Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Improve the EH transfer function by updating the zd and sh_d fits #118

Open
wants to merge 5 commits into
base: master
Choose a base branch
from
Open

Improve the EH transfer function by updating the zd and sh_d fits #118

Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
158d7ac
Improve the fits for zd and sh_d from recent ML-GA fits in arXiv:2106…
MinhMPA Aug 28, 2023
20d830c
Commit the correct transfer.py file
MinhMPA Aug 28, 2023
f68b7bc
Final cleanup, add arXiv number
MinhMPA Aug 28, 2023
f5a9b1a
Fix identation
MinhMPA Aug 28, 2023
de331fe
Fix reference before assignment
MinhMPA Aug 28, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
59 changes: 38 additions & 21 deletions jax_cosmo/transfer.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,7 +7,7 @@
__all__ = ["Eisenstein_Hu"]


def Eisenstein_Hu(cosmo, k, type="eisenhu_osc"):
def Eisenstein_Hu(cosmo, k, type="eisenhu_sd"):
"""Computes the Eisenstein & Hu matter transfer function.

Parameters
Expand All @@ -19,8 +19,8 @@ def Eisenstein_Hu(cosmo, k, type="eisenhu_osc"):
Wave number in h Mpc^{-1}

type: str, optional
Type of transfer function. Either 'eisenhu' or 'eisenhu_osc'
(def: 'eisenhu_osc')
Type of transfer function. Either 'eisenhu', 'eisenhu_osc', 'eisenhu_zd', or 'eisenhu_sd'
(def: 'eisenhu_sd')

Returns
-------
Expand All @@ -30,11 +30,13 @@ def Eisenstein_Hu(cosmo, k, type="eisenhu_osc"):
Notes
-----
The Eisenstein & Hu transfer functions are computed using the fitting
formulae of :cite:`1998:EisensteinHu`
formulae of :cite:`1998:EisensteinHu`.
[OPTIONAL] Improving the redshift and sound horizon at drag epoch using fits from :cite:`Aizpuru:2021vhd`

"""
#############################################
# Quantities computed from 1998:EisensteinHu
# With the options to improve the redshift and sound horizon at drag epoch using fits from Aizpuru:2021vhd (arXiv:2106.00428)
# Provides : - k_eq : scale of the particle horizon at equality epoch
# - z_eq : redshift of equality epoch
# - R_eq : ratio of the baryon to photon momentum density
Expand All @@ -57,24 +59,39 @@ def Eisenstein_Hu(cosmo, k, type="eisenhu_osc"):
# z drag from Eq. (4)
b1 = 0.313 * np.power(w_m, -0.419) * (1.0 + 0.607 * np.power(w_m, 0.674))
b2 = 0.238 * np.power(w_m, 0.223)
z_d = (
1291.0
* np.power(w_m, 0.251)
/ (1.0 + 0.659 * np.power(w_m, 0.828))
* (1.0 + b1 * np.power(w_b, b2))
)

# Ratio of the baryon to photon momentum density at z_d Eq. (5)
if type in ('eisenhu', 'eisenhu_osc'):
# Fit for redshift of drag epoch in 1998:EisensteinHu
z_d = (
1291.0
* np.power(w_m, 0.251)
/ (1.0 + 0.659 * np.power(w_m, 0.828))
* (1.0 + b1 * np.power(w_b, b2))
)
else:
# Fit for redshift of drag epoch in Aizpuru:2021vhd
z_d = (1.0 + 428.169*np.power(w_b,0.256459)*np.power(w_m,0.616388) + 925.56*np.power(w_m,0.751615) ) / np.power(w_m,0.714129) # Eq (A2), Aizpuru:2021vhd
# Ratio of the baryon to photon momentum density at z_d Eq. (5), 1998:EisensteinHu
R_d = 31.5 * w_b / (T_2_7_sqr) ** 2 * (1.0e3 / z_d)
# Ratio of the baryon to photon momentum density at z_eq Eq. (5)
# Ratio of the baryon to photon momentum density at z_eq Eq. (5), 1998:EisensteinHu
R_eq = 31.5 * w_b / (T_2_7_sqr) ** 2 * (1.0e3 / z_eq)
# Sound horizon at drag epoch in h^-1 Mpc Eq. (6)
sh_d = (
2.0
/ (3.0 * k_eq)
* np.sqrt(6.0 / R_eq)
* np.log((np.sqrt(1.0 + R_d) + np.sqrt(R_eq + R_d)) / (1.0 + np.sqrt(R_eq)))
)
if type == 'einsenhu_sd':
aa1 = 0.00785436
aa2 = 0.17708400
aa3 = 0.00912388
aa4 = 0.61871100
aa5 = 11.9611000
aa6 = 2.81343000
aa7 = 0.78471900
# Fit for sound horizon at drag epoch in h^-1 Mpc, h*Eq (7), Aizpuru:2021vhd
sh_d = cosmo.h / (aa1*np.power(w_b,aa2) + aa3*np.power(w_m,aa4) + aa5*np.power(w_b,aa6)*np.power(w_m,aa7))
else:
# Sound horizon at drag epoch in h^-1 Mpc, Eq. (6), 1998:EisensteinHu
sh_d = (
2.0
/ (3.0 * k_eq)
* np.sqrt(6.0 / R_eq)
* np.log((np.sqrt(1.0 + R_d) + np.sqrt(R_eq + R_d)) / (1.0 + np.sqrt(R_eq)))
)
# Eq. (7) but in [hMpc^{-1}]
k_silk = (
1.6
Expand Down Expand Up @@ -104,7 +121,7 @@ def Eisenstein_Hu(cosmo, k, type="eisenhu_osc"):
C = 14.2 + 731.0 / (1.0 + 62.5 * q)
res = L / (L + C * q * q)

elif type == "eisenhu_osc":
elif type in ("eisenhu_osc", "eisenhu_zd", "eisenhu_sd"):
# Cold dark matter transfer function

# EH98 (11, 12)
Expand Down