This program is a part of Master research advised by Prof. Marilena Loverde at Stony Brook University. The goal of this program is constraining cosmological parameters by Fisher analysis using the cross-correlation functions of Integrated Sachs-Wolfe effect and 21cm brightness temperature fluctuations at dark ages. A paper containing results of this program is in preparation.

• This program is written with python 2.7.
• default in /source/path.py should be changed to be a path of 'ISW_21cm' folder in the machine.
• Should do 'make' in both 'class_syn' and 'class_new' folders.

• class_syn
  • CLASS in syncronouse gauge.
• class_new
  • CLASS in newtonian gauge.
• data
  • This is a folder to save data from CLASS such as transfer functions, CMB power spectrums, and free electron fraction.
• params_Yp
  • Sets of cosmological parameters for Fisher analysis. Yp is also one of parameters.
• params_Yp_BBN
  • Sets of cosmological parameters for Fisher analysis. Yp is fixed by BBN constraint. See Eq. (70) in Planck 2015 results. XIII.
• result
  • In this folder, the fisher matrix and the constraints from Fisher analysis are saved.
• result_Yp
  • The auto- and cross-correlation of 21cm fluctuations and ISW effect are saved using parameters in params_Yp.
• result_Yp_BBN
  • The auto- and cross-correlation of 21cm fluctuations and ISW effect are saved using parameters in params_Yp_BBN.
• source
  • Contains main source files.

• source/

  • path.py: this defines paths of every folder.

  • selection_function21cm.py: this defines selection functions for the obversed frequency of 21 cm fluctuations.

  • run.py: this runs CLASS code to get transfer functions, CMB power spectrums, and free electron fraction. It has two functions each of which is for Fisher analysis with CMB or 21cm.

  • cl_21.py: this calculates auto- and cross-correlation functions of 21cm using data from CLASS.

  • fisher.py: this does Fisher analysis for CMB and 21cm.

  • fisher_which.py: this determines which Fisher analysis will be done (CMB or 21cm) and which conditions for Yp (BBN constraint or not) will be considered.

  • tools.py: this contains functions to interpolate recombination coefficient from table given in HyRec code. Its original file is hydrogen.c of HyRec code.

  • updateparams.py: this updates CLASS ini file (params_prac_.ini) using parameters in params_Yp and params_Yp_BBN.

• run_fisher.py: choose between CMB and 21cm and also condition for Yp. Results (fisher matrix and constraints of cosmological parameters) will be saved in result folder.