halo power spectrum and bispectrum in the effective field
play

Halo Power Spectrum and Bispectrum in the Effective Field Theory of - PowerPoint PPT Presentation

Halo Power Spectrum and Bispectrum in the Effective Field Theory of Large Scale Structures Zvonimir Vlah Stanford University & SLAC with: Raul Angulo (CEFCA), Matteo Fasiello (Stanford), Leonardo Senatore (Stanford) Contents


  1. Halo Power Spectrum and Bispectrum in the Effective Field Theory of Large Scale Structures Zvonimir Vlah Stanford University & SLAC with: Raul Angulo (CEFCA), Matteo Fasiello (Stanford), Leonardo Senatore (Stanford)

  2. Contents ◮ Clustering of Dark Matter in EFT ◮ Clustering of DM Halos ◮ Earlier approaches ◮ EFT approach ◮ Halo Power Spectrum and Bispectrum Results ◮ Adding baryonic effects and non-Gaussianities ◮ Summary Biased Tracers in the EFT of LSS Contents 2 / 18

  3. & Gravitational clustering of dark matter Evolution of collisionless particles - Vlasov equation: d τ = ∂ f df ∂τ + 1 m p · ∇ f − am ∇ φ · ∇ p f = 0 , and ∇ 2 φ = 3/2 H Ω m δ. Integral moments of the distribution function: mass density field mean streaming velocity field � � d 3 p p i am f ( x , p ) ρ ( x ) = ma − 3 d 3 p f ( x , p ) , v i ( x ) = � d 3 p f ( x , p ) , Biased Tracers in the EFT of LSS Gravitational clustering of dark matter 3 / 18

  4. Gravitational clustering of dark matter Evolution of collisionless particles - Vlasov equation: d τ = ∂ f df ∂τ + 1 m p · ∇ f − am ∇ φ · ∇ p f = 0 , and ∇ 2 φ = 3/2 H Ω m δ. Eulerian framework - fluid approximation: ∂δ ∂τ + ∇ · [(1 + δ ) v ] = 0 ∂ v i ∂τ + H v i + v · ∇ v i = −∇ i φ − 1 ρ ∇ i ( ρσ ij ) , where σ ij is the velocity dispersion. Biased Tracers in the EFT of LSS Gravitational clustering of dark matter 3 / 18

  5. Gravitational clustering of dark matter Evolution of collisionless particles - Vlasov equation: d τ = ∂ f df ∂τ + 1 m p · ∇ f − am ∇ φ · ∇ p f = 0 , and ∇ 2 φ = 3/2 H Ω m δ. Eulerian framework - pressureless perfect fluid approximation: ∂δ ∂τ + ∇ · [(1 + δ ) v ] = 0 ∂ v i ∂τ + H v i + v · ∇ v i = −∇ i φ. Irrotational fluid: θ = ∇ · v . Biased Tracers in the EFT of LSS Gravitational clustering of dark matter 3 / 18

  6. Gravitational clustering of dark matter Evolution of collisionless particles - Vlasov equation: d τ = ∂ f df ∂τ + 1 m p · ∇ f − am ∇ φ · ∇ p f = 0 , and ∇ 2 φ = 3/2 H Ω m δ. EFT approach introduces a tress tensor for the long-distance fluid: ∂δ ∂τ + ∇ · [(1 + δ ) v ] = 0 ∂ v i ∂τ + H v i + v · ∇ v i = −∇ i φ − 1 ρ ∇ j ( τ ij ) , with given as τ ij = p 0 δ ij + c 2 s δρδ ij + O ( ∂ 2 δ, . . . ) [Carrasco et al. 2012] -derived by smoothing the short scales in the fluid with the smoothing filter W (Λ) . Biased Tracers in the EFT of LSS Gravitational clustering of dark matter 3 / 18

  7. EFTofLSS one-loop results for DM k 2 P EFT-1-loop = P 11 + P 1-loop − 2(2 π ) c 2 P 11 s (1) k 2 NL ���� � = ��� ���� � ������ / � ���� ���� ���� ���� � - ���� ��� ���� � - ���� ���� ��� �� - �������� � - ���� ���� �� - �������� ���� ��� ��� ��� ��� ��� ��� � [ � / ��� ] [first by Carrasco et al, 2012] ◮ Well defined and convergent expansion in k / k NL (one parameter). ◮ IR resummation (Lagrangian approach) - BAO peak! [Senatore et al, 2014] Biased Tracers in the EFT of LSS Gravitational clustering of dark matter 4 / 18

  8. Galaxies and biasing of dark matter halos Galaxies form at high density peaks of 3 initial matter density: 2 rare peaks exhibit higher clustering! overdensity 1 0 � 1 � 2 � 3 0 2 4 6 8 10 Λ� 1 � k ◮ Tracer detriments the amplitude: P g ( k ) = b 2 P m ( k ) + . . . ◮ Understanding bias is crucial for understanding the galaxy clustering [Tegmark et al, 2006] Biased Tracers in the EFT of LSS Galaxies and biasing of dark matter halos 5 / 18

  9. Earlier approaches to halo biasing Local biasing model: halo field is a function of just DM density field � � δ 2 �� δ 2 − + c δ 3 δ 3 + . . . δ h = c δ δ + c δ 2 [Fry & Gaztanaga, 1993] Non-local (in space) relation of the halo density field to the dark matter δ h ( x ) = c δ δ ( x ) + c δ 2 δ 2 ( x ) + c δ 3 δ 3 ( x ) [McDonald & Roy, 2008] + c s 2 s 2 ( x ) + c δ s 2 δ ( x ) s 2 ( x ) + c ψ ψ ( x ) + c st s ( x ) t ( x ) + c s 3 s 3 ( x ) + c ǫ ǫ + . . . , with effective ('Wilson') coefficients c l and variables: s ij ( x ) = ∂ i ∂ j φ ( x ) − 1 t ij ( x ) = ∂ i v j − 1 ij δ ( x ) , ij θ ( x ) − s ij ( x ) , 3 δ K 3 δ K ψ ( x ) = [ θ ( x ) − δ ( x )] − 2 7 s ( x ) 2 + 4 21 δ ( x ) 2 , where φ is the gravitational potential, and white noise (stochasticity) ǫ . Biased Tracers in the EFT of LSS Earlier modelling of halo bias 6 / 18

  10. Effective field theory of biasing Non-local (space and time) relation of the halo density field to the dark matter � t [Senatore 2014] dt ′ H ( t ′ ) [¯ δ h ( x , t ) ≃ c δ ( t , t ′ ) : δ ( x fl , t ′ ) : c δ 2 ( t , t ′ ) : δ ( x fl , t ′ ) 2 : +¯ c s 2 ( t , t ′ ) : s 2 ( x fl , t ′ ) : + ¯ c δ 3 ( t , t ′ ) : δ ( x fl , t ′ ) 3 : +¯ c δ s 2 ( t , t ′ ) : δ ( x fl , t ′ ) s 2 ( x fl , t ′ ) : + . . . + ¯ c ǫ ( t , t ′ ) ǫ ( x fl , t ′ ) + ¯ c ǫδ ( t , t ′ ) : ǫ ( x fl , t ′ ) δ ( x fl , t ′ ) : + . . . + ¯ � c ∂ 2 δ ( t , t ′ ) ∂ 2 x fl δ ( x fl , t ′ ) + . . . +¯ k 2 M Novice consideration of non-local in time formation, which depends on fields evaluated on past history on past path: � τ τ ′ d τ ′′ v ( τ ′′ , x fl ( x , τ, τ ′′ )) x fl ( x , τ, τ ′ ) = x − Biased Tracers in the EFT of LSS Effective field theory of biasing 7 / 18

  11. Effective field theory of biasing � 4 Pi � 1/3 , which can be different then k NL . ρ 0 New physical scale k M ∼ 2 π M 3 We look at the correlations at k ≪ k M . Each order in perturbation theory we get new bias coefficients: � � δ h ( k , t ) = c δ, 1 δ (1) ( k , t ) + flow terms � � δ (2) ( k , t ) + flow terms + c δ, 2 + . . . Emergence of degeneracy: choice of most convenient basis Turns out that at one loop 2-pt and tree level 3-pt function LIT and non-LIT are degenerate- this is no longer the case at higher loops or when 4-pt function is considered. Biased Tracers in the EFT of LSS Effective field theory of biasing 8 / 18

  12. Effective field theory of biasing Independent operators in the`Basis of Descendants': � � C (1) (1)st order: δ, 1 � � C (2) δ, 1 , C (2) δ, 2 , C (2) (2)nd order: δ 2 , 1 � � C (3) δ, 1 , C (3) δ, 2 , C (3) δ, 3 , C (3) δ 2 , 1 , C (3) δ 2 , 2 , C (3) δ 3 , 1 , C (3) δ, 3 cs C (3) (3)rd order: s 2 , 2 � � C ǫ , C (1) Stochastic: δǫ, 1 We compare P 1 − loop , P 1 − loop , B tree hhh , B tree hhm , B tree hmm statistics hh hm Renormalization! (takes care of short distance physics has at long distances of interest) In practice, ˜ c δ, 1 is a bare parameter, the sum of a finite part and a counterterm: c δ, 1 = ˜ c δ, 1 , finite + ˜ c δ, 1 , counter , ˜ After renormalization we end up with using 7 finite bias parameters b i (coefficients in EFT). Biased Tracers in the EFT of LSS Effective field theory of biasing 9 / 18

  13. Observables: P hm , P hh , B hmm , B hhm , B hhh Example: Halo-Matter Power Spectrum (one loop) � � d 3 q c (2) (2 π ) 3 F (2) P hm ( k ) = b δ, 1 ( t ) P 11 ( k ) + 2 ( k − q , q ) � δ, 1 , s ( k − q , q ) P 11 ( q ) P 11 ( | k − q | ) s � � � � d 3 q c (3) F (3) +3 P 11 ( k ) ( k , − q , q ) + � δ, 1 , s ( k , − q , q ) P 11 ( q ) s (2 π ) 3 � � � d 3 q c (2) + b δ, 2 ( t ) 2 (2 π ) 3 F (2) ( k − q , q ) F (2) ( k − q , q ) − � δ, 1 , s ( k − q , q ) s s × P 11 ( q ) P 11 ( | k − q | ) � � � d 3 q c (3) + b δ, 3 ( t )3 P 11 ( k ) δ, 3 , s ( k , − q , q ) P 11 ( q ) � (2 π ) 3 � d 3 q + b δ 2 ( t )2 (2 π ) 3 F (2) ( k − q , q ) P 11 ( q ) P 11 ( | k − q | ) s � k 2 � b c s ( t ) − 2(2 π ) c 2 s (1) ( t ) b δ, 1 ( t ) P 11 ( k ) + k 2 NL Biased Tracers in the EFT of LSS Effective field theory of biasing 10 / 18

  14. Error estimates and bias fits Error bars of the theory are given by the higher loop estimates: � � 3 k e.g. ∆ P hm ∼ (2 π ) b 1 P 11 ( k ) . k NL This determines the theory reach k max . k max [ h / Mpc ] bin0 bin1 Fits to N-body simulations: ��� _ �� � ��� = ���� � / ���� � ��� = ���� � / ��� mm 0 . 22 − 0 . 31 0 . 22 − 0 . 31 �� �� ��� ��� ��� χ � � hm + + - - - 0 . 24 − 0 . 35 0 . 22 − 0 . 35 ������ ����� + + + - - ����� ������ hh 0 . 19 − 0 . 32 0 . 17 − 0 . 30 + + - + - ����� ������ mmm 0 . 14 − 0 . 22 0 . 14 − 0 . 22 + + - - + ����� ������ + + + + - hmm 0 . 13 − 0 . 22 0 . 13 − 0 . 22 ����� ������ + + + - + ����� ������ hhm 0 . 13 − 0 . 22 0 . 13 − 0 . 22 + + - + + ���� ������� hhh + + + + + 0 . 13 − 0 . 21 0 . 13 − 0 . 21 ���� ������ Most of the constraint comes form the 3-pt function. Fits to 3-pt and 4-pt function would enable full predictivity for 2-pt function. Biased Tracers in the EFT of LSS Effective field theory of biasing 11 / 18

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend


More recommend