Before Running

Decide on a “data directory”

Create a new directory where you would like to store the fits files which we will reduce and analyze. In the next part of this Quickstart, you will download these fits files and move them into this directory.

Decide on a “run directory”

Before we can run PACMAN we need to create a run directory.

All runs will be saved in a run directory. For the analysis of the GJ1214 data, I have the following directory setup:

└── Desktop
        └── Projects
                └── Observations
                        └── Hubble
                                └── GJ1214_13021 (="run directory")
                                        ├── fit_par.txt
                                        └── obs_par.pcf
        └── Data
                └── GJ1214_Hubble13021 (="data directory")
                    ├── ibxy06d0q_ima.fits
                    ├── ...
                    └── ibxy07ryq_ima.fits

In this case, /user/Desktop/Projects/Observations/Hubble/GJ1214_13021 is my run directory.

Copy run_files contents into your run directory

The source code of PACMAN contains a directory called “run_files”. In there are three different files:


  • fit_par.txt

  • obs_par.pcf

These three files are part of the package but can also be downloaded under this link: Download here.

This files have to be copied over to the run directory. You should then have the following:

GJ1214_13021 (="run directory")
├── fit_par.txt
└── obs_par.pcf

Set up the pcf

The pacman control file, or pcf page, stores all the parameters the user can tune for a particular run. Before we start, paths to the data and the run directory (data_dir and run_dir) have to be set in the pcf.

Navigate to the run directory, open the pcf and modify the entries data_dir and run_dir with the absolute paths to the data directory and run directory, respectively. E.g.,

rundir   /home/zieba/Desktop/Projects/Observations/Hubble/GJ1214_13021
datadir   /home/zieba/Desktop/Data/GJ1214_Hubble13021

In the next step of the quickstart, we will download the data (fits files) needed for our analysis using the python package astroquery.