BaryonEffectsEmulator

It is known that N-body simulation cannot trace the effects of baryons at medium and small cosmological scales. With this emulator we propose a fast and accurate remedy to this problem. For an accurate description of the BaryonEffectsEmulator refer to the research project MSc Thesis in the documentation folder.

Content

• Main source
  • BaryonEffectsEmulator.py: main source code of the emulator.
  • bee.pkl: data file on which the emulator is constructed.
• Documentation
  • MSc Thesis: research project with detailed documentation of the emulator.
• Example
  • example_code.py: example code for generation of the boost and graphical representation.

Installation

• Prerequisites: pandas, scipy, numpy.
• The installation process is straightforward, one has simply to download the ZIP file. Consequntely one has to import the functions located in the file BaryonEffecsEmulator.py into its own python code.

Usage

This section explains precedure to follow in order to get the boost P_BCM/P_DMO. After the download of the files one can create a new python code and proceed as follow:

from BaryonEffectsEmulator import *

If the python file BaryonEffectsEmulator.py is located in a different folder, then first change the path for example with

import sys
sys.path.insert(0, '/path/to/BaryonEffectsEmulator')

Once this is done one has to define a baryonic correction model, the redshifts, and the wavenumbers at which the boost has to be calculated, e.g.

MyBCM = {'f_b': 0.14, 'logMc': 14, 'mu': 0.4, 'theta_ej':4.0, 'eta_tot': 0.3, 'eta_cga': 0.6}
z=[0.3,0.9,1.5]
k=np.logspace(-1,1,1000)

The k-vector is an optional parameter. If it is not given the power suppression will be evaluated at the standard k-values related to the emulator construction. On the other hand, a linear extrapolation is performed for k-values outside of the standard range.

As last step one should simply call the function get_boost and access the results as follows:

result=get_boost(z,MyBCM,keval)
k=result['k']
boost0=result['z0']
boost1=result['z1']
boost2=result['z2']