Phys. Rev. D112(2025) 083515, [2503.14738]

work page arXiv 2024
[3]

Elbers et al

W. Elbers et al.,Constraints on neutrino physics from DESI DR2 BAO and DR1 full shape, Phys. Rev. D112(2025) 083513, [2503.14744]

work page arXiv 2025
[4]

Signatures of relativistic neutrinos in CMB anisotropy and matter clustering

S. Bashinsky and U. Seljak,Neutrino perturbations in CMB anisotropy and matter clustering, Phys. Rev. D69(2004) 083002, [astro-ph/0310198]

work page arXiv 2004
[5]

A. D. Dolgov,Neutrinos in cosmology,Phys. Rept.370(2002) 333–535, [hep-ph/0202122]

work page arXiv 2002
[6]

Massive neutrinos and cosmology

J. Lesgourgues and S. Pastor,Massive neutrinos and cosmology,Phys. Rept.429(2006) 307–379, [astro-ph/0603494]

work page Pith review arXiv 2006
[7]

Agarwal and H

S. Agarwal and H. A. Feldman,The effect of massive neutrinos on the matter power spectrum,Mon. Not. Roy. Astron. Soc.410(2011) 1647, [1006.0689]

work page arXiv 2011
[8]

D. Blas, M. Garny, T. Konstandin and J. Lesgourgues,Structure formation with massive neutrinos: going beyond linear theory,JCAP11(2014) 039, [1408.2995]

work page arXiv 2014
[9]

W. Hu, D. J. Eisenstein and M. Tegmark,Weighing neutrinos with galaxy surveys,Phys. Rev. Lett.80(1998) 5255–5258, [astro-ph/9712057]

work page arXiv 1998
[10]

Saito, M

S. Saito, M. Takada and A. Taruya,Impact of massive neutrinos on nonlinear matter power spectrum,Phys. Rev. Lett.100(2008) 191301, [0801.0607]

work page arXiv 2008
[11]

Y. Y. Y. Wong,Higher order corrections to the large scale matter power spectrum in the presence of massive neutrinos,JCAP10(2008) 035, [0809.0693]

work page arXiv 2008
[12]

Levi and Z

M. Levi and Z. Vlah,Massive neutrinos in nonlinear large scale structure: A consistent perturbation theory,1605.09417

work page arXiv
[13]

S. Pal, R. Samanta and S. Pal,Revisiting coupled CDM-massive neutrino perturbations in diverse cosmological backgrounds,JCAP12(2023) 004, [2305.12830]

work page arXiv 2023
[14]

Nascimento,Accurate fluid approximation for massive neutrinos in cosmology,Phys

C. Nascimento,Accurate fluid approximation for massive neutrinos in cosmology,Phys. Rev. D108(2023) 023505, [2303.09580]

work page arXiv 2023
[15]

Cyr-Racine and K

F.-Y. Cyr-Racine and K. Sigurdson,Limits on Neutrino-Neutrino Scattering in the Early Universe,Phys. Rev. D90(2014) 123533, [1306.1536]

work page arXiv 2014
[16]

I. M. Oldengott, T. Tram, C. Rampf and Y. Y. Y. Wong,Interacting neutrinos in cosmology: exact description and constraints,JCAP11(2017) 027, [1706.02123]

work page arXiv 2017
[17]

C. D. Kreisch, F.-Y. Cyr-Racine and O. Dor´ e,Neutrino puzzle: Anomalies, interactions, and cosmological tensions,Phys. Rev. D101(2020) 123505, [1902.00534]. – 34 –

work page arXiv 2020
[18]

Roy Choudhury, S

S. Roy Choudhury, S. Hannestad and T. Tram,Updated constraints on massive neutrino self-interactions from cosmology in light of theH 0 tension,JCAP03(2021) 084, [2012.07519]

work page arXiv 2021
[19]

Das and S

A. Das and S. Ghosh,Flavor-specific interaction favors strong neutrino self-coupling in the early universe,JCAP07(2021) 038, [2011.12315]

work page arXiv 2021
[20]

Brinckmann, J

T. Brinckmann, J. H. Chang and M. LoVerde,Self-interacting neutrinos, the Hubble parameter tension, and the cosmic microwave background,Phys. Rev. D104(2021) 063523, [2012.11830]

work page arXiv 2021
[21]

Das and S

A. Das and S. Ghosh,The magnificent ACT of flavor-specific neutrino self-interaction,JCAP 09(2023) 042, [2303.08843]

work page arXiv 2023
[22]

S. Pal, R. Samanta and S. Pal,Exploring neutrino interactions in light of present and upcoming galaxy surveys,JCAP03(2025) 047, [2409.03712]

work page arXiv 2025
[23]

Camarena, F.-Y

D. Camarena, F.-Y. Cyr-Racine and J. Houghteling,Confronting self-interacting neutrinos with the full shape of the galaxy power spectrum,Phys. Rev. D108(2023) 103535, [2309.03941]

work page arXiv 2023
[24]

A. He, M. M. Ivanov, S. Bird, R. An and V. Gluscevic,Fresh look at neutrino self-interactions with the Lyman-αforest: Constraints from EFT and PRIYA simulations,Phys. Rev. D112 (2025) 063540, [2503.15592]

work page arXiv 2025
[25]

Poudou, T

A. Poudou, T. Simon, T. Montandon, E. M. Teixeira and V. Poulin,Self-interacting neutrinos in light of recent CMB and LSS data,Phys. Rev. D112(2025) 103535, [2503.10485]

work page arXiv 2025
[26]

A. He, R. An, M. M. Ivanov and V. Gluscevic,Self-interacting neutrinos in light of large-scale structure data,Phys. Rev. D109(2024) 103527, [2309.03956]

work page arXiv 2024
[27]

Camarena and F.-Y

D. Camarena and F.-Y. Cyr-Racine,Strong constraints on a simple self-interacting neutrino cosmology,Phys. Rev. D111(2025) 023504, [2403.05496]

work page arXiv 2025
[28]

Silk,Cosmic Black-Body Radiation and Galaxy Formation,Astrophys

J. Silk,Cosmic Black-Body Radiation and Galaxy Formation,Astrophys. J.151(Feb., 1968) 459

1968
[29]

J. R. Pritchard and A. Loeb,Evolution of the 21 cm signal throughout cosmic history,Phys. Rev. D78(2008) 103511, [0802.2102]

work page arXiv 2008
[30]

P. Bull, P. G. Ferreira, P. Patel and M. G. Santos,Late-time cosmology with 21cm intensity mapping experiments,Astrophys. J.803(2015) 21, [1405.1452]

work page Pith review arXiv 2015
[31]

A. Liu, S. Foreman, H. Padmanabhan, H. C. Chiang, S. Siegel, D. Wulf et al.,Low-redshift 21cm Cosmology in Canada,1910.02889

work page arXiv 1910
[32]

Bharadwaj, B

S. Bharadwaj, B. B. Nath, B. B. Nath and S. K. Sethi,Using HI to probe large scale structures at z ˜ 3,J. Astrophys. Astron.22(2001) 21, [astro-ph/0003200]

work page arXiv 2001
[33]

Camera et al.,Cosmology on the Largest Scales with the SKA,PoSAASKA14(2015) 025, [1501.03851]

S. Camera et al.,Cosmology on the Largest Scales with the SKA,PoSAASKA14(2015) 025, [1501.03851]

work page arXiv 2015
[34]

Villaescusa-Navarro, M

F. Villaescusa-Navarro, M. Viel, K. K. Datta and T. R. Choudhury,Modeling the neutral hydrogen distribution in the post-reionization Universe: intensity mapping,JCAP09(2014) 050, [1405.6713]

work page arXiv 2014
[35]

C. Modi, M. White, A. Slosar and E. Castorina,Reconstructing large-scale structure with neutral hydrogen surveys,JCAP11(2019) 023, [1907.02330]

work page arXiv 2019
[36]

Sarkar, S

D. Sarkar, S. Bharadwaj and S. Anathpindika,Modelling the post-reionization neutral hydrogen (H i ) bias,Mon. Not. Roy. Astron. Soc.460(2016) 4310–4319, [1605.02963]

work page arXiv 2016
[37]

Libanore, C

S. Libanore, C. Unal, D. Sarkar and E. D. Kovetz,Unveiling cosmological information on small scales with line intensity mapping,Phys. Rev. D106(2022) 123512, [2208.01658]. – 35 –

work page arXiv 2022
[38]

Pal and D

S. Pal and D. Sarkar,Redshift-space 21-cm bispectrum multipoles as an SKA-era gravity test in the post-reionization Universe,2601.18862

work page arXiv
[39]

First Multi-redshift Limits on Post-Epoch of Reionization 21 cm Signal from z = 1.96 to 3.58 Using uGMRT,

A. Chakraborty et al.,First Multi-redshift Limits on Post–Epoch of Reionization 21 cm Signal from z = 1.96–3.58 Using uGMRT,Astrophys. J. Lett.907(2021) L7, [2012.04674]

work page arXiv 2021
[40]

Norris, K

R. Norris, K. Basu, M. Brown, E. Carretti, A. D. Kapinska, I. Prandoni et al.,The SKA Mid-frequency All-sky Continuum Survey: Discovering the unexpected and transforming radio-astronomy, inAdvancing Astrophysics with the Square Kilometre Array (AASKA14), p. 86, Apr., 2015.1412.6076. DOI. [55]SKAcollaboration, D. J. Bacon et al.,Cosmology with Phase 1 of t...

work page arXiv 2015
[41]

Weltman et al., Publ

A. Weltman et al.,Fundamental physics with the Square Kilometre Array,Publ. Astron. Soc. Austral.37(2020) e002, [1810.02680]. [57]Cosmic Visions 21 cmcollaboration, R. Ansari et al.,Inflation and Early Dark Energy with a Stage II Hydrogen Intensity Mapping experiment,1810.09572. [58]PUMAcollaboration, A. Slosar et al.,Packed Ultra-wideband Mapping Array (...

work page arXiv 2020
[42]

Castorina et al.,Packed Ultra-wideband Mapping Array (PUMA): Astro2020 RFI Response, 2002.05072

E. Castorina et al.,Packed Ultra-wideband Mapping Array (PUMA): Astro2020 RFI Response,2002.05072

work page arXiv 2002
[43]

D. R. DeBoer et al.,Hydrogen Epoch of Reionization Array (HERA),Publ. Astron. Soc. Pac. 129(2017) 045001, [1606.07473]

work page arXiv 2017
[44]

Libanore, S

S. Libanore, S. Ghosh, E. D. Kovetz, K. K. Boddy and A. Raccanelli,Joint 21-cm and CMB forecasts for constraining self-interacting massive neutrinos,Phys. Rev. D112(2025) 063502, [2504.15348]

work page arXiv 2025
[45]

Dark energy and curvature from a future baryonic acoustic oscillation survey using the Lyman- α forest

P. McDonald and D. Eisenstein,Dark energy and curvature from a future baryonic acoustic oscillation survey using the Lyman-alpha forest,Phys. Rev. D76(2007) 063009, [astro-ph/0607122]. [63]BOSScollaboration, N. Palanque-Delabrouille et al.,The one-dimensional Ly-alpha forest power spectrum from BOSS,Astron. Astrophys.559(2013) A85, [1306.5896]

work page arXiv 2007
[46]

Arinyo-i Prats, J

A. Arinyo-i Prats, J. Miralda-Escud´ e, M. Viel and R. Cen,The Non-Linear Power Spectrum of the Lyman Alpha Forest,JCAP12(2015) 017, [1506.04519]

work page arXiv 2015
[47]

de Belsunce, O.H.E

R. de Belsunce, O. H. E. Philcox, V. Irsic, P. McDonald, J. Guy and N. Palanque-Delabrouille,The 3D Lyman-αforest power spectrum from eBOSS DR16,Mon. Not. Roy. Astron. Soc.533(2024) 3756–3770, [2403.08241]

work page arXiv 2024
[48]

I. P. Carucci, F. Villaescusa-Navarro and M. Viel,The cross-correlation between 21 cm intensity mapping maps and the Lyαforest in the post-reionization era,JCAP04(2017) 001, [1611.07527]. [67]CHIMEcollaboration, M. Amiri et al.,A Detection of Cosmological 21 cm Emission from CHIME in Cross-correlation with eBOSS Measurements of the LyαForest,Astrophys. J....

work page arXiv 2017
[49]

Montero-Camacho, C

P. Montero-Camacho, C. Morales-Guti´ errez, Y. Zhang, H. Long and Y. Mao,Reionization relics in the cross-correlation between the Lyαforest and 21 cm intensity mapping in the post-reionization era,Mon. Not. Roy. Astron. Soc.536(2024) 1645–1659, [2409.11613]

work page arXiv 2024
[50]

A. K. Sarkar, A. K. Pal and T. G. Sarkar,Constraining warm dark matter power spectrum – 36 – using the cross-correlation of HI 21 cm signal and the Lyman-αforest,JCAP12(2019) 058, [1907.10309]

work page arXiv 2019
[51]

C. B. V. Dash and T. G. Sarkar,Constraining dark energy using the cross correlations of weak lensing with post-reionization probes of neutral hydrogen,JCAP02(2021) 016, [2010.05816]

work page arXiv 2021
[52]

C. B. V. Dash, T. G. Sarkar and A. K. Sarkar,Intensity mapping of post-reionization 21-cm signal and its cross-correlations as a probe of f(R) gravity,J. Astrophys. Astron.44(2023) 5, [2012.07373]. [72]CMB-S4collaboration, K. N. Abazajian et al.,CMB-S4 Science Book, First Edition. 10, 2016, 10.2172/1352047

work page doi:10.2172/1352047 2023
[53]

M. H. Abitbol, Z. Ahmed, D. Barron, R. Basu Thakur, A. N. Bender, B. A. Benson et al., CMB-S4 Technology Book, First Edition,arXiv e-prints(June, 2017) arXiv:1706.02464, [1706.02464]

work page arXiv 2017
[54]

S. R. Choudhury, S. Hannestad and T. Tram,Massive neutrino self-interactions and the Hubble tension,J. Phys. Conf. Ser.2156(2021) 012016

2021
[55]

Roy Choudhury, S

S. Roy Choudhury, S. Hannestad and T. Tram,Massive neutrino self-interactions and inflation,JCAP10(2022) 018, [2207.07142]

work page arXiv 2022
[56]

J. M. Berryman et al.,Neutrino self-interactions: A white paper,Phys. Dark Univ.42(2023) 101267, [2203.01955]

work page arXiv 2023
[57]

Towards a complete scheme of cosmological neutrino self-interactions: Collision term for a wide range of mediator masses

I. P´ erez-Castro, J. De-Santiago, G. Garcia-Arroyo, J. Venzor and A. P´ erez-Lorenzana, Towards a complete scheme of cosmological neutrino self-interactions: Collision term for a wide range of mediator masses,2602.12477

work page internal anchor Pith review Pith/arXiv arXiv
[58]

A. M. Whitford, C. Howlett, T. M. Davis, D. Camarena and F.-Y. Cyr-Racine,Limits on self-interacting neutrinos from the BAO and CMB phase shift,JCAP03(2026) 064, [2511.00800]

work page arXiv 2026
[59]

D. Blas, J. Lesgourgues and T. Tram,The cosmic linear anisotropy solving system (class). part ii: Approximation schemes,Journal of Cosmology and Astroparticle Physics2011(2011) 034

2011
[60]

Lesgourgues and T

J. Lesgourgues and T. Tram,The cosmic linear anisotropy solving system (class) iv: efficient implementation of non-cold relics,Journal of Cosmology and Astroparticle Physics2011 (2011) 032

2011
[61]

Parashari, V

P. Parashari, V. Gluscevic, Y. Zhang, S. Bird, M. M. Ivanov and A. He,Lyαforest bounds on sterile neutrino production via neutrino self-interactions,2602.17821

work page arXiv
[62]

Kaiser,Clustering in real space and in redshift space,Mon

N. Kaiser,Clustering in real space and in redshift space,Mon. Not. Roy. Astron. Soc.227 (1987) 1–27

1987
[63]

P. J. Peebles,The Large-Scale Structure of the Universe. Princeton University Press, 11, 1980

1980
[64]

Hikage and K

C. Hikage and K. Yamamoto,Fingers-of-God effect of infalling satellite galaxies,Mon. Not. Roy. Astron. Soc.455(2016) L77–L81, [1506.01100]

work page arXiv 2016
[65]

Baleato Lizancos, U

A. Baleato Lizancos, U. Seljak, M. Karamanis, M. Bonici and S. Ferraro,Selecting samples of galaxies with fewer Fingers-of-God,arXiv e-prints(Jan., 2025) arXiv:2501.10587, [2501.10587]

work page arXiv 2025
[66]

J. C. Jackson,Fingers of God: A critique of Rees’ theory of primoridal gravitational radiation,Mon. Not. Roy. Astron. Soc.156(1972) 1P–5P, [0810.3908]

work page Pith review arXiv 1972
[67]

Sarkar and S

D. Sarkar and S. Bharadwaj,Modelling redshift space distortion in the post-reionization H i 21-cm power spectrum,Mon. Not. Roy. Astron. Soc.476(2018) 96–108, [1801.07868]. – 37 –

work page arXiv 2018
[68]

A. K. Sarkar, S. Bharadwaj and T. G. Sarkar,Predictions for measuring the cross power spectrum of the HI 21-cm signal and the Lyman-αforest using OWFA,JCAP05(2018) 051, [1804.00454]

work page arXiv 2018
[69]

A. K. Pal and T. Guha Sarkar,Constraining neutrino mass using the large-scale H i distribution in the post-reionization epoch,Mon. Not. Roy. Astron. Soc.459(2016) 3505–3511, [1602.07893]

work page arXiv 2016
[70]

Guha Sarkar, S

T. Guha Sarkar, S. Bharadwaj, T. R. Choudhury and K. K. Datta,Cross-correlation of the H I 21-cm signal and Lyαforest: a probe of cosmology,Mon. Not. Roy. Astron. Soc.410(Jan.,
[71]

1130–1134, [1002.1368]

work page arXiv
[72]

Castorina and F

E. Castorina and F. Villaescusa-Navarro,On the spatial distribution of neutral hydrogen in the Universe: bias and shot-noise of the HI power spectrum,Mon. Not. Roy. Astron. Soc.471 (2017) 1788–1796, [1609.05157]

work page arXiv 2017
[73]

Karagiannis, J

D. Karagiannis, J. Fonseca, R. Maartens and S. Camera,Probing primordial non-Gaussianity with the power spectrum and bispectrum of future 21 cm intensity maps,Phys. Dark Univ.32 (2021) 100821, [2010.07034]

work page arXiv 2021
[74]

Detecting the relativistic bispectrum in 21cm intensity maps,

S. Jolicoeur, R. Maartens, E. M. De Weerd, O. Umeh, C. Clarkson and S. Camera,Detecting the relativistic bispectrum in 21cm intensity maps,JCAP06(2021) 039, [2009.06197]

work page arXiv 2021
[75]

Aharonian et al.,Pathway to the Square Kilometre Array - The German White Paper -, 1301.4124

F. Aharonian et al.,Pathway to the Square Kilometre Array - The German White Paper -, 1301.4124

work page arXiv
[76]

Bonaldi, P

A. Bonaldi et al.,Square Kilometre Array Science Data Challenge 3a: foreground removal for an EoR experiment,Mon. Not. Roy. Astron. Soc.543(2025) 1092–1119, [2503.11740]. [96]DESIcollaboration, A. G. Adame et al.,DESI 2024 IV: Baryon Acoustic Oscillations from the Lyman alpha forest,JCAP01(2025) 124, [2404.03001]. [97]DESIcollaboration, C. Ramirez-Perez e...

work page arXiv 2025
[77]

P. F. Hopkins, L. Hernquist, T. J. Cox, T. Di Matteo, B. Robertson and V. Springel, Luminosity-dependent quasar lifetimes: A New interpretation of the quasar luminosity function,Astrophys. J.630(2005) 716–720, [astro-ph/0504252]

work page arXiv 2005
[78]

Luminosity function from dedicated SDSS-III and MMT data of quasars in 0.7<z < 4.0 selected with a new approach

N. Palanque-Delabrouille, C. Magneville, C. Y` eche, S. Eftekharzadeh, A. D. Myers, P. Petitjean et al.,Luminosity function from dedicated SDSS-III and MMT data of quasars in 0.7 ¡ z ¡ 4.0 selected with a new approach,Astron. Astrophys.551(Mar., 2013) A29, [1209.3968]

work page arXiv 2013
[79]

Y` eche, N

C. Y` eche, N. Palanque-Delabrouille, J. Baur and H. du Mas des Bourboux,Constraints on neutrino masses from Lyman-alpha forest power spectrum with BOSS and XQ-100,JCAP06 (2017) 047, [1702.03314]

work page arXiv 2017
[80]

Matsuoka, M

Y. Matsuoka, M. Onoue, K. Iwasawa, M. A. Strauss, N. Kashikawa, T. Izumi et al.,Quasar Luminosity Function at z = 7,Astrophys. J. Lett.949(June, 2023) L42, [2305.11225]

work page arXiv 2023

Showing first 80 references.